LT1761_1 LINER | Alldatasheet
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100mA, Low Noise, LDO Micropower Regulators in SOT-23 ■ Low Noise: 20μVRMS (10Hz to 100kHz) ■ Low Quiescent Current: 20μA ■ Wide Input Voltage Range: 1.8V to 20V ■ Output Current: 100mA ■ Very Low Shutdown Current: < 0.1μA ■ Low Dropout Voltage: 300mV at 100mA ■ Fixed Output Voltages: 1.2V, 1.5V, 1.8V, 2V, 2.5V, 2.8V, 3V, 3.3V, 5V ■ Adjustable Output from 1.22V to 20V ■ Stable with 1μF Output Capacitor ■ Stable with Aluminum, Tantalum or Ceramic Capacitors ■ Reverse Battery Protected ■ No Reverse Current ■ No Protection Diodes Needed ■ Overcurrent and Overtemperature Protected ■ Available in Tiny 5-Lead SOT-23 Package The LT 1761 series are micropower, low noise, low dropout regulators. With an external 0.01 μF bypass capacitor, output noise drops to 20μVRMS over a 10Hz to 100kHz bandwidth. Designed for use in battery-powered systems, the low 20μA quiescent current makes them an ideal choice. In shutdown, quiescent current drops to less than 0.1μA. The devices are capable of operating over an input voltage from 1.8V to 20V, and can supply 100mA of output current with a dropout voltage of 300mV. Quies- cent current is well controlled, not rising in dropout as it does with many other regulators. The LT1761 regulators are stable with output capacitors as low as 1 μF. Small ceramic capacitors can be used without the series resistance required by other regulators. Internal protection circuitry includes reverse battery pro- tection, current limiting, thermal limiting and reverse current protection. The device is available in fixed output 5V, and as an adjustable device with a 1.22V reference voltage. The LT1761 regulators are available in the 5-lead SOT-23 package. 10Hz to 100kHz Output Noise 5V Low Noise Regulator ■ Cellular Phones ■ Pagers ■ Battery-Powered Systems ■ Frequency Synthesizers ■ Wireless Modems IN SHDN 0.01μF 10μF
1761 TA01
5.4V TO 20V BYP GND LT1761-5 5V AT100mA 20μVRMS NOISE 1μF VOUT 100μV/DIV 20μVRMS
1761 G48
, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners.
(Note 1) LT1761ES5-BYP ORDER PART NUMBER TJMAX = 150°C, θJA = 250°C/ W SEE THE APPLICATIONS INFORMATION SECTION.
5 OUT
4 ADJ
4 BYP
Operating Junction Temperature Range S5 PART MARKING TJMAX = 150°C, θJA = 250°C/ W SEE THE APPLICATIONS INFORMATION SECTION. LT1761ES5-SD ORDER PART NUMBER S5 PART MARKING LTGC LTGH LT1761ES5-1.2 LT1761ES5-1.5 LT1761ES5-1.8 LT1761MPS5-1.8 LT1761ES5-2 LT1761ES5-2.5 LT1761ES5-2.8 LT1761ES5-3 LT1761ES5-3.3 LT1761ES5-5 ORDER PART NUMBER S5 PART MARKING LTCDS LTMT LTJM LTDCH LTJE LTGD LTLB LTGE LTGF LTGG TJMAX = 150°C, θJA = 250°C/ W SEE THE APPLICATIONS INFORMATION SECTION. ABSOLUTE AXI U RATI GSW WW U PACKAGE/ORDER I FOR ATIOUU W Consult LTC Marketing for parts specified with wider operating temperature ranges. Order Options Tape and Reel: Add #TR Lead Free: Add #PBF Lead Free Tape and Reel: Add #TRPBF Lead Free Part Marking: http://www.linear.com/leadfree/
