LT3150

LT3021ES8PBF LINEAR_DIMENSIONS | Alldatasheet

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LT3021/LT3021-1.2/ LT3021-1.5/LT3021-1.8 3021fc TYPICAL APPLICATION

FEATURES

APPLICATIONS

DESCRIPTION

500mA, Low Voltage, Very Low Dropout Linear Regulator The L T®3021 is a very low dropout voltage (VLDO™) lin- ear regulator that operates from input supplies down to 0.9V . This device supplies 500mA of output current with a typical dropout voltage of 160mV. The L T3021 is ideal for low input voltage to low output voltage applications, providing comparable electrical efﬁ ciency to that of a switching regulator. The L T3021 regulator optimizes stability and transient response with low ESR, ceramic output capacitors as small as 3.3μF . Other L T3021 features include 0.05% typical line regulation and 0.2% typical load regulation. In shutdown, quiescent current typically drops to 3μA. Internal protection circuitry includes reverse-battery pro- tection, current limiting, thermal limiting with hysteresis, and reverse-current protection. The L T3021 is available as an adjustable output device with an output range down to the 200mV reference. Three ﬁ xed output voltages, 1.2V, 1.5V and 1.8V, are also available. The L T3021 regulator is available in the low proﬁ le (0.75mm) 16-pin (5mm × 5mm) DFN package with ex- posed pad and the 8-lead SO package. 1.8V to 1.5V, 500mA VLDO Regulator n VIN Range: 0.9V to 10V n Dropout Voltage: 160mV Typical n Output Current: 500mA n Adjustable Output (V REF = VOUT(MIN) = 200mV) n Fixed Output Voltages: 1.2V , 1.5V , 1.8V n Stable with Low ESR, Ceramic Output Capacitors (3.3μF Minimum) n 0.2% Load Regulation from 0mA to 500mA n Quiescent Current: 120μA (Typ) n 3μA Typical Quiescent Current in Shutdown n Current Limit Protection n Reverse-Battery Protection n No Reverse Current n Thermal Limiting with Hysteresis n 16-Pin DFN (5mm × 5mm) and 8-Lead SO Packages n Low Current Regulators n Battery-Powered Systems n Cellular Phones n Pagers n Wireless Modems L, L T , L TC and L TM are registered trademarks of Linear Technology Corporation. VLDO is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. Minimum Input Voltage IN SHDN SENSE 3.3μF

3021 TA01

1.8V GND LT3021-1.5 VOUT 1.5V 500mA3.3μF TEMPERATURE (°C) –50 MINIMUM INPUT VOLTAGE (V) 1.1 1.0 0.9 0.8 0.6 0.7 0.5 0.4 0.3 0.2 0.1

3021 TA02

250–25 50 75 125100 IL = 500mA

LT3021/LT3021-1.2/ LT3021-1.5/LT3021-1.8 3021fc ABSOLUTE MAXIMUM RATINGS (Note 1) NC NC IN NC IN NC PGND SHDN NC NC OUT OUT NC NC ADJ AGND TOP VIEW L T3021-ADJ DH PACKAGE 16-LEAD (5mm × 5mm) PLASTIC DFN TJMAX = 125°C, θJA = 35°C/ W*, θJC = 3°C/W** EXPOSED PAD IS GND (PIN 17) CONNECT TO PINS 8, 10 EXPOSED PAD MUST BE SOLDERED TO THE PCB *SEE THE APPLICATIONS INFORMATION SECTION **MEASURED JUNCTION TO PIN 17 NC NC IN NC IN NC PGND SHDN NC NC OUT OUT NC NC SENSE AGND TOP VIEW L T3021-FIXED DH PACKAGE 16-LEAD (5mm × 5mm) PLASTIC DFN TJMAX = 125°C, θJA = 35°C/ W*, θJC = 3°C/W** EXPOSED PAD IS GND (PIN 17) CONNECT TO PINS 8, 10 EXPOSED PAD MUST BE SOLDERED TO THE PCB *SEE THE APPLICATIONS INFORMATION SECTION **MEASURED JUNCTION TO PIN 17 TOP VIEW IN NC PGND SHDN NC OUT ADJ AGND L T3021-ADJ S8 PACKAGE 8-LEAD PLASTIC SO TJMAX = 150°C, θJA = 125°C/ W*, θJC = 40°C/W** *SEE THE APPLICATIONS INFORMATION SECTION **MEASURED JUNCTION TO PIN 6 TOP VIEW IN NC PGND SHDN NC OUT SENSE AGND L T3021-FIXED S8 PACKAGE 8-LEAD PLASTIC SO TJMAX = 150°C, θJA = 125°C/ W*, θJC = 40°C/W** *SEE THE APPLICATIONS INFORMATION SECTION **MEASURED JUNCTION TO PIN 6 PIN CONFIGURATION Operating Junction Temperature Range (E, I Grade) Storage Temperature Range

