3008fc Low Dropout Linear Regulators
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Transcript of 3008fc Low Dropout Linear Regulators
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LT3008 Series
1
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TEMPERATURE (C)
D R O P O U T V O L T A G E ( m
V ) Q
U I E S
C E N T
C U R R E N T
( A
)
400
3008 TA01b
200
100
50
0
500
300
250
150
5
350
2
3
1
0
6
450
4
50 25 0 25 50 75 100 125 150
ILOAD = 20mADROPOUTVOLTAGE
IQ
TYPICAL APPLICATION
FEATURES
APPLICATIONS
DESCRIPTION
3 A IQ , 20mA, 45VLow Dropout Linear Regulators
The LT3008 series are micropower, low dropout voltag(LDO) linear regulators. The devices supply 20mA outpcurrent with a dropout voltage of 300mV. No-load quiescecurrent is 3A. Ground pin current remains at less tha5% of output current as load increases. In shutdownquiescent current is less than 1A.
The LT3008 regulators optimize stability and transieresponse with low ESR ceramic capacitors, requiring minimum of only 2.2F. The regulators do not requir
the addition of ESR as is common with other regulatorInternal protection circuitry includes current limitinthermal limiting, reverse-battery protection and reversecurrent protection.
The LT3008 series are ideal for applications that requimoderate output drive capability coupled with ultralostandby power consumption. The device is available xed output voltages of 1.2V, 1.5V, 1.8V, 2.5V, 3.3V an5V, and an adjustable version with an output voltage rangof 0.6V to 44.5V. The LT3008 is available in the thermaenhanced 6-lead DFN and 8-lead TSOT-23 packages.
3.3V, 20mA Supply with Shutdown
n Ultralow Quiescent Current: 3An Input Voltage Range: 2.0V to 45Vn Output Current: 20mAn Dropout Voltage: 300mVn Adjustable Output (VADJ = VOUT(MIN) = 600mV)n Fixed Output Voltages: 1.2V, 1.5V, 1.8V, 2.5V, 3.3V, 5Vn Output Tolerance: 2% Over Load, Line and
Temperaturen Stable with Low ESR, Ceramic Output Capacitors
(2.2F Minimum)n Shutdown Current:
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LT3008 Series
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PIN CONFIGURATION
ABSOLUTE MAXIMUM RATINGS
IN Pin Voltage ......................................................... 50VOUT Pin Voltage ...................................................... 50VInput-to-Output Differential Voltage ........................ 50VADJ Pin Voltage ...................................................... 50VSENSE Pin Voltage .................................................. 50VSHDN Pin Voltage (Note 8) ..................................... 50VOutput Short-Circuit Duration .......................... Indenite
(Note 1)
TOP VIEW
GND
SHDN
IN
**SENSE/ADJ
OUT
OUT
DC PACKAGE6-LEAD (2mm 2mm) PLASTIC DFN
4
57
6
3
2
1
TJMAX = 125C, JA = 65C/W TO 85C/W*EXPOSED PAD (PIN 7) IS GND, MUST BE SOLDERED TO PCB
SHDN 1
GND 2
GND 3
GND 4
8 NC
7 ADJ/SENSE**
6 OUT
5 IN
TOP VIEW
TS8 PACKAGE8-LEAD PLASTIC TSOT-23
TJMAX = 125C, JA = 65C/W TO 85C/W*
Operating Junction Temperature Range (Notes 2, 3) E, I Grade ...........................................40C to 125 MP Grade ...........................................55C to 125Storage Temperature Range ...................65C to 150CLead Temperature: Soldering, 10 sec TS8 Package Only ............................................. 300
ORDER INFORMATION
LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERAT
LT3008EDC#PBF LT3008EDC#TRPBF LDPS 6-Lead (2mm 2mm) Plastic DFN 40C to 125C
LT3008IDC#PBF LT3008IDC#TRPBF LDPS 6-Lead (2mm 2mm) Plastic DFN 40C to 125C
LT3008EDC-1.2#PBF LT3008EDC-1.2#TRPBF LFHC 6-Lead (2mm 2mm) Plastic DFN 40C to 125C
LT3008IDC-1.2#PBF LT3008IDC-1.2#TRPBF LFHC 6-Lead (2mm 2mm) Plastic DFN 40C to 125C
LT3008EDC-1.5#PBF LT3008EDC-1.5#TRPBF LFHF 6-Lead (2mm 2mm) Plastic DFN 40C to 125C
LT3008IDC-1.5#PBF LT3008IDC-1.5#TRPBF LFHF 6-Lead (2mm 2mm) Plastic DFN 40C to 125C
LT3008EDC-1.8#PBF LT3008EDC-1.8#TRPBF LFHH 6-Lead (2mm 2mm) Plastic DFN 40C to 125C
LT3008IDC-1.8#PBF LT3008IDC-1.8#TRPBF LFHH 6-Lead (2mm 2mm) Plastic DFN 40C to 125C
LT3008EDC-2.5#PBF LT3008EDC-2.5#TRPBF LFHK 6-Lead (2mm 2mm) Plastic DFN 40C to 125C
LT3008IDC-2.5#PBF LT3008IDC-2.5#TRPBF LFHK 6-Lead (2mm 2mm) Plastic DFN 40C to 125C
LT3008EDC-3.3#PBF LT3008EDC-3.3#TRPBF LFHN 6-Lead (2mm 2mm) Plastic DFN 40C to 125C
LT3008IDC-3.3#PBF LT3008IDC-3.3#TRPBF LFHN 6-Lead (2mm 2mm) Plastic DFN 40C to 125C
LT3008EDC-5#PBF LT3008EDC-5#TRPBF LFHQ 6-Lead (2mm 2mm) Plastic DFN 40C to 125C
LT3008IDC-5#PBF LT3008IDC-5#TRPBF LFHQ 6-Lead (2mm 2mm) Plastic DFN 40C to 125C
LT3008ETS8#PBF LT3008ETS8#TRPBF LTDSX 8-Lead Plastic TSOT-23 40C to 125C
* See the Applications Information Section.** SENSE for Fixed Voltage Output Versions.