The ● denotes specifications which apply over the full operating temperature range, otherwise specifications are TA = 25°C. (Note 2) PARAMETER CONDITIONS MIN TYP MAX UNITS Minimum Input Voltage (Notes 3, 11) I LOAD = 100mA ● 1.8 2.3 V Regulated Output Voltage LT1761-1.2 V IN = 2V, ILOAD = 1mA 1.185 1.2 1.215 V (Note 4) 2.3V < V IN < 20V, 1mA < ILOAD < 50mA ● 1.170 1.2 1.230 V 2.3V < VIN < 20V, 1mA < ILOAD < 100mA ● 1.150 1.2 1.240 V LT1761-1.5 V IN = 2V, ILOAD = 1mA 1.478 1.5 1.522 V 2.5V < VIN < 20V, 1mA < ILOAD < 50mA ● 1.457 1.5 1.538 V 2.5V < VIN < 20V, 1mA < ILOAD < 50mA ● 1.436 1.5 1.555 V 2.8V < VIN < 20V, 1mA < ILOAD < 50mA ● 1.750 1.8 1.845 V 2.8V < VIN < 20V, 1mA < ILOAD < 100mA ● 1.725 1.8 1.860 V LT1761-2 V IN = 2.5V, ILOAD = 1mA 1.970 2 2.030 V 3V < VIN < 20V, 1mA < ILOAD < 50mA ● 1.945 2 2.045 V 3V < VIN < 20V, 1mA < ILOAD < 100mA ● 1.920 2 2.060 V LT1761-2.5 V IN = 3V, ILOAD = 1mA 2.465 2.5 2.535 V 3.5V < VIN < 20V, 1mA < ILOAD < 50mA ● 2.435 2.5 2.565 V 3.5V < VIN < 20V, 1mA < ILOAD < 100mA ● 2.415 2.5 2.575 V 3.8V < VIN < 20V, 1mA < ILOAD < 50mA ● 2.732 2.8 2.868 V 3.8V < VIN < 20V, 1mA < ILOAD < 100mA ● 2.706 2.8 2.884 V LT1761-3 V IN = 3.5V, ILOAD = 1mA 2.960 3 3.040 V 4V < VIN < 20V, 1mA < ILOAD < 50mA ● 2.930 3 3.070 V 4V < VIN < 20V, 1mA < ILOAD < 100mA ● 2.900 3 3.090 V 4.3V < VIN < 20V, 1mA < ILOAD < 50mA ● 3.230 3.3 3.370 V 4.3V < VIN < 20V, 1mA < ILOAD < 100mA ● 3.190 3.3 3.400 V LT1761-5 V IN = 5.5V, ILOAD = 1mA 4.935 5 5.065 V 6V < VIN < 20V, 1mA < ILOAD < 50mA ● 4.900 5 5.100 V 6V < VIN < 20V, 1mA < ILOAD < 100mA ● 4.850 5 5.120 V ADJ Pin Voltage LT1761 V IN = 2V, ILOAD = 1mA 1.205 1.220 1.235 V (Note 3, 4) 2.3V < V IN < 20V, 1mA < ILOAD < 50mA ● 1.190 1.220 1.250 V 2.3V < VIN < 20V, 1mA < ILOAD < 100mA ● 1.170 1.220 1.260 V Line Regulation LT1761-1.2 ΔVIN = 2V to 20V, ILOAD = 1mA ● 11 0 m V LT1761-1.5 ΔVIN = 2V to 20V, ILOAD = 1mA ● 11 0 m V LT1761-1.8 ΔVIN = 2.3V to 20V, ILOAD = 1mA ● 11 0 m V LT1761-2 ΔVIN = 2.5V to 20V, ILOAD = 1mA ● 11 0 m V LT1761-2.5 ΔVIN = 3V to 20V, ILOAD = 1mA ● 11 0 m V LT1761-2.8 ΔVIN = 3.3V to 20V, ILOAD = 1mA ● 11 0 m V LT1761-3 ΔVIN = 3.5V to 20V, ILOAD = 1mA ● 11 0 m V LT1761-3.3 ΔVIN = 3.8V to 20V, ILOAD = 1mA ● 11 0 m V LT1761-5 ΔVIN = 5.5V to 20V, ILOAD = 1mA ● 11 0 m V LT1761 (Note 3) ΔVIN = 2V to 20V, ILOAD = 1mA ● 11 0 m V