LT3021/LT3021-1.2/ LT3021-1.5/LT3021-1.8 3021fc ORDER INFORMAITON LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE L T3021EDH#PBF L T3021EDH#TRPBF 3021 16-Lead (5mm × 5mm) Plastic DFN –40°C to 125°C L T3021EDH-1.2#PBF L T3021EDH-1.2#TRPBF 302112 16-Lead (5mm × 5mm) Plastic DFN –40°C to 125°C L T3021EDH-1.5#PBF L T3021EDH-1.5#TRPBF 302115 16-Lead (5mm × 5mm) Plastic DFN –40°C to 125°C L T3021EDH-1.8#PBF L T3021EDH-1.8#TRPBF 302118 16-Lead (5mm × 5mm) Plastic DFN –40°C to 125°C L T3021ES8#PBF L T3021ES8#TRPBF 3021 8-Lead Plastic SO –40°C to 125°C L T3021ES8-1.2#PBF L T3021ES8-1.2#TRPBF 302112 8-Lead Plastic SO –40°C to 125°C L T3021ES8-1.5#PBF L T3021ES8-1.5#TRPBF 302115 8-Lead Plastic SO –40°C to 125°C L T3021ES8-1.8#PBF L T3021ES8-1.8#TRPBF 302118 8-Lead Plastic SO –40°C to 125°C L T3021IS8-1.8#PBF L T3021IS8-1.8#TRPBF 302118 8-Lead Plastic SO –40°C to 125°C LEAD BASED FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE L T3021EDH L T3021EDH#TR 3021 16-Lead (5mm × 5mm) Plastic DFN –40°C to 125°C L T3021EDH-1.2 L T3021EDH-1.2#TR 302112 16-Lead (5mm × 5mm) Plastic DFN –40°C to 125°C L T3021EDH-1.5 L T3021EDH-1.5#TR 302115 16-Lead (5mm × 5mm) Plastic DFN –40°C to 125°C L T3021EDH-1.8 L T3021EDH-1.8#TR 302118 16-Lead (5mm × 5mm) Plastic DFN –40°C to 125°C L T3021ES8 L T3021ES8#TR 3021 8-Lead Plastic SO –40°C to 125°C L T3021ES8-1.2 L T3021ES8-1.2#TR 302112 8-Lead Plastic SO –40°C to 125°C L T3021ES8-1.5 L T3021ES8-1.5#TR 302115 8-Lead Plastic SO –40°C to 125°C L T3021ES8-1.8 L T3021ES8-1.8#TR 302118 8-Lead Plastic SO –40°C to 125°C L T3021IS8-1.8 L T3021IS8-1.8#TR 302118 8-Lead Plastic SO –40°C to 125°C Consult L TC Marketing for parts speciﬁ ed with wider operating temperature ranges. *The temperature grade is identiﬁ ed by a label on the shipping container . For more information on lead free part marking, go to: http://www.linear .com/leadfree/ For more information on tape and reel speciﬁ cations, go to: http://www.linear .com/tapeandreel/