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LT3008 Series
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ORDER INFORMATION
LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERAT
LT3008ITS8#PBF LT3008ITS8#TRPBF LTDSX 8-Lead Plastic TSOT-23 40C to 125C
LT3008MPTS8#PBF LT3008MPTS8#TRPBF LTDSX 8-Lead Plastic TSOT-23 55C to 125C
LT3008ETS8-1.2#PBF LT3008ETS8-1.2#TRPBF LTFHD 8-Lead Plastic TSOT-23 40C to 125C
LT3008ITS8-1.2#PBF LT3008ITS8-1.2#TRPBF LTFHD 8-Lead Plastic TSOT-23 40C to 125C
LT3008MPTS8-1.2#PBF LT3008MPTS8-1.2#TRPBF LTFHD 8-Lead Plastic TSOT-23 55C to 125C
LT3008ETS8-1.5#PBF LT3008ETS8-1.5#TRPBF LTFHG 8-Lead Plastic TSOT-23 40C to 125C
LT3008ITS8-1.5#PBF LT3008ITS8-1.5#TRPBF LTFHG 8-Lead Plastic TSOT-23 40C to 125C
LT3008MPTS8-1.5#PBF LT3008MPTS8-1.5#TRPBF LTFHG 8-Lead Plastic TSOT-23 55C to 125C
LT3008ETS8-1.8#PBF LT3008ETS8-1.8#TRPBF LTFHJ 8-Lead Plastic TSOT-23 40C to 125C
LT3008ITS8-1.8#PBF LT3008ITS8-1.8#TRPBF LTFHJ 8-Lead Plastic TSOT-23 40C to 125C
LT3008MPTS8-1.8#PBF LT3008MPTS8-1.8#TRPBF LTFHJ 8-Lead Plastic TSOT-23 55C to 125C
LT3008ETS8-2.5#PBF LT3008ETS8-2.5#TRPBF LTFHM 8-Lead Plastic TSOT-23 40C to 125C
LT3008ITS8-2.5#PBF LT3008ITS8-2.5#TRPBF LTFHM 8-Lead Plastic TSOT-23 40C to 125CLT3008MPTS8-2.5#PBF LT3008MPTS8-2.5#TRPBF LTFHM 8-Lead Plastic TSOT-23 55C to 125C
LT3008ETS8-3.3#PBF LT3008ETS8-3.3#TRPBF LTFHP 8-Lead Plastic TSOT-23 40C to 125C
LT3008ITS8-3.3#PBF LT3008ITS8-3.3#TRPBF LTFHP 8-Lead Plastic TSOT-23 40C to 125C
LT3008MPTS8-3.3#PBF LT3008MPTS8-3.3#TRPBF LTFHP 8-Lead Plastic TSOT-23 55C to 125C
LT3008ETS8-5#PBF LT3008ETS8-5#TRPBF LTFHR 8-Lead Plastic TSOT-23 40C to 125C
LT3008ITS8-5#PBF LT3008ITS8-5#TRPBF LTFHR 8-Lead Plastic TSOT-23 40C to 125C
LT3008MPTS8-5#PBF LT3008MPTS8-5#TRPBF LTFHR 8-Lead Plastic TSOT-23 55C to 125C
LEAD BASED FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERAT
LT3008EDC LT3008EDC#TR LDPS 6-Lead (2mm 2mm) Plastic DFN 40C to 125C
LT3008IDC LT3008IDC#TR LDPS 6-Lead (2mm 2mm) Plastic DFN 40C to 125C
LT3008EDC-1.2 LT3008EDC-1.2#TR LFHC 6-Lead (2mm 2mm) Plastic DFN 40C to 125C
LT3008IDC-1.2 LT3008IDC-1.2#TR LFHC 6-Lead (2mm 2mm) Plastic DFN 40C to 125C
LT3008EDC-1.5 LT3008EDC-1.5#TR LFHF 6-Lead (2mm 2mm) Plastic DFN 40C to 125C
LT3008IDC-1.5 LT3008IDC-1.5#TR LFHF 6-Lead (2mm 2mm) Plastic DFN 40C to 125C
LT3008EDC-1.8 LT3008EDC-1.8#TR LFHH 6-Lead (2mm 2mm) Plastic DFN 40C to 125C
LT3008IDC-1.8 LT3008IDC-1.8#TR LFHH 6-Lead (2mm 2mm) Plastic DFN 40C to 125C
LT3008EDC-2.5 LT3008EDC-2.5#TR LFHK 6-Lead (2mm 2mm) Plastic DFN 40C to 125C
LT3008IDC-2.5 LT3008IDC-2.5#TR LFHK 6-Lead (2mm 2mm) Plastic DFN 40C to 125C
LT3008EDC-3.3 LT3008EDC-3.3#TR LFHN 6-Lead (2mm 2mm) Plastic DFN 40C to 125C
LT3008IDC-3.3 LT3008IDC-3.3#TR LFHN 6-Lead (2mm 2mm) Plastic DFN 40C to 125C
LT3008EDC-5 LT3008EDC-5#TR LFHQ 6-Lead (2mm 2mm) Plastic DFN 40C to 125CLT3008IDC-5 LT3008IDC-5#TR LFHQ 6-Lead (2mm 2mm) Plastic DFN 40C to 125C
LT3008ETS8 LT3008ETS8#TR LTDSX 8-Lead Plastic TSOT-23 40C to 125C
LT3008ITS8 LT3008ITS8#TR LTDSX 8-Lead Plastic TSOT-23 40C to 125C
LT3008MPTS8 LT3008MPTS8#TR LTDSX 8-Lead Plastic TSOT-23 55C to 125C
LT3008ETS8-1.2 LT3008ETS8-1.2#TR LTFHD 8-Lead Plastic TSOT-23 40C to 125C
LT3008ITS8-1.2 LT3008ITS8-1.2#TR LTFHD 8-Lead Plastic TSOT-23 40C to 125C
LT3008MPTS8-1.2 LT3008MPTS8-1.2#TR LTFHD 8-Lead Plastic TSOT-23 55C to 125C
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LT3008 Series
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ELECTRICAL CHARACTERISTICS The l denotes the specications which apply over the full operatingtemperature range, otherwise specications are at TJ = 25C. (Note 2)
PARAMETER CONDITIONS MIN TYP MAXOperating Voltage l 2 45 V
Regulated Output Voltage LT3008-1.2: VIN = 2V, ILOAD = 100A2V < VIN < 45V, 1A < ILOAD < 20mA l
1.1881.176
1.21.2
1.2121.224
VV
LT3008-1.5: VIN = 2.05V, ILOAD = 100A2.05V < VIN < 45V, 1A < ILOAD < 20mA l
1.4851.47
1.51.5
1.5151.53
VV
LT3008-1.8: VIN = 2.35V, ILOAD = 100A2.35V < VIN < 45V, 1A < ILOAD < 20mA l
1.7821.764
1.81.8
1.8181.836
VV
LT3008-2.5: VIN = 3.05V, ILOAD = 100A3.05V < VIN < 45V, 1A < ILOAD < 20mA l
2.4752.45
2.52.5
2.5252.55
VV
LT3008-3.3: VIN = 3.85V, ILOAD = 100A3.85V < VIN < 45V, 1A < ILOAD < 20mA l
3.2673.234
3.33.3
3.3333.366
VV
LT3008-5: VIN = 5.55V, ILOAD = 100A5.55V < VIN < 45V, 1A < ILOAD < 20mA l
4.954.9
55
5.055.1
VV
ADJ Pin Voltage (Notes 3, 4) VIN = 2V, ILOAD = 100A2V < VIN < 45V, 1A < ILOAD < 20mA l
594588
600600
606612
mVmV
Line Regulation (Note 3) LT3008-1.2: VIN = 2V to 45V, ILOAD = 1mALT3008-1.5: VIN = 2.05V to 45V, ILOAD = 1mALT3008-1.8: VIN = 2.35V to 45V, ILOAD = 1mALT3008-2.5: VIN = 3.05V to 45V, ILOAD = 1mALT3008-3.3: VIN = 3.85V to 45V, ILOAD = 1mALT3008-5: VIN = 5.55V to 45V, ILOAD = 1mALT3008: VIN = 2V to 45V, ILOAD = 1mA
l
l
l
l
l
l
l
1.21.51.82.53.35
0.6
67.59
12.516.5253
mVmVmVmVmVmVmV
LEAD BASED FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERAT
LT3008ETS8-1.5 LT3008ETS8-1.5#TR LTFHG 8-Lead Plastic TSOT-23 40C to 125C
LT3008ITS8-1.5 LT3008ITS8-1.5#TR LTFHG 8-Lead Plastic TSOT-23 40C to 125C
LT3008MPTS8-1.5 LT3008MPTS8-1.5#TR LTFHG 8-Lead Plastic TSOT-23 55C to 125C
LT3008ETS8-1.8 LT3008ETS8-1.8#TR LTFHJ 8-Lead Plastic TSOT-23 40C to 125C
LT3008ITS8-1.8 LT3008ITS8-1.8#TR LTFHJ 8-Lead Plastic TSOT-23 40C to 125C
LT3008MPTS8-1.8 LT3008MPTS8-1.8#TR LTFHJ 8-Lead Plastic TSOT-23 55C to 125C