ELECTRICAL CHARACTERISTICS
PARAMETER CONDITIONS MIN TYP MAX UNITS Load Regulation LT1761-1.2 V IN = 2.3V, ΔILOAD = 1mA to 50mA 1 6 mV VIN = 2.3V, ΔILOAD = 1mA to 50mA ● 12 mV VIN = 2.3V, ΔILOAD = 1mA to 100mA 1 12 mV VIN = 2.3V, ΔILOAD = 1mA to 100mA ● 50 mV LT1761-1.5 V IN = 2.5V, ΔILOAD = 1mA to 50mA 10 20 mV VIN = 2.5V, ΔILOAD = 1mA to 50mA ● 35 mV VIN = 2.5V, ΔILOAD = 1mA to 50mA 14 30 mV VIN = 2.5V, ΔILOAD = 1mA to 50mA ● 55 mV LT1761-1.8 V IN = 2.8V, ΔILOAD = 1mA to 50mA 10 20 mV VIN = 2.8V, ΔILOAD = 1mA to 50mA ● 35 mV VIN = 2.8V, ΔILOAD = 1mA to 100mA 15 30 mV VIN = 2.8V, ΔILOAD = 1mA to 100mA ● 60 mV LT1761-2 V IN = 3V, ΔILOAD = 1mA to 50mA 10 20 mV VIN = 3V, ΔILOAD = 1mA to 50mA ● 35 mV VIN = 3V, ΔILOAD = 1mA to 100mA 15 35 mV VIN = 3V, ΔILOAD = 1mA to 100mA ● 65 mV LT1761-2.5 V IN = 3.5V, ΔILOAD = 1mA to 50mA 10 20 mV VIN = 3.5V, ΔILOAD = 1mA to 50mA ● 35 mV VIN = 3.5V, ΔILOAD = 1mA to 100mA 20 40 mV VIN = 3.5V, ΔILOAD = 1mA to 100mA ● 80 mV LT1761-2.8 V IN = 3.8V, ΔILOAD = 1mA to 50mA 10 20 mV VIN = 3.8V, ΔILOAD = 1mA to 50mA ● 38 mV VIN = 3.8V, ΔILOAD = 1mA to 100mA 20 40 mV VIN = 3.8V, ΔILOAD = 1mA to 100mA ● 86 mV LT1761-3 V IN = 4V, ΔILOAD = 1mA to 50mA 10 20 mV VIN = 4V, ΔILOAD = 1mA to 50mA ● 40 mV VIN = 4V, ΔILOAD = 1mA to 100mA 20 40 mV VIN = 4V, ΔILOAD = 1mA to 100mA ● 90 mV LT1761-3.3 V IN = 4.3V, ΔILOAD = 1mA to 50mA 10 20 mV VIN = 4.3V, ΔILOAD = 1mA to 50mA ● 40 mV VIN = 4.3V, ΔILOAD = 1mA to 100mA 20 40 mV VIN = 4.3V, ΔILOAD = 1mA to 100mA ● 100 mV LT1761-5 V IN = 6V, ΔILOAD = 1mA to 50mA 15 30 mV VIN = 6V, ΔILOAD = 1mA to 50mA ● 60 mV VIN = 6V, ΔILOAD = 1mA to 100mA 25 65 mV VIN = 6V, ΔILOAD = 1mA to 100mA ● 150 mV LT1761 (Note 3) VIN = 2.3V, ΔILOAD = 1mA to 50mA 1 6 mV VIN = 2.3V, ΔILOAD = 1mA to 50mA ● 12 mV VIN = 2.3V, ΔILOAD = 1mA to 100mA 1 12 mV VIN = 2.3V, ΔILOAD = 1mA to 100mA ● 50 mV Dropout Voltage I LOAD = 1mA 0.10 0.15 V VIN = VOUT(NOMINAL) ILOAD = 1mA ● 0.19 V (Notes 5, 6, 11) I LOAD = 10mA 0.17 0.22 V ILOAD = 10mA ● 0.29 V ILOAD = 50mA 0.24 0.28 V ILOAD = 50mA ● 0.38 V ILOAD = 100mA 0.30 0.35 V ILOAD = 100mA ● 0.45 V The ● denotes specifications which apply over the full operating temperature range, otherwise specifications are TA = 25°C. (Note 2)
PARAMETER CONDITIONS MIN TYP MAX UNITS GND Pin Current I LOAD = 0mA ● 20 45 μA VIN = VOUT(NOMINAL) ILOAD = 1mA ● 55 100 μA (Notes 5, 7) I LOAD = 10mA ● 230 400 μA ILOAD = 50mA ● 12 m A ILOAD = 100mA ● 2.2 4 mA Output Voltage Noise C OUT = 10μF, CBYP = 0.01μF, ILOAD = 100mA, BW = 10Hz to 100kHz 20 μVRMS ADJ Pin Bias Current (Notes 3, 8) 30 100 nA Shutdown Threshold V OUT = Off to On ● 0.8 2 V VOUT = On to Off ● 0.25 0.65 V SHDN