LT3021/LT3021-1.2/ LT3021-1.5/LT3021-1.8 3021fc ELECTRICAL CHARACTERISTICS The l denotes the speciﬁ cations which apply over the full operating temperature range, otherwise speciﬁ cations are at TJ = 25°C. SYMBOL CONDITIONS MIN TYP MAX UNITS Minimum Input Voltage (Notes 5,14) ILOAD = 500mA, TJ > 0°C ILOAD = 500mA, TJ < 0°C 0.9 0.9 1.05 1.10 V V ADJ Pin Voltage (Notes 4, 5) V IN = 1.5V, ILOAD = 1mA 1.15V < VIN < 10V, 1mA < ILOAD < 500mA l 196 193 200 200 204 206 mV mV Regulated Output Voltage (Note 4) L T3021-1.2 V IN = 1.5V, ILOAD = 1mA 1.5V < V IN < 10V, 1mA < ILOAD < 500mA l 1.176 1.157 1.200 1.200 1.224 1.236 V V L T3021-1.5 V IN = 1.8V, ILOAD = 1mA 1.8V < V IN < 10V, 1mA < ILOAD < 500mA l 1.470 1.447 1.500 1.500 1.530 1.545 V V L T3021-1.8 V IN = 2.1V, ILOAD = 1mA 2.1V < V IN < 10V, 1mA < ILOAD < 500mA l 1.764 1.737 1.800 1.800 1.836 1.854 V V Line Regulation (Note 6) L T3021 ΔV IN = 1.15V to 10V, ILOAD = 1mA L T3021-1.2 ΔV IN = 1.5V to 10V, ILOAD = 1mA L T3021-1.5 ΔV IN = 1.8V to 10V, ILOAD = 1mA L T3021-1.8 ΔV IN = 2.1V to 10V, ILOAD = 1mA l l l l –1.75 –10.5 –13 –15.8 +1.75 10.5 15.8 mV mV mV mV Load Regulation (Note 6) L T3021 V IN = 1.15V, ΔILOAD = 1mA to 500mA L T3021-1.2 V IN = 1.5V, ΔILOAD = 1mA to 500mA L T3021-1.5 V IN = 1.8V, ΔILOAD = 1mA to 500mA L T3021-1.8 V IN = 2.1V, ΔILOAD = 1mA to 500mA –7.5 0.4 1.5 7.5 mV mV mV mV Dropout Voltage (Notes 7, 12) I LOAD = 10mA ILOAD = 10mA l 45 75 110 mV mV ILOAD = 500mA ILOAD = 500mA l 155 190 285 mV mV GND Pin Current VIN = VOUT(NOMINAL) + 0.4V (Notes 8, 12) ILOAD = 0mA ILOAD = 10mA ILOAD = 100mA ILOAD = 500mA l l 110 920 2.25 6.20 250 μA μA mA mA Output Voltage Noise C OUT = 4.7μF , ILOAD = 500mA, BW = 10Hz to 100kHz, VOUT = 1.2V 300 μV RMS ADJ Pin Bias Current V ADJ = 0.2V, VIN = 1.2V (Notes 6, 9) 20 50 nA Shutdown Threshold V OUT = Off to On VOUT = On to Off l l 0.25 0.61 0.61 0.9 V V SHDN Pin Current (Note 10) V SHDN = 0V, VIN = 10V VSHDN = 10V, VIN = 10V l l 3 9.5 μA μA Quiescent Current in Shutdown V IN = 6V, VSHDN= 0V 3 9 μA Ripple Rejection (Note 6) L T3021 V IN – VOUT = 1V, VRIP = 0.5VP-P, fRIPPLE = 120Hz, I LOAD = 500mA 70 dB L T3021-1.2 V IN – VOUT = 1V, VRIPPLE = 0.5VP-P, fRIPPLE = 120Hz, I LOAD = 500mA 60 dB L T3021-1.5 V IN – VOUT = 1V, VRIPPLE = 0.5VP-P, fRIPPLE = 120Hz, I LOAD = 500mA 58 dB L T3021-1.8 V IN – VOUT = 1V, VRIPPLE = 0.5VP-P, fRIPPLE = 120Hz, I LOAD = 500mA 56 dB Current Limit (Note 12) V IN = 10V, VOUT = 0V VIN = VOUT(NOMINAL) + 0.5V, ΔVOUT = –5% l 550 1.8 A mA Input Reverse Leakage Current V IN = –10V, VOUT = 0V 1 20 μA Reverse Output Current (Notes 11, 13) L T3021 V OUT = 1.2V, VIN = 0V L T3021-1.2 V OUT = 1.2V, VIN = 0V L T3021-1.5 V OUT = 1.5V, VIN = 0V L T3021-1.8 V OUT = 1.8V, VIN = 0V 0.5 μA μA μA μA

LT3021/LT3021-1.2/ LT3021-1.5/LT3021-1.8 3021fc TYPICAL PERFORMANCE CHARACTERISTICS Dropout Voltage Dropout Voltage Minimum Input Voltage OUTPUT CURRENT (mA) DROPOUT VOL TAGE (mV) 250 225 200 150 175 125 100

3021 G01

TJ = 125°C TJ = 25°C TEMPERATURE (°C) –50 DROPOUT VOL TAGE (mV) 250 225 200 150 175 125 100

3021 G02

250–25 50 75 125100 IL = 1mA IL = 100mA IL = 250mA IL = 500mA IL = 50mA IL = 10mA VOUT = 1.2V TEMPERATURE (°C) –50 MINIMUM INPUT VOL TAGE (V) 1.2 1.1 1.0 0.9 0.8 0.6 0.7 0.5 0.4 0.3 0.2