LT3008ETS8-2.5 LT3008ETS8-2.5#TR LTFHM 8-Lead Plastic TSOT-23 40C to 125C
LT3008ITS8-2.5 LT3008ITS8-2.5#TR LTFHM 8-Lead Plastic TSOT-23 40C to 125C
LT3008MPTS8-2.5 LT3008MPTS8-2.5#TR LTFHM 8-Lead Plastic TSOT-23 55C to 125C
LT3008ETS8-3.3 LT3008ETS8-3.3#TR LTFHP 8-Lead Plastic TSOT-23 40C to 125C
LT3008ITS8-3.3 LT3008ITS8-3.3#TR LTFHP 8-Lead Plastic TSOT-23 40C to 125C
LT3008MPTS8-3.3 LT3008MPTS8-3.3#TR LTFHP 8-Lead Plastic TSOT-23 55C to 125C
LT3008ETS8-5 LT3008ETS8-5#TR LTFHR 8-Lead Plastic TSOT-23 40C to 125CLT3008ITS8-5 LT3008ITS8-5#TR LTFHR 8-Lead Plastic TSOT-23 40C to 125C
LT3008MPTS8-5 LT3008MPTS8-5#TR LTFHR 8-Lead Plastic TSOT-23 55C to 125C
Consult LTC Marketing for parts specied with wider operating temperature ranges. *The temperature grade is identied by a label on the shipping con
For more information on lead free part marking, go to:http://www.linear.com/leadfree/ For more information on tape and reel specications, go to:http://www.linear.com/tapeandreel/
ORDER INFORMATION
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LT3008 Series
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PARAMETER CONDITIONS MIN TYP MAX
Load Regulation (Note 3) LT3008-1.2: VIN = 2V, ILOAD = 1A to 10mA V
IN = 2V, I
LOAD = 1A to 20mA
l
l0.81
410
mVmV
LT3008-1.5: VIN = 2.05V, ILOAD = 1A to 10mA VIN = 2.05V, ILOAD = 1A to 20mA
l
l1
1.3513
mVmV
LT3008-1.8: VIN = 2.35V, ILOAD = 1A to 10mA VIN = 2.35V, ILOAD = 1A to 20mA
l
l1.21.5
615
mVmV
LT3008-2.5: VIN = 3.05V, ILOAD = 1A to 10mA VIN = 3.05V, ILOAD = 1A to 20mA
l
l1.72.1
8.321
mVmV
LT3008-3.3: VIN = 3.85V, ILOAD = 1A to 10mA VIN = 3.85V, ILOAD = 1A to 20mA
l
l2.22.8
1128
mVmV
LT3008-5: VIN = 5.55V, ILOAD = 1A to 10mA VIN = 5.55V, ILOAD = 1A to 20mA
l
l3.44.2
1742
mVmV
LT3008: VIN = 2V, ILOAD = 1A to 10mA VIN = 2V, ILOAD = 1A to 20mA
l
l0.40.5
25
mVmV
Dropout VoltageVIN = VOUT(NOMINAL) (Notes 5, 6)
ILOAD = 100AILOAD = 100A l
115 180250
mVmV
ILOAD = 1mAILOAD = 1mA l
170 250350
mVmV
ILOAD = 10mAILOAD = 10mA l
270 340470
mVmV
ILOAD = 20mAILOAD = 20mA l
300 365500
mVmV
Quiescent Current (Notes 6, 7) ILOAD = 0AILOAD = 0A l
36
AA
GND Pin CurrentVIN = VOUT(NOMINAL) + 0.5V (Notes 6, 7)
ILOAD = 0AILOAD = 100AILOAD = 1mAILOAD = 10mAILOAD = 20mA
l
l
l
l
l
3621160350
612505001200
AAAAA
Output Voltage Noise (Note 9) COUT = 2.2F, ILOAD = 20mA, BW = 10Hz to 100kHz 92 VRMSADJ Pin Bias Current 10 0.4 10 nA
Shutdown Threshold VOUT = Off to OnVOUT = On to Off
l
l 0.250.670.61
1.5 VV
SHDN Pin Current VSHDN = 0V, VIN = 45VVSHDN = 45V, VIN = 45V
l
l 0.65 12
AA
Quiescent Current in Shutdown VIN = 6V, VSHDN = 0V l
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LT3008 Series
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Note 1: Stresses beyond those listed under Absolute Maximum Ratingsmay cause permanent damage to the device. Exposure to any AbsoluteMaximum Rating condition for extended periods may affect devicereliability and lifetime.Note 2: The LT3008 regulators are tested and specied under pulseload conditions such that TJ TA. The LT3008E is guaranteed to meetperformance specications from 0C to 125C operating junctiontemperature. Specications over the 40C to 125C operating junctiontemperature range are assured by design, characterization and correlationwith statistical process controls. The LT3008I is guaranteed over the full40C to 125C operating junction temperature range. The LT3008MP is100% tested and guaranteed over the 55C to 125C operating junctiontemperature range.Note 3: The LT3008 adjustable version is tested and specied for theseconditions with the ADJ pin connected to the OUT pin.Note 4: Operating conditions are limited by maximum junctiontemperature. The regulated output voltage specication will not applyfor all possible combinations of input voltage and output current. Whenoperating at the maximum input voltage, the output current range must belimited. When operating at the maximum output current, the input voltagemust be limited.
Note 5: Dropout voltage is the minimum input to output voltage differentneeded to maintain regulation at a specied output current. In dropout, thoutput voltage equals (VIN VDROPOUT). For the LT3008-1.2 and LT3008-1.5, dropout voltage will be limited by the minimum input voltage.Note 6: To satisfy minimum input voltage requirements, the LT3008adjustable version is tested and specied for these conditions with anexternal resistor divider (61.9k bottom, 280k top) which sets VOUT to 3.3V.The external resistor divider adds 9.69A of DC load on the output. Thisexternal current is not factored into GND pin current.Note 7: GND pin current is tested with VIN = VOUT(NOMINAL) + 0.55V anda current source load. GND pin current will increase in dropout. For thexed output voltage versions, an internal resistor divider will add about1A to the GND pin current. See the GND Pin Current curves in the TypiPerformance Characteristics section.Note 8: TheSHDN pin can be driven below GND only when tied to the INpin directly or through a pull-up resistor. If theSHDNpin is driven belowGND by more than 0.3V while IN is powered, the output will turn on.Note 9: Output noise is listed for the adjustable version with the ADJ pinconnected to the OUT pin. See the RMS Output Noise vs Load Currentcurve in the Typical Performance Characteristics Section.