Pin Current V SHDN = 0V ● 0 0.5 μA (Note 9) V SHDN = 20V ● 13 μA Quiescent Current in Shutdown V IN = 6V, VSHDN = 0V 0.01 0.1 μA Ripple Rejection (Note 3) V IN – VOUT = 1.5V (Avg), VRIPPLE = 0.5VP-P, fRIPPLE = 120Hz, 55 65 dB ILOAD = 50mA Current Limit V IN = 7V, VOUT = 0V 200 mA VIN = VOUT(NOMINAL) + 1V or 2.3V (Note 12), ΔVOUT = –5% ● 110 mA Input Reverse Leakage Current V IN = –20V, V OUT = 0V ● 1m A Reverse Output Current LT1761-1.2 V OUT = 1.2V, VIN < 1.2V 10 20 μA (Note 10) LT1761-1.5 V OUT = 1.5V, VIN < 1.5V 10 20 μA LT1761-1.8 V OUT = 1.8V, VIN < 1.8V 10 20 μA LT1761-2 V OUT = 2V, VIN < 2V 10 20 μA LT1761-2.5 V OUT = 2.5V, VIN < 2.5V 10 20 μA LT1761-2.8 V OUT = 2.8V, VIN < 2.8V 10 20 μA LT1761-3 V OUT = 3V, VIN < 3V 10 20 μA LT1761-3.3 V OUT = 3.3V, VIN < 3.3V 10 20 μA LT1761-5 V OUT = 5V, VIN < 5V 10 20 μA LT1761 (Note 3) VOUT = 1.22V, VIN < 1.22V 5 10 μA 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 LT1761 regulators are tested and specified under pulse load conditions such that TJ ≈ TA. The LT1761E is 100% production tested at TA = 25°C. Performance at –40 °C and 125°C is assured by design, characterization and correlation with statistical process controls. The LT1761MP is 100% tested and guaranteed over the – 55°C to 125°C temperature range. Note 3: The LT1761 (adjustable versions) are tested and specified for these conditions with the ADJ pin connected to the OUT pin. Note 4: Operating conditions are limited by maximum junction temperature. The regulated output voltage specification will not apply for all possible combinations of input voltage and output current. When operating at maximum input voltage, the output current range must be limited. When operating at maximum output current, the input voltage range must be limited. Note 5: To satisfy requirements for minimum input voltage, the LT1761 (adjustable version) is tested and specified for these conditions with an external resistor divider (two 250k resistors) for an output voltage of 2.44V. The external resistor divider will add a 5μA DC load on the output. Note 6: Dropout voltage is the minimum input to output voltage differential needed to maintain regulation at a specified output current. In dropout, the output voltage will be equal to: VIN – VDROPOUT. Note 7: GND pin current is tested with VIN = VOUT(NOMINAL) or VIN = 2.3V (whichever is greater) and a current source load. This means the device is tested while operating in its dropout region or at the minimum input voltage specification. This is the worst-case GND pin current. The GND pin current will decrease slightly at higher input voltages. Note 8: ADJ pin bias current flows into the ADJ pin. Note 9: SHDN pin current flows into the SHDN pin. Note 10: Reverse output current is tested with the IN pin grounded and the OUT pin forced to the rated output voltage. This current flows into the OUT pin and out the GND pin. Note 11: For the LT1761, LT1761-1.2, LT1761-1.5, LT1761-1.8 and LT1761-2 dropout voltage will be limited by the minimum input voltage specification under some output voltage/load conditions. See the curve of Minimum Input Voltage in the Typical Performance Characteristics. Note 12: To satisfy requirements for minimum input voltage, current limit is tested at V IN = VOUT(NOMINAL) + 1V or VIN = 2.3V, whichever is greater. The ● denotes specifications which apply over the full operating temperature range, otherwise specifications are TA = 25°C. (Note 2)
TEMPERATURE (°C) –50 OUTPUT VOLTAGE (V) 100
1761 G05
1.220 1.215 1.210 1.205 1.200 1.195 1.190 1.185 1.180 –25 25 75 125 IL = 1mA TYPICAL PERFOR A CE CHARACTERISTICS UW OUTPUT CURRENT (mA) 500 450 400 350 300 250 200 150 100 DROPOUT VOLTAGE (mV)
1761 G01
0 1 02 03 0 40 50 60 70 80 90 100 TJ ≤ 125°C TJ ≤ 25°C = TEST POINTS TEMPERATURE (°C) –50 QUIESCENT CURRENT (μA) 100
1761 G03
–25 25 75 125 VIN = 6V RL = ∞ (250k FOR LT1761-BYP, -SD) IL = 0 (5μA FOR LT1761-BYP, -SD) VSHDN = VIN VSHDN = 0V TEMPERATURE (°C) –50 OUTPUT VOLTAGE (V) 100
1761 G06
1.84 1.83 1.82 1.81 1.80 1.79 1.78 1.77 1.76 –25 25 75 125 IL = 1mA Guaranteed Dropout Voltage Quiescent Current LT1761-1.8 Output Voltage Dropout Voltage TEMPERATURE (°C) –50 DROPOUT VOLTAGE (mV) 0 50 75 1761 G01.1 –25 25 100 125 IL = 100mA IL = 50mA IL = 10mA IL = 1mA 500 450 400 350 300 250 200 150 100 OUTPUT CURRENT (mA) 500 450 400 350 300 250 200 150 100 DROPOUT VOLTAGE (mV)
1761 G00
0 1 02 03 0 40 50 60 70 80 90 100 TJ = 125°C TJ = 25°C Typical Dropout Voltage TEMPERATURE (°C) –50 OUTPUT VOLTAGE (V) 100
1761 G51
1.528 1.521 1.514 1.507 1.500 1.493 1.486 1.479 1.472 –25 25 75 125 IL = 1mA LT1761-1.5 Output Voltage TEMPERATURE (°C) –50 OUTPUT VOLTAGE (V) 100
1761 G08
2.54 2.53 2.52 2.51 2.50 2.49 2.48 2.47 2.46 –25 25 75 125 IL = 1mA LT1761-2.5 Output Voltage TEMPERATURE (°C) –50 OUTPUT VOLTAGE (V) 100
1761 G07
2.04 2.03 2.02 2.01 2.00 1.99 1.98 1.97 1.96 –25 25 75 125 IL = 1mA LT1761-2 Output Voltage LT1761-1.2 Output Voltage
INPUT VOLTAGE (V) QUIESCENT CURRENT (μA) 250 225 200 175 150 125 100
1761 G10b
TJ = 25°C RL = ∞ VSHDN = 0V VSHDN = VIN TYPICAL PERFOR A CE CHARACTERISTICS UW LT1761-5 Output Voltage TEMPERATURE (°C) –50 OUTPUT VOLTAGE (V) 100
1761 G12
5.08 5.06 5.04 5.02 5.00 4.98 4.96 4.94 4.92 –25 25 75 125 IL = 1mA LT1761-2.8 Output Voltage TEMPERATURE (°C) –50 OUTPUT VOLTAGE (V) 100
1