3021 G16

250–25 50 75 125100 IL = 500mA Note 1: Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. Exposure to any Absolute Maximum Rating condition for extended periods may affect device reliability and lifetime. Note 2: The L T3021 regulators are tested and speciﬁ ed under pulse load conditions such that T J ≈ TA. The L T3021E regulators are 100% tested at TA = 25°C. Performance at –40°C and 125°C is assured by design, characterization and correlation with statistical process controls. The L T3021I regulators are guaranteed over the full –40ºC to 125ºC operating junction temperature range. Note 3: This IC includes overtemperature protection that is intended to protect the device during momentary overload conditions. Junction temperature will exceed 125°C when overtemperature protection is active. Continuous operation above the speciﬁ ed maximum operating junction temperature may impair device reliability. Note 4: Maximum junction temperature limits operating conditions. The regulated output voltage speciﬁ cation does not apply for all possible combinations of input voltage and output current. Limit the output current range if operating at maximum input voltage. Limit the input voltage range if operating at maximum output current. Note 5: Typically the L T3021 supplies 500mA output current with a 1V input supply. The guranteed minimum input voltage for 500mA output current is 1.10V . Note 6: The L T3021 is tested and speciﬁ ed for these conditions with an external resistor divider (20k and 30.1k) setting V OUT to 0.5V. The external resistor divider adds 10μA of output load current. The line regulation and load regulation speciﬁ cations refer to the change in the 0.2V reference voltage, not the 0.5V output voltage. Speciﬁ cations for ﬁ xed output voltage devices are referred to the output voltage. Note 7: Dropout voltage is the minimum input to output voltage differential needed to maintain regulation at a speciﬁ ed output current. In dropout the output voltage equals: (V IN – VDROPOUT). Note 8: GND pin current is tested with VIN = VOUT(NOMINAL) + 0.4V and a current source load. GND pin current will increase in dropout. See GND pin current curves in the Typical Performance Characteristics section. Note 9: Adjust pin bias current ﬂ ows out of the ADJ pin. Note 10: Shutdown pin current ﬂ ows into the SHDN pin. Note 11: Reverse output current is tested with IN grounded and OUT forced to the rated output voltage. This current ﬂ ows into the OUT pin and out of the GND pin. For ﬁ xed voltage devices this includes the current in the output resistor divider . Note 12: The L T3021 is tested and speciﬁ ed for these conditions with an external resistor divider (20k and 100k) setting V OUT to 1.2V. The external resistor divider adds 10μA of load current. Note 13: Reverse current is higher for the case of (rated_output) < VOUT < VIN, because the no-load recovery circuitry is active in this region and is trying to restore the output voltage to its nominal value. Note 14: Minimum input voltage is the minimum voltage required by the control circuit to regulate the output voltage and supply the full 500mA rated current. This speciﬁ cation is tested at V OUT = 0.5V. At higher output voltages the minimum input voltage required for regulation will be equal to the regulated output voltage V OUT plus the dropout voltage. ELECTRICAL CHARACTERISTICS The l denotes the speciﬁ cations which apply over the full operating temperature range, otherwise speciﬁ cations are at TJ = 25°C.

LT3021/LT3021-1.2/ LT3021-1.5/LT3021-1.8 3021fc TYPICAL PERFORMANCE CHARACTERISTICS ADJ Pin Voltage ADJ Pin Bias Current Quiescent Current Output Voltage Output Voltage Output Voltage Quiescent Current Quiescent Current Quiescent Current TEMPERATURE (°C) –50 ADJ PIN VOL TAGE (mV) 206 204 202 198 200 196 194

3021 G04

250–25 50 75 125100 TEMPERATURE (°C) –50 ADJ PIN BIAS CURRENT (nA)

3021 G11

250–25 50 75 125100 TEMPERATURE (°C) –50 250 225 200 150 175 125 100 250–25 50 75 125100 QUIESCENT CURRENT (μA)

3021 G05

VIN = 6V VOUT = 1.2V IL = 0 VSHDN = VIN VSHDN = 0V TEMPERATURE (°C) –50 OUTPUT VOL TAGE (V) 1.23 1.22 1.21 1.20 1.19 1.18 1.17 25 75

3021 G28

–25 0 50 100 125 ILOAD = 1mA TEMPERATURE (°C) –50 OUTPUT VOL TAGE (V) 1.53 1.52 1.51 1.50 1.49 1.48 1.47 25 75

3021 G23

–25 0 50 100 125 ILOAD = 1mA TEMPERATURE (°C) –50 OUTPUT VOL TAGE (V) 1.83 1.82 1.81 1.80 1.79 1.78 1.77 25 75

3021 G22

–25 0 50 100 125 ILOAD = 1mA INPUT VOL TAGE (V) QUIESCENT CURRENT (mA) 3.0 2.5 2.0 1.0 1.5 0.5

3021 G03

VSHDN = VIN VSHDN = 0V VOUT = 1.2V IL = 0 TJ = 25°C INPUT VOL TAGE (V) QUIESCENT CURRENT (mA) 3.0 2.5 2.0 1.5 1.0 0.5 246 8

3021 G26

VOUT = 1.5V IL = 0 TJ = 25°C VSHDN = 0V VSHDN = VIN INPUT VOL TAGE (V) QUIESCENT CURRENT (mA) 3.0 2.5 2.0 1.5 1.0 0.5 246 8

3021 G27

VOUT = 1.8V IL = 0 TJ = 25°C VSHDN = 0V VSHDN = VIN

LT3021/LT3021-1.2/ LT3021-1.5/LT3021-1.8 3021fc TYPICAL PERFORMANCE CHARACTERISTICS GND Pin Current GND Pin Current GND Pin Current GND Pin Current vs ILOAD SHDN Pin Threshold SHDN Pin Input Current SHDN Pin Input Current Current Limit Reverse Output Current INPUT VOL TAGE (V) GND PIN CURRENT (mA)

3021 G06

VOUT = 1.2V TJ = 25°C RL = 12Ω IL = 100mA RL = 2.4Ω IL = 500mA RL = 4.8Ω IL = 250mA RL = 24Ω IL = 50mA RL = 120Ω IL = 10mA RL = 1.2k, IL = 1mA INPUT VOL TAGE (V) GND PIN CURRENT (mA) 246 8

3021 G24

VOUT = 1.5V TJ = 25°CRL = 3Ω IL = 500mA RL = 6Ω IL = 250mA RL = 15Ω IL = 100mA RL = 30Ω IL = 50mA RL = 1.5k, IL = 1mA RL = 150Ω IL = 10mA INPUT VOL TAGE (V) GND PIN CURRENT (mA) 246 8