ELECTRICAL CHARACTERISTICS The l denotes the specications which apply over the full operatingtemperature range, otherwise specications are at TJ = 25C. (Note 2)
PARAMETER CONDITIONS MIN TYP MAX
Current Limit VIN = 45V, VOUT = 0V
IN = V
OUT(NOMINAL) + 1V, V
OUT = 5% l 22
75 mAmA
Input Reverse-Leakage Current VIN = 45V, VOUT = 0 l 1 30 A
Reverse-Output Current VOUT = 1.2V, VIN = 0 0.6 10 A
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0
0.6
0.4
0.2
0.8
1
1.2
1.4
1.6
1.8
2
TEMPERATURE (C)
M I N I M U M I N P U T V O L T A G E ( V )
3008 G03
ILOAD = 20mA
50 25 0 25 50 75 100 125 150
OUTPUT CURRENT (mA)0
0
D R O P O U T V O L T A G E ( m V )
50
150
200
250
10 12 14 20
450
100
2 4 6 8 16 18
300
350
400
3008 G01
TJ = 125C
TJ = 25C
TEMPERATURE (C)
0
D R O P O U T V O L T A G E ( m V )
50
150
200
250
450
100
300
350
400
3008 G02
20mA10mA
1mA100A
50 25 0 25 50 75 100 125 150
Dropout Voltage Dropout Voltage Minimum Input Voltage
TYPICAL PERFORMANCE CHARACTERISTICS TA = 25C, unless otherwise noted.
Output VoltageLT3008-1.8
TEMPERATURE (C)
O U T P U T V O L T A G E ( V )
3008 G07
1.788
1.8241.8301.836
1.7701.776
1.812
1.800
1.782
1.816
1.764
1.806
1.794
50 25 0 25 50 75 100 125 150
ILOAD = 100A
Output VoltageLT3008-3.3
TEMPERATURE (C)
O U T P U T V O L T A G E ( V )
3008 G08
2.480
2.540
2.550
2.460
2.520
2.500
2.470
2.530
2.450
2.510
2.490
50 25 0 25 50 75 100 125 150
ILOAD = 100A
Output VoltageLT3008-2.5
TEMPERATURE (C)
O U T P U T V O L T A G E ( V )
3008 G09
3.267
3.278
3.355
3.366
3.245
3.322
3.300
3.256
3.333
3.344
3.234
3.311
3.289
50 25 0 25 50 75 100 125 150
ILOAD = 100A
ADJ Pin Voltage
TEMPERATURE (C)
A D J P I N V O L T A G E ( V )
3008 G04
0.596
0.6080.6100.612
0.5900.592
0.604
0.600
0.594
0.606
0.588
0.602
0.598
50 25 0 25 50 75 100 125 150
IL = 100A
Output VoltageLT3008-1.2
Output VoltageLT3008-1.5
TEMPERATURE (C)
O U T P U T V O L T A G E ( V )
3008 G05
1.192
1.2161.2201.224
1.1801.184
1.208
1.200
1.188
1.212
1.176
1.204
1.196
50 25 0 25 50 75 100 125 150
ILOAD = 100A
TEMPERATURE (C)
O U T P U T V O L T A G E ( V )
3008 G06
1.490
1.5201.5251.530
1.4751.480
1.510
1.500
1.485
1.515
1.470
1.505
1.495
50 25 0 25 50 75 100 125 150
ILOAD = 100A
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TYPICAL PERFORMANCE CHARACTERISTICS TA = 25C, unless otherwise noted.
0
200
450
500
2 4 6
100
350
150
400
50
0
300
250
1 3 8 105 7 9
3008 G15INPUT VOLTAGE (V)
G N D P I N C U R R E N T ( A )
RL = 75, IL = 20mA
RL = 150, IL = 10mA
RL = 1.5k, IL = 1mA
RL = 15k, IL = 100A
0
200
450
500
2 4 6
100
350
150
400
50
0
300
250
1 3 8 105 7 9
3008 G14INPUT VOLTAGE (V)
G N D P I N C U R R E N T ( A )
RL = 60, IL = 20mA
RL = 120, IL = 10mA
RL = 1.2k, IL = 1mA
RL = 12k, IL = 100A
GND Pin CurrentLT3008-1.2
GND Pin CurrentLT3008-1.5
GND Pin CurrentLT3008-1.8
0
200
450
500
2 4 6
100
350
150
400
50
0
300250
1 3 8 105 7 9
3008 G16INPUT VOLTAGE (V)
G N D P I N C U R R E N
T ( A )
RL = 90, IL = 20mA
RL = 180, IL = 10mA
RL = 1.8k, IL = 1mA
RL = 18k, IL = 100A
GND Pin CurrentLT3008-2.5
GND Pin CurrentLT3008-3.3
0
200
450
500
2 4 6
100
350
150
400
50
0
300250
1 3 8 105 7 9
3008 G17INPUT VOLTAGE (V)
G N D P I N C U R R E N
T ( A )
RL = 125, IL = 20mA
RL = 250, IL = 10mA
RL = 2.5k, IL = 1mA
RL = 25k, IL = 100A
0
200
450
500
2 4 6
100
350
150
400
50
0
300250
1 3 8 105 7 9
3008 G18INPUT VOLTAGE (V)
G N D P I N C U R R E N
T ( A )
RL = 165, IL = 20mA
RL = 330, IL = 10mA
RL = 3.3k, IL = 1mA
RL = 33k, IL = 100A
Quiescent Current
INPUT VOLTAGE (V)
Q
U I E S C E N T C U R R E N T ( A )
3008 G13
12
30
36
18
21
9
0
27
24
15
0 21 43 5 6 87 9 10
LT3008-1.2LT3008-1.5LT3008-1.8LT3008-2.5LT3008-3.3LT3008-5
TEMPERATURE (C)
O U T P U T V O L T A G E ( V )
3008 G10
4.950
5.075
5.100
5.025
5.000
4.925
5.050
4.900
4.975
50 25 0 25 50 75 100 125 150
ILOAD = 100A
Output VoltageLT3008-5 ADJ Pin Bias Current Adjustable Quiescent Current
TEMPERATURE (C)
A D J P I N B I A S C U R R E N T ( n A )
3008 G05
4
8
10
10
8
4
0
6
6
2
2
50 25 0 25 50 75 100 125 150TEMPERATURE (C)
Q U I E S C E N T C U R R E N T ( A )
3008 G06
2
5
6
1
4
3
050 25 0 25 50 75 100 125 150
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3008fc
TYPICAL PERFORMANCE CHARACTERISTICS TA = 25C, unless otherwise noted.
SHDN Pin Input Current SHDN Pin Input Current
0
0.8
1.8
2
10 20 30
0.4
1.4
0.6
1.6
0.2
0
1.2
1
5 15 4525 35 40
3008 G22
SHDN PIN VOLTAGE (V)
S H D N P I N I N P U T C U R R E N T ( A )
50
0.8
2
0 25 75
0.4
1.6
0.6
1.8
0.2
0
1.4
1
1.2
25 100 15050 125
3008 G23
TEMPERATURE (C)
S H D N P I N I N P U T C U R R E N T ( A )
VSHDN = 45V
Current Limit
Reverse-Output Current
40
100
20
70
80
30
90
10
0
60
50
3008 G24
TEMPERATURE (C)
C U R R E N T L I M I T ( m A )
50 0 7525 25 15050 100 125
VIN = 2V
VIN = 45V
3008 G25
TEMPERATURE (C)
R E V E R S E O U T P U T C U R R E N T ( A )
20
50
10
35
40
15
45
5
0
3025
50 0 7525 25 15050 100 125
OUT
ADJ
OUT = ADJ = 1.2VIN =SHDN = GND
Input Ripple Rejection
0
10
30
20
40
50
70
60
90
80
FREQUENCY (Hz)3008 G26
10 100 1000 10000010000 1000000
I N P U T R I P P L E R E J E C T I O N ( d B )
VIN = 2.1V + 50mVRMSVOUT = 600mVILOAD= 20mA
2.2F
10F
Input Ripple Rejection
I N P U T R I P P L E R E J E C T I O N ( d B )
60
80
30
40
50
70
20
10
0
3008 G27
TEMPERATURE (C)50 0 7525 25 15050 100 125
VIN = VOUT(NOMINAL) + 2V + 0.5VP-P RIPPLE AT f = 120HzILOAD= 20mA
GND Pin CurrentLT3008-5
0
200
450
500
2 4 6
100
350
150
400
50
0
300
250
1 3 8 105 7 9
3008 G19INPUT VOLTAGE (V)
G N D P I N C U R R E N T ( A ) RL = 250, IL = 20mA
RL = 500, IL = 10mA
RL = 5k, IL = 1mA
RL = 50k, IL = 100A
GND Pin Current vs ILOAD
1
10
100
1000
LOAD (mA)
G N D C U R R E N T ( A )
3008 G20
0.001 0.01 0.1 1 10 100
VIN = 3.8VVOUT = 3.3V
50
0.6
1.41.5
0 75
0.3
1.21.1
0.40.5
1.3
0.10.2
0
10.90.80.7
25 25 15050 100 125
3008 G21
TEMPERATURE (C)
S H D N P I N T H R E S H O L D ( V )
OFF TO ON
ON TO OFF
SHDN Pin Thresholds
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TYPICAL PERFORMANCE CHARACTERISTICS TA = 25C, unless otherwise noted.
Transient Response
500s/DIV
VOUT50mV/DIV
IOUT20mA/DIV
3008 G31
IOUT= 1mA TO 20mAVIN= 5.5VVOUT= 5VCOUT= 2.2F
Transient Response
500s/DIV
VOUT50mV/DIV
IOUT20mA/DIV
3008 G32
IOUT= 1mA TO 20mAVIN= 5.5VVOUT= 5VCOUT= 10F
Transient Response (Load Dump)
1ms/DIV
VOUT50mV/DIV
45V
12VVIN
10V/DIV
3008 G33
VOUT= 5VIOUT= 20mACOUT= 4.7F
Load Regulation Output Noise Spectral Density
FREQUENCY (Hz)
0.1 O U T P U T N O I S E S P E C T R A L D E N S I T Y ( V H z )
1
100
10
3008 G29
10 100 1k 10k 100k
5V3.3V2.5V1.8V1.5V1V0.6V
COUT = 2.2FILOAD = 20mA
0
0.5
2
2.5
1.5
1
3
3.5
4
4.5
5
L O A D R E G U L A T I O N ( m V )
3008 G28
TEMPERATURE (C)50 0 7525 25 15050 100 125
IL = 1A to 20mAVOUT = 600mVVIN = 2V
RMS Output Noisevs Load Current
ILOAD (mA)0.001
350
450
400
500
10
3008 G30
300
250
0.01 0.1 1 100
200
100
150
50
0
O U T P U T N O I S E ( V
R M S
)
3.3V
2.5V
1.8V
1.2V
0.6V
1.5V
5VCOUT = 10F
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PIN FUNCTIONS
SHDN (Pin 1/Pin 5): Shutdown. Pulling theSHDN pinlow puts the LT3008 into a low power state and turns theoutput off. If unused, tie theSHDN pin to VIN. The LT3008does not function if theSHDN pin is not connected. TheSHDN pin cannot be driven below GND unless tied to theIN pin. If theSHDN pin is driven below GND while IN ispowered, the output will turn on.SHDN pin logic cannotbe referenced to a negative rail.
GND (Pins 2, 3, 4/Pin 6): Ground. Connect the bottomof the resistor divider that sets output voltage directly toGND for the best regulation.
IN (Pin 5/Pin 4): Input. The IN pin supplies power to thedevice. The LT3008 requires a bypass capacitor at IN ifthe device is more than six inches away from the maininput lter capacitor. In general, the output impedance ofa battery rises with frequency, so it is advisable to includea bypass capacitor in battery-powered circuits. A bypasscapacitor in the range of 0.1F to 10F will sufce. TheLT3008 withstands reverse voltages on the IN pin withrespect to ground and the OUT pin. In the case of a reversedinput, which occurs with a battery plugged in backwards,the LT3008 acts as if a blocking diode is in series with itsinput. No reverse current ows into the LT3008 and noreverse voltage appears at the load. The device protectsboth itself and the load.OUT (Pin 6/Pins 2, 3): Output. This pin supplies powerto the load. Use a minimum output capacitor of 2.2Fto prevent oscillations. Large load transient applicationsrequire larger output capacitors to limit peak voltagetransients. See the Applications Information section formore information on output capacitance and reverse-outputcharacteristics.
ADJ (Pin 7/Pin 1): Adjust. This pin is the error ampliersinverting terminal. Its 400pA typical input bias currentows out of the pin (see curve of ADJ Pin Bias Current vs
Temperature in the Typical Performance Characteristicsection). The ADJ pin voltage is 600mV referenced to GNand the output voltage range is 600mV to 44.5V.
NC (Pin 8, TSOT-23 Package Only): No Connect. Pin 8is an NC pin in the TSOT-23 package. This pin is not tito any internal circuitry. It may be oated, tied to VIN ortied to GND.
GND (Exposed Pad Pin 7, DFN Package Only): Ground. Theexposed pad (backside) of the DFN package is an electricconnection to GND. To ensure optimum performancsolder Pin 7 to the PCB and tie directly to Pin 6.
SENSE (Pin 7/Pin 1): Sense. For xed voltage versions o
the LT3008 (LT3008-1.2, LT3008-1.5, LT3008-1.8, LT302.5, LT3008-3.3, LT3008-5), the SENSE pin is the inputthe error amplier. Optimum regulation is obtained at thpoint where the SENSE pin is connected to the OUT pinthe regulator. In critical applications, small voltage dropare caused by the resistance (RP) of PC traces betweenthe regulator and the load. These may be eliminated bconnecting the SENSE pin to the output at the load ashown in Figure 1 (Kelvin Sense Connection). Note ththe voltage drop across the external PC traces add to thdropout voltage of the regulator. The SENSE pin bias curreis 1A at the nominal rated output voltage. The SENSE pcan be pulled below ground (as in a dual supply systemwhere the regulator load is returned to a negative supplyand still allow the device to start and operate.
(TSOT-23/DFN)
IN
SHDN
3008 F01
RPOUT
VINSENSE
GND
LT3008
RP
++LOAD
Figure 1. Kelvin Sense Connection
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APPLICATIONS INFORMATION
The LT3008 is a low dropout linear regulator with ultra-low quiescent current and shutdown. Quiescent currentis extremely low at 3A and drops well below 1A inshutdown. The device supplies up to 20mA of output current.Dropout voltage at 20mA is typically 300mV. The LT3008incorporates several protection features, making it ideal foruse in battery-powered systems. The device protects itselfagainst both reverse-input and reverse-output voltages.In battery backup applications, where a backup batteryholds up the output when the input is pulled to ground,the LT3008 acts as if a blocking diode is in series with itsoutput and prevents reverse current ow. In applicationswhere the regulator load returns to a negative supply, theoutput can be pulled below ground by as much as 50Vwithout affecting start-up or normal operation.
Adjustable Operation
The LT3008 has an output voltage range of 0.6V to 44.5V.Figure 2 shows that output voltage is set by the ratio of twoexternal resistors. The IC regulates the output to maintainthe ADJ pin voltage at 600mV referenced to ground. Thecurrent in R1 equals 600mV/R1 and the current in R2 isthe current in R1 minus the ADJ pin bias current. The ADJpin bias current, typically 400pA at 25C, ows out of the
pin. Calculate the output voltage using the formula in Figure2. An R1 value of 619k sets the divider current to 0.97A.Do not make R1s value any greater than 619k to minimizeoutput voltage errors due to the ADJ pin bias current and
to insure stability under minimum load conditions. Ishutdown, the output turns off and the divider current izero. Curves of ADJ Pin Voltage vs Temperature and APin Bias Current vs Temperature appear in the TypicPerformance Characteristics.
Specications for output voltages greater than 0.6V arproportional to the ratio of the desired output voltage t0.6V: VOUT /0.6V. For example, load regulation for an outpcurrent change of 100A to 20mA is 0.5mV typical VOUT = 0.6V. At VOUT = 5V, load regulation is:
5V0.6V
( 0.5mV)= 4.17mV
Table 1 shows resistor divider values for some common output voltages with a resistor divider current oabout 1A.
Figure 2. Adjustable Operation
Table 1. Output Voltage Resistor Divider ValuesVOUT R1 R2
1V 604k 402k
1.2V 590k 590k
1.5V 590k 887k
1.8V 590k 1.18M
2.5V 590k 1.87M
3V 590k 2.37M
3.3V 619k 2.8M
5V 590k 4.32M
IN
SHDN
R2
R1
3008 F02
OUT
VIN
VOUT = 600mV (1 + R2/R1) (IADJ R2)VADJ = 600mVIADJ = 0.4nA at 25COUTPUT RANGE = 0.6V to 44.5V
ADJGND
LT3008
VOUT
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APPLICATIONS INFORMATION
DC BIAS VOLTAGE (V)
C H A N G E I N V A L U E ( % )
3008 F03
20
0
20
40
60
80
1000 4 8 102 6 12 14
X5R
Y5V
16
BOTH CAPACITORS ARE 16V,1210 CASE SIZE, 10F
TEMPERATURE (C)50
40
20
0
20
40
60
80
10025 75
3008 F04
25 0 50 100 125
Y5V
C H A N G E I N V A L U E ( % )
X5R
BOTH CAPACITORS ARE 16V,1210 CASE SIZE, 10F
Figure 3. Ceramic Capacitor DC Bias Characteristics Figure 4. Ceramic Capacitor Temperature Characteristics
Because the ADJ pin is relatively high impedance (de-pending on the resistor divider used), stray capacitancesat this pin should be minimized. Special attention shouldbe given to any stray capacitances that can couple ex-ternal signals onto the ADJ pin, producing undesirableoutput transients or ripple.
Extra care should be taken in assembly when using highvalued resistors. Small amounts of board contaminationcan lead to signicant shifts in output voltage. Appropriatepost-assembly board cleaning measures should beimplemented to prevent board contamination. If theboard is to be subjected to humidity cycling or if boardcleaning measures cannot be guaranteed, consideration
should be given to using resistors an order of magnitudesmaller than in Table 1 to prevent contamination fromcausing unwanted shifts in the output voltage. A xedvoltage option in the LT3008 series will not need thesespecial considerations.
Output Capacitance and Transient Response
The LT3008 is stable with a wide range of output capacitors.The ESR of the output capacitor affects stability, mostnotably with small capacitors. Use a minimum outputcapacitor of 2.2F with an ESR of 3 or less to preventoscillations. The LT3008 is a micropower device and outputload transient response is a function of output capacitance.Larger values of output capacitance decrease the peakdeviations and provide improved transient response forlarger load current changes.
Give extra consideration to the use of ceramic capacitorManufacturers make ceramic capacitors with a variety dielectrics, each with different behavior across temperatuand applied voltage. The most common dielectrics arspecied with EIA temperature characteristic codes Z5U, Y5V, X5R and X7R. The Z5U and Y5V dielecprovide high C-V products in a small package at low cobut exhibit strong voltage and temperature coefcients ashown in Figures 3 and 4. When used with a 5V regulatoa 16V 10F Y5V capacitor can exhibit an effective vaas low as 1F to 2F for the DC bias voltage applied aover the operating temperature range. The X5R anX7R dielectrics yield more stable characteristics and armore suitable for use as the output capacitor. The X7Rtype has better stability across temperature, while thX5R is less expensive and is available in higher valueOne must still exercise care when using X5R and X7capacitors; the X5R and X7R codes only specify operatitemperature range and maximum capacitance changeover temperature. Capacitance change due to DC biawith X5R and X7R capacitors is better than Y5V and Zcapacitors, but can still be signicant enough to dropcapacitor values below appropriate levels. Capacitor Dbias characteristics tend to improve as component case
size increases, but expected capacitance at operatingvoltage should be veried.
Voltage and temperature coefcients are not the onlsources of problems. Some ceramic capacitors have a
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APPLICATIONS INFORMATION
Figure 5. Noise Resulting from Tappingon a Ceramic Capacitor
GND pin current is found by examining the GND PCurrent curves in the Typical Performance Characteristisection. Power dissipation is equal to the sum of the twcomponents listed prior.The LT3008 regulator has internal thermal limiting designto protect the device during overload conditions. Focontinuous normal conditions, do not exceed the maximumjunction temperature rating of 125C. Carefully considall sources of thermal resistance from junction to ambienincluding other heat sources mounted in proximity tthe LT3008. For surface mount devices, heat sinking accomplished by using the heat spreading capabilities othe PC board and its copper traces. Copper board stiffener
and plated through-holes can also be used to spread theheat generated by power devices.
The following tables list thermal resistance for severdifferent board sizes and copper areas. All measurementwere taken in still air on 3/32" FR-4 two-layer boards wone ounce copper.
PCB layers, copper weight, board layout and thermal viaffect the resultant thermal resistance. Although Table2 and 3 provide thermal resistance numbers for 2-layeboards with 1 ounce copper, modern multilayer PCB
provide better performance than found in these tables
100ms/DIV
VOUT500V/DIV
3008 F05
VOUT= 0.6VCOUT= 22F
ILOAD= 10A
piezoelectric response. A piezoelectric device generatesvoltage across its terminals due to mechanical stress,similar to the way a piezoelectric accelerometer ormicrophone works. For a ceramic capacitor, the stresscan be induced by vibrations in the system or thermaltransients. The resulting voltages produced can causeappreciable amounts of noise, especially when a ceramiccapacitor is used for noise bypassing. A ceramic capacitorproduced Figure 5s trace in response to light tapping from apencil. Similar vibration induced behavior can masqueradeas increased output voltage noise.
Table 2: Measured Thermal Resistance for DC PackageCOPPER AREA BOARD
AREATHERMAL RESISTANCE
(JUNCTION-TO-AMBIENTOPSIDE* BACKSIDE
2500mm2 2500mm2 2500mm2 65C/W
1000mm2 2500mm2 2500mm2 70C/W
225mm2 2500mm2 2500mm2 75C/W
100mm2 2500mm2 2500mm2 80C/W
50mm2 2500mm2 2500mm2 85C/W
*Device is mounted on the topside.
Thermal ConsiderationsThe LT3008s maximum rated junction temperature of125C limits its power-handling capability. Two componentscomprise the power dissipated by the device:
1. Output current multiplied by the input/output voltagedifferential: IOUT (VIN VOUT)
2. GND pin current multiplied by the input voltage:IGND VIN
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APPLICATIONS INFORMATION
So,
P = 20mA(12.6V 3.3V) + 0.3mA(12.6V) = 189.8mW
The thermal resistance ranges from 65C/W to 85C/Wdepending on the copper area. So, the junction temperaturrise above ambient approximately equals:
0.1898W(75C/W) = 14.2C
The maximum junction temperature equals the maximumjunction temperature rise above ambient plus the maximumambient temperature or:
TJ(MAX) = 85C + 14.2C = 99.2C
Protection Features
The LT3008 incorporates several protection features thmake it ideal for use in battery-powered circuits. In addition to the normal protection features associated witmonolithic regulators, such as current limiting and thermalimiting, the device also protects against reverse-inpuvoltages, reverse-output voltages and reverse output-toinput voltages.
Current limit protection and thermal overload protection protect the device against current overload conditions at the output of the device. For normal operationdo not exceed a junction temperature of 125C. Thtypical thermal shutdown circuitry temperature thresholis 160C.
The IN pin withstands reverse voltages of 50V. The devilimits current ow to less than 30A (typically less tha1A) and no negative voltage appears at OUT. The devprotects both itself and the load against batteries that arplugged in backwards.
For example, a 4-layer, 1 ounce copper PCB board with3 thermal vias from the DFN exposed backside or the3 fused TSOT-23 GND pins to inner layer GND planes
achieves 45C/W thermal resistance. Demo circuit DC1388As board layout achieves this 45C/W performance.This is approximately a 30% improvement over the lowestnumbers shown in Tables 2 and 3.
Calculating Junction Temperature
Example: Given an output voltage of 3.3V, an input voltagerange of 12V 5%, an output current range of 0mA to 20mAand a maximum ambient temperature of 85C, what willthe maximum junction temperature be for an applicationusing the DC package?
The power dissipated by the device is equal to:
IOUT(MAX) (VIN(MAX) VOUT) + IGND (VIN(MAX))
where,
IOUT(MAX) = 20mA
VIN(MAX) = 12.6V
IGND at (IOUT = 20mA, VIN = 12.6V) = 0.3mA
Table 3: Measured Thermal Resistance for TSOT-23 PackageCOPPER AREA BOARD
AREATHERMAL RESISTANCE
(JUNCTION-TO-AMBIENT)TOPSIDE* BACKSIDE
2500mm2 2500mm2 2500mm2 65C/W
1000mm2 2500mm2 2500mm2 67C/W
225mm2 2500mm2 2500mm2 70C/W
100mm2 2500mm2 2500mm2 75C/W
50mm2 2500mm2 2500mm2 85C/W
*Device is mounted on the topside.
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APPLICATIONS INFORMATION
TheSHDN pin cannot be driven below GND unless tied tothe IN pin. If theSHDN pin is driven below GND while INis powered, the output will turn on.SHDN pin logic cannotbe referenced to a negative rail.The LT3008 incurs no damage if OUT is pulled belowground. If IN is left open circuit or grounded, OUT can bepulled below ground by 50V. No current ows from thepass transistor connected to OUT. However, current owsin (but is limited by) the resistor divider that sets outputvoltage. Current ows from the bottom resistor in thedivider and from the ADJ pins internal clamp through thetop resistor in the divider to the external circuitry pullingOUT below ground. If IN is powered by a voltage source,
OUT sources current equal to its current limit capability andthe LT3008 protects itself by thermal limiting if necessary.In this case, grounding theSHDN pin turns off the LT3008and stops OUT from sourcing current.
The LT3008 incurs no damage if the ADJ pin is pulledabove or below ground by 50V. If IN is left open circuit orgrounded, ADJ acts like a 100k resistor in series with adiode when pulled above or below ground.
In circuits where a backup battery is required, severaldifferent input/output conditions can occur. The output
voltage may be held up while the input is either pulled
OUTPUT AND ADJ VOLTAGE (V)0
60
80
100
8
40
20
50
70
90
30
10
021 43 6 7 95 10
3008 F06
R E V E R S E C U R R E N T ( A )
OUT CURRENT
ADJ CURRENT
Figure 6. Reverse-Output Current
to ground, pulled to some intermediate voltage or is leopen circuit. Current ow back into the output follows thcurve shown in Figure 6.
If the LT3008 IN pin is forced below the OUT pin or tOUT pin is pulled above the IN pin, input current typicadrops to less than 1A. This occurs if the LT3008 input connected to a discharged (low voltage) battery and eithea backup battery or a second regulator circuit holds uthe output. The state of theSHDN pin has no effect in thereverse current if OUT is pulled above IN.
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LT3008 Series
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TYPICAL APPLICATIONS
IN
SHDN
3.3V
3009 TA02
OUT
1F 2.2F
SENSEGND
LT3008-3.3
NO PROTECTIONDIODES NEEDED!
VIN12V
LOAD:SYSTEM MONITOR,
VOLATILE MEMORY, ETC.
IN
SHDN
5V
3008 TA03
OUT FAULT
1FSUPERCAP 2.2F
SENSE
PWRTOMONITORINGCENTER
SENSEGND
GNDLT3008-5
LINE POWERVLINE12V TO 15V
DCHARGE
RLIMIT
LINEINTERRUPT
DETECT
Keep-Alive Power Supply
Last-Gasp Circuit
PACKAGE DESCRIPTION
NOTE:1. DRAWING TO BE MADE A JEDEC PACKAGE OUTLINE M0-229 VARIATION OF (WCCD-2)2. DRAWING NOT TO SCALE3. ALL DIMENSIONS ARE IN MILLIMETERS4. DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE
MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.15mm ON ANY SIDE
2.00 0.10(4 SIDES)
0.75 0.05
PIN 1 BARTOP MARK
(SEE NOTE 6)
0.200 REF
0.00 0.05
0.25 0.05
1.42 0.05(2 SIDES)
RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS
0.61 0.05(2 SIDES)
1.15 0.05
0.70 0.05
2.55 0.05
PACKAGEOUTLINE
0.50 BSC
0.40 0.10
BOTTOM VIEWEXPOSED PAD
0.56 0.05(2 SIDES)
R = 0.125TYP
R = 0.05TYP
1.37 0.05(2 SIDES)
13
64
(DC6) DFN REV B 1309
0.25 0.050.50 BSC
PIN 1 NOTCHR = 0.20 OR0.25 45 CHAMFER
5. EXPOSED PAD SHALL BE SOLDER PLATED6. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON THE
TOP AND BOTTOM OF PACKAGE
DC6 Package6-Lead Plastic DFN (2mm 2mm)
(Reference LTC DWG # 05-08-1703 Rev B)
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1.50 1.75(NOTE 4)
2.80 BSC
0.22 0.368 PLCS (NOTE 3)
DATUM A
0.09 0.20(NOTE 3)TS8 TSOT-23 0710 REV A
2.90 BSC(NOTE 4)
0.65 BSC
1.95 BSC
0.80 0.90
1.00 MAX0.01 0.10
0.20 BSC
0.30 0.50 REF
PIN ONE ID
NOTE:1. DIMENSIONS ARE IN MILLIMETERS2. DRAWING NOT TO SCALE3. DIMENSIONS ARE INCLUSIVE OF PLATING4. DIMENSIONS ARE EXCLUSIVE OF MOLD FLASH AND METAL BURR5. MOLD FLASH SHALL NOT EXCEED 0.254mm6. JEDEC PACKAGE REFERENCE IS MO-193
3.85 MAX
0.40MAX
0.65REF
RECOMMENDED SOLDER PAD LAYOUTPER IPC CALCULATOR
1.4 MIN2.62 REF
1.22 REF
TS8 Package8-Lead Plastic TSOT-23
(Reference LTC DWG # 05-08-1637 Rev A)
PACKAGE DESCRIPTION
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LT3008 Series
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Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no representa-tion that the interconnection of its circuits as described herein will not infringe on existing patent rights.
REVISION HISTORY
REV DATE DESCRIPTION PAGE NUM
B 02/10 Added MP grade in TS8 packageRevised curve G04 in Typical Performance Characteristics
2-4, 67
C 04/12 Claried E-Grade Operating TemperatureUpdated Package Drawings
617, 18
(Revision history begins at Rev B)
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LT3008 Series
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RELATED PARTSPART NUMBER DESCRIPTION COMMENTS
LT1761 100mA, Low Noise Micropower LDO VIN: 1.8V to 20V, VOUT = 1.22V, VDO = 0.3V, IQ = 20A, ISD < 1A, Low Noise: < 20VRMS,Stable with 1F Ceramic Capacitors, ThinSOTTM Package
LT1762 150mA, Low Noise Micropower LDO VIN: 1.8V to 20V, VOUT = 1.22V, VDO = 0.3V, IQ = 25A, ISD < 1A, Low Noise: < 20VRMS,MS8 Package
LT1763 500mA, Low Noise Micropower LDO VIN: 1.8V to 20V, VOUT = 1.22V, VDO = 0.3V, IQ = 30A, ISD < 1A, Low Noise: < 20VRMS,S8 Package
LT1764/LT1764A 3A, Low Noise, Fast TransientResponse LDOs
VIN: 2.7V to 20V, VOUT = 1.21V, VDO = 0.34V, IQ = 1mA, ISD < 1A, Low Noise: < 40VRMS,LT1764A Version Stable with Ceramic Capacitors, DD and TO220-5 Packages
LT1962 300mA, Low Noise Micropower LDO VIN: 1.8V to 20V, VOUT(MIN) = 1.22V, VDO = 0.27V, IQ = 30A, ISD < 1A,Low Noise: < 20VRMS, MS8 Package
LT1963/LT1963A 1.5A, Low Noise, Fast TransientResponse LDOs
VIN: 2.1V to 20V, VOUT(MIN) = 1.21V, VDO = 0.34V, IQ = 1mA, ISD < 1A,Low Noise: < 40VRMS, LT1963A Version Stable with Ceramic Capacitors, DD, TO220-5,SOT223 and S8 Packages
LT3009 20mA, 3A IQ Micropower LDO VIN: 1.6V to 20V, Low IQ: 3A, VDO = 0.28V, 2mm 2mm DFN and SC70-8 Packages
LT3020 100mA, Low Voltage VLDO VIN: 0.9V to 10V, VOUT(MIN) = 0.20V, VDO = 0.15V, IQ = 120A, ISD < 1A, 3mm 3mm DFNand MS8 Packages
LT3021 500mA, Low Voltage VLDO VIN: 0.9V to 10V, VOUT(MIN) = 0.20V, VDO = 0.16V, IQ = 120A, ISD < 3A, 5mm 5mm DFNand SO8 Packages
LT3080/ LT3080-1 1.1A, Parallelable, Low Noise,Low Dropout Linear Regulator
300mV Dropout Voltage (2-Supply Operation), Low Noise: 40VRMS, VIN: 1.2V to 36V,VOUT: 0V to 35.7V, Current-Based Reference with 1-Resistor VOUT Set; Directly Parallelable(No Op Amp Required), Stable with Ceramic Caps, TO-220, SOT-223, MSOP and 3mm 3mm DFN Packages; LT3080-1 Version Has Integrated Internal Ballast Resistor
LT3085 500mA, Parallelable, Low Noise,Low Dropout Linear Regulator
275mV Dropout Voltage (2-Supply Operation), Low Noise: 40VRMS, VIN: 1.2V to 36V,VOUT: 0V to 35.7V, Current-Based Reference with 1-Resistor VOUT Set; Directly Parallelable(No Op Amp Required), Stable with Ceramic Caps, MSOP-8 and 2mm 3mm DFN Packages
ThinSOT is a trademark of Linear Technology Corporation.
IN
SHDN
2.2F
3.3V
3008 TA04a
OUT
1F
SENSE
GND
LT3008-3.3
VIN12V
LOW DUTY CYCLEPULSED LOAD0mA TO 10mA
Low Duty Cycle Applications Average Power Savings for Low Duty Cycle Applicatio0mA to 10mA Pulsed Load, IN = 12V
DUTY CYCLE (%)0.1
70
60
80
90
100
3008 TA04b
40
50
30
1 10
20
10
0
P O W E R S A V I N G S ( % )
10A IQ
100A IQ
30A IQ
TYPICAL APPLICATION