3021 G25

VOUT = 1.8V TJ = 25°C RL = 3.6Ω IL = 500mA RL = 7.2Ω IL = 250mA RL = 18Ω IL = 100mA RL = 36Ω IL = 50mA RL = 1.8k, IL = 1mA RL = 180Ω IL = 10mA LOAD CURRENT (mA) GND PIN CURRENT (mA)

3021 G07

VSHDN = 10V TEMPERATURE (°C) –50 SHDN PIN THRESHOLD (V) 1.0 0.9 0.8 0.6 0.7 0.5 0.4 0.3 0.2 0.1

3021 G08

250–25 50 75 125100 IL = 1mA SHDN PIN VOL TAGE (V) SHDN PIN INPUT CURRENT (μA) 5.0 4.5 4.0 3.0 3.5 2.5 2.0 1.5 1.0 0.5

3021 G09

TEMPERATURE (°C) –50

3021 G10

250–25 50 75 125100 VSHDN = 10V SHDN PIN INPUT CURRENT (μA) TEMPERATURE (°C) –50

3021 G12

250–25 50 75 125100 VOUT = 0V VIN = 1.7V VIN = 10V CURRENT LIMIT (A) 2.0 1.8 1.6 1.2 1.4 1.0 0.8 0.6 0.4 0.2 TEMPERATURE (°C) –50

3021 G13

250–25 50 75 125100 VIN = 0V VOUT = 1.2V REVERSE OUTPUT CURRENT (μA) 500 450 400 300 350 250 200 150 100

LT3021/LT3021-1.2/ LT3021-1.5/LT3021-1.8 3021fc TYPICAL PERFORMANCE CHARACTERISTICS Input Ripple Rejection Input Ripple Rejection Load Regulation ΔIL = 1mA to 500mA No-Load Recovery Threshold Output Noise Spectral Density RMS Output Noise vs Load Current (10Hz to 100kHz) T ransient Response FREQUENCY (Hz) INPUT RIPPLE REJECTION (dB) 10 1k 10k 1M

3021 G14

VIN = 1.5V + 50mVRMS RIPPLE VOUT = 0.5V IL = 500mA COUT = 4.7μF COUT = 22μF TEMPERATURE (°C) –50 INPUT RIPPLE REJECTION (dB) 100

3021 G15

250–25 50 75 125100 VIN = 1.5V + 0.5VP-P RIPPLE AT 120Hz VOUT = 0.5V IL = 500mA TEMPERATURE (°C) –50 LOAD REGULATION (mV) 2.5 2.0 1.5 0.5 1.0 –0.5 –1.0 –1.5 –2.0 –2.5

3021 G17

250–25 50 75 125100 VIN = 1.15V VOUT = 0.5V *LOAD REGULATION NUMBER REFERS TO CHANGE IN THE 200mV REFERENCE VOL TAGE OUTPUT OVERSHOOT (%) OUTPUT SINK CURRENT (mA)

3021 G20

FREQUENCY (Hz) OUTPUT NOISE SPECTRAL DENSITY (μV/√Hz) 0.1 0.01 1k 100k 1M100 10k

3021 G18

VOUT = 1.2V IL = 500mA COUT = 4.7μF LOAD CURRENT (mA) OUTPUT NOISE (μVRMS) 300 250 200 150 100 0.01 1 10 100

3021 G19

0.1 VOUT = 1.2V COUT = 4.7μF 50μs/DIV IOUT = 50mA TO 500mA VIN = 1.5V VOUT = 1.2V COUT = 22μF

3021 G21

LT3021/LT3021-1.2/ LT3021-1.5/LT3021-1.8 3021fc PIN FUNCTIONS OUT (Pins 3, 4/Pin 2): These pins supply power to the load. Use a minimum output capacitor of 3.3μF to prevent oscil- lations. Applications with large load transients require larger output capacitors to limit peak voltage transients. See the Applications Information section for more information on output capacitance and reverse output characteristics. SENSE (Pin 7/Pin 3, Fixed Voltage Device Only): This pin is the sense point for the internal resistor divider . It should be tied directly to the OUT pins for best results. ADJ (Pin 7/Pin 3): This pin is the inverting terminal to the error ampliﬁ er . Its typical input bias current of 20nA ﬂ ows out of the pin (see curve of ADJ Pin Bias Current vs Tem- perature in the Typical Performance Characteristics). The ADJ pin reference voltage is 200mV (referred to GND). AGND (Pin 8/Pin 4): Ground. PGND (Pins 10, 17/Pin 6): Ground. SHDN (Pin 9/Pin 5): The SHDN pin puts the L T3021 into a low power state. Pulling the SHDN pin low turns the output off. Drive the SHDN pin with either logic or an open collector/drain device with a pull-up resistor . The pull-up resistor supplies the pull-up current to the open collector/ drain logic, normally several microamperes, and the SHDN pin current, typically 2.5μA. If unused, connect the SHDN pin to VIN. The L T3021 does not function if the SHDN pin is not connected. IN (Pins 12, 14/Pin 8): These pins supply power to the device. The L T3021 requires a bypass capacitor at IN if it is more than six inches away from the main input ﬁ lter capacitor . The output impedance of a battery rises with frequency, so include a bypass capacitor in battery-pow- ered circuits. A bypass capacitor in the range of 3.3μF to 10μF sufﬁ ces. The L T3021 withstands reverse voltages on the IN pin with respect to ground and the OUT pin. In the case of a reversed input, which occurs if a battery is plugged in backwards, the L T3021 acts as if a diode is in series with its input. No reverse current ﬂ ows into the L T3021 and no reverse voltage appears at the load. The device protects itself and the load. EXPOSED PAD (Pin 17, DH16 Package Only): Ground. Solder Pin 17 to the PCB ground. Connect directly to Pins 8, 10 for best performance. NC (Pins 1, 2, 5, 6, 11, 13, 15, 16/Pins 1, 7): No Connect. No connect pins may be ﬂ oated, tied to IN or tied to GND. (DH Package/S8 Package) BLOCK DIAGRAM (DH Package/S8 Package) SHUTDOWN CURRENT GAIN THERMAL SHUTDOWN 3021 BD ERROR AMP NO-LOAD RECOVERY IN (12, 14/8) OUT (3,4/2) OUT SENSE (7/3) NOTE: FOR L T3021 ADJUST PIN (7/3) IS CONNECTED TO THE ADJUST PIN, R1 AND R2 ARE EXTERNAL. FOR L T3021-1.X PIN (7/3) IS CONNECTED TO THE OUTPUT SENSE PIN, R1 AND R2 ARE INTERNAL. GND (8,10,17/4,6) ADJ (7/3) SHDN (9/5) 200mV 212mV BIAS CURRENT AND REFERENCE GENERATOR FIXED VOUT 1.2V 1.5V 1.8V 20k 20k 20k 100k 130k 160k 25k

output current and dropout voltage is typically 155mV. start-up or normal operation. tain the ADJ pin voltage at 200mV referenced to ground. Typical Performance Characteristics section. capacitors, but is optimized for low ESR ceramic capacitors. load transient response is a function of output capacitance. oscillation (200Hz/8mV P-P at 1.2V output) can occur . Give extra consideration to the use of ceramic capacitors. but exhibit strong voltage and temperature coefﬁ cients. both exhibit excellent voltage coefﬁ cient characteristics. comparisons between Y5V and X5R material. induced by vibrations in the system or thermal transients. Figure 1. Adjustable Operation

3021 F01

few microfarads of output capacitance. down the bias current/reference generator circuitry.

Output current multiplied by the input-to-output voltage
GND pin current multiplied by the input voltage:

Figure 2. Ceramic Capacitor DC Bias Characteristics Figure 3. Ceramic Capacitor Temperature Characteristics Figure 4. Noise Resulting from Tapping on a Ceramic CapacitorDC BIAS VOL TAGE (V)

3021 F02

1210 CASE SIZE, 10μF

3021 F03

3021 F04

ceed the maximum junction temperature rating of 125°C. in proximity to the L T3021. of the package on the topside (component side) of a PCB. FR-4 board with one ounce copper . Table 1. Measured Thermal Resistance For DH Package Table 2. Measured Thermal Resistance For S8 Package *Device is mounted on topside. that make it ideal for use in battery-powered circuits. exceed a junction temperature of 125°C.

LT3021/LT3021-1.2/ LT3021-1.5/LT3021-1.8 3021fc APPLICATIONS INFORMATION The L T3021 incurs no damage if OUT is pulled below ground. If IN is left open circuit or grounded, OUT can be pulled below ground by 10V. No current ﬂ ows from the pass transistor connected to OUT. However, current ﬂ ows in (but is limited by) the resistor divider that sets the out- put voltage. Current ﬂ ows from the bottom resistor in the divider and from the ADJ pin’s internal clamp through the top resistor in the divider to the external circuitry pulling OUT below ground. If IN is powered by a voltage source, OUT sources current equal to its current limit capability and the L T3021 protects itself by thermal limiting. In this case, grounding SHDN turns off the L T3021 and stops OUT from sourcing current. The L T3021 incurs no damage if the ADJ pin is pulled above or below ground by 10V. If IN is left open circuit or grounded and ADJ is pulled above ground, ADJ acts like a 25k resistor in series with a 1V clamp (one Schottky diode in series with one diode). ADJ acts like a 25k resistor in series with a Schottky diode if pulled below ground. If IN is powered by a voltage source and ADJ is pulled below its reference voltage, the L T3021 attempts to source its current limit capability at OUT. The output voltage increases to V IN – VDROPOUT with VDROPOUT set by whatever load current the L T3021 supports. This condition can potentially dam- age external circuitry powered by the L T3021 if the output voltage increases to an unregulated high voltage. If IN is powered by a voltage source and ADJ is pulled above its reference voltage, two situations can occur. If ADJ is pulled slightly above its reference voltage, the L T3021 turns off the pass transistor , no output current is sourced and the output voltage decreases to either the voltage at ADJ or less. If ADJ is pulled above its no load recovery threshold, the no load recovery circuitry turns on and attempts to sink current. OUT is actively pulled low and the output voltage clamps at a Schottky diode above ground. Please note that the behavior described above applies to the L T3021 only. If a resistor divider is connected under the same conditions, there will be additional V/R current. In circuits where a backup battery is required, several different input/output conditions can occur. The output voltage may be held up while the input is either pulled to ground, pulled to some intermediate voltage or is left open circuit. In the case where the input is grounded, there is less than 1μA of reverse output current. If the L T3021 IN pin is forced below the OUT pin or the OUT pin is pulled above the IN pin, input current drops to less than 10μA typically. This occurs if the L T3021 input is connected to a discharged (low voltage) battery and either a backup battery or a second regulator circuit holds up the output. The state of the SHDN pin has no effect on the reverse output current if OUT is pulled above IN. Input Capacitance and Stability The L T3021 is designed to be stable with a minimum capacitance of 3.3μF placed at the IN pin. Ceramic capaci- tors with very low ESR may be used. However, in cases where a long wire is used to connect a power supply to the input of the L T3021 (and also from the ground of the L T3021 back to the power supply ground), use of low value input capacitors combined with an output load current of 20mA or greater may result in an unstable application. This is due to the inductance of the wire forming an LC tank circuit with the input capacitor and not a result of the L T3021 being unstable. The self-inductance, or isolated inductance, of a wire is directly proportional to its length. However, the diameter of a wire does not have a major inﬂ uence on its self-in- ductance. For example, the self inductance of a 2-AWG isolated wire with a diameter of 0.26 in. is about half the inductance of a 30-AWG wire with a diameter of 0.01 in. One foot of 30-AWG wire has 465nH of self inductance. The overall self-inductance of a wire can be reduced in two ways. One is to divide the current ﬂ owing towards the L T3021 between two parallel conductors and ﬂ ows in the same direction in each. In this case, the farther the wires are placed apart from each other, the more inductance will be reduced, up to a 50% reduction when placed a few inches apart. Splitting the wires basically connects two equal inductors in parallel. However, when placed in close proximity from each other, mutual inductance is added to the overall self inductance of the wires. The most effective way to reduce overall inductance is to place the forward and return-current conductors (the wire for the input and the wire for ground) in very close proximity. T wo 30-AWG wires separated by 0.02 in. reduce the overall self-induc- tance to about one-ﬁ fth of a single isolated wire.

LT3021/LT3021-1.2/ LT3021-1.5/LT3021-1.8 3021fc APPLICATIONS INFORMATION If the L T3021 is powered by a battery mounted in close proximity on the same circuit board, a 3.3μF input capacitor is sufﬁ cient for stability. However, if the L T3021 is powered by a distant supply, use a larger value input capacitor fol- lowing the guideline of roughly 1μF (in addition to the 3.3μF minimum) per 8 inches of wire length. As power supply output impedance may vary, the minimum input capaci- tance needed to stabilize the application may also vary. Extra capacitance may also be placed directly on the output of the power supply; however, this will require an order of magnitude more capacitance as opposed to placing extra capacitance in close proximity to the L T3021. Furthermore, series resistance may be placed between the supply and the input of the L T3021 to stabilize the application; as little as 0.1Ω to 0.5Ω will sufﬁ ce. PACKAGE DESCRIPTION 16-Lead Plastic DFN (5mm × 5mm) (Reference L TC DWG # 05-08-1709) 5.00 ±0.10 5.00 ±0.10 NOTE: 1. DRAWING PROPOSED TO BE MADE VARIATION OF VERSION (WJJD-1) IN JEDEC PACKAGE OUTLINE MO-229 2. DRAWING NOT TO SCALE 3. ALL DIMENSIONS ARE IN MILLIMETERS 4. 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 5. EXPOSED PAD SHALL BE SOLDER PLATED 6. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON THE 0.40 ± 0.05 BOTTOM VIEW—EXPOSED PAD 3.45 ± 0.10 (2 SIDES) 0.75 ±0.05 R = 0.115 TYP R = 0.20 TYP 4.10 ±0.10 (2 SIDES) 169 PIN 1 TOP MARK (SEE NOTE 6)

0.200 REF

0.00 – 0.05 (DH16) DFN 0204 0.25 ± 0.05 PIN 1 NOTCH

0.50 BSC

4.10 ±0.05 (2 SIDES) RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS 3.45 ±0.05 (2 SIDES) 4.10 ±0.05 0.70 ±0.05 5.50 ±0.05 PACKAGE OUTLINE 0.25 ± 0.05

LT3021/LT3021-1.2/ LT3021-1.5/LT3021-1.8 3021fc 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. PACKAGE DESCRIPTION 8-Lead Plastic Small Outline (Narrow .150 Inch) (Reference L TC DWG # 05-08-1610) .016 – .050 (0.406 – 1.270) .010 – .020 0°– 8 ° TYP .008 – .010 (0.203 – 0.254) SO8 0303 .053 – .069 (1.346 – 1.752) .014 – .019 (0.355 – 0.483) TYP .004 – .010 (0.101 – 0.254) .050 (1.270) BSC 1 2 3 4 .150 – .157 (3.810 – 3.988) NOTE 3 8 7 6 5 .189 – .197 (4.801 – 5.004) NOTE 3 .228 – .244 (5.791 – 6.197) .245 MIN .160 ±.005 RECOMMENDED SOLDER PAD LAYOUT .045 ±.005 .050 BSC .030 ±.005 TYP INCHES (MILLIMETERS) NOTE: 1. DIMENSIONS IN 2. DRAWING NOT TO SCALE 3. THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .006" (0.15mm)

LT3021/LT3021-1.2/ LT3021-1.5/LT3021-1.8 3021fc Linear Technology Corporation 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 ● FAX: (408) 434-0507 ● www.linear .com © LINEAR TECHNOLOGY CORPORATION 2005 LT 0608 REV C • PRINTED IN USA RELATED PARTS PART NUMBER DESCRIPTION COMMENTS L T1121/L T1121HV 150mA, Micropower LDOs V IN: 4.2V to 30V/36V, VOUT: 3.75V to 30V, VDO = 0.42V, IQ = 30μA, ISD = 16μA, Reverse-Battery Protection, SOT-223, S8, Z Packages L T1129 700mA, Micropower LDO V IN: 4.2V to 30V, VOUT: 3.75V to 30V, VDO = 0.4V, IQ = 50μA, ISD = 16μA, DD, SOT-223, S8, TO220-5, TSSOP20 Packages L T1761 100mA, Low Noise Micropower LDO V IN: 1.8V to 20V, VOUT: 1.22V to 20V, VDO = 0.3V, IQ = 20μA, ISD < 1μA, Low Noise: < 20μVRMSP-P, Stable with 1μF Ceramic Capacitor, ThinSOT Package L T1762 150mA, Low Noise Micropower LDO V IN: 1.8V to 20V, VOUT: 1.22V to 20V, VDO = 0.3V, IQ = 25μA, ISD < 1μA, Low Noise: <20μV RMSP-P, MS8 Package L T1763 500mA, Low Noise Micropower LDO V IN: 1.8V to 20V, VOUT: 1.22V to 20V, VDO = 0.3V, IQ = 30μA, ISD < 1μA, Low Noise: < 20μVRMSP-P, S8 Package L T1764/L T1764A 3A, Low Noise, Fast T ransient Response LDOs V IN: 2.7V to 20V, VOUT: 1.21V to 20V, VDO = 0.34V, IQ = 1mA, ISD < 1μA, Low Noise: <40μVRMSP-P, “A” Version Stable with Ceramic Capacitors, DD, TO220-5 Packages L TC1844 150mA, Low Noise, Micropower VLDO V IN: 1.6V to 6.5V, VOUT(MIN) = 1.25V, VDO = 0.09V, IQ = 35μA, ISD < 1μA, Low Noise: < 30μVRMS, ThinSOT Package L T1962 300mA, Low Noise Micropower LDO V IN: 1.8V to 20V, VOUT: 1.22V to 20V , VDO = 0.27V, IQ = 30μA, ISD < 1 μA, Low Noise: < 20μVRMSP-P, MS8 Package L T1963/L T1963A 1.5A, Low Noise, Fast T ransient Response LDOs V IN: 2.1V to 20V, VOUT: 1.21V to 20V, VDO = 0.34V, IQ = 1mA, ISD < 1μA, Low Noise: < 40μVRMSP-P, “A” Version Stable with Ceramic Capacitors, DD, TO220-5, SOT223, S8 Packages L T3010 50mA, High Voltage, Micropower LDO V IN: 3V to 80V, VOUT: 1.275V to 60V, VDO = 0.3V, IQ = 30μA, ISD < 1μA, Low Noise: <100μVRMSP-P, Stable with 1μF Output Capacitor, Exposed MS8 Package L T3020 100mA, Low Voltage LDO V IN: 0.9V to 10V, VOUT: 0.2V to 5V (min), VDO = 0.15V, IQ = 120μA, Noise: <250μVRMSP-P, Stable with 2.2μF Ceramic Capacitors, DFN-8, MS8 Packages Stable with 1μF Ceramic Capacitors, DFN-6 Package VDO = 0.1V, IQ = 950μA, Stable with 10μF Ceramic Capacitors, 10-Lead MSOP and DFN-10 Packages L T3150 Low V IN, Fast T ransient Response, VLDO Controller V IN: 1.1V to 10V, VOUT: 1.21V to 10V, VDO = Set by External MOSFET RDS(ON), 1.4MHz Boost Converter Generates Gate Drive, SSOP16 Package

Summary

500mA, Low Voltage, Very Low Dropout Linear Regulator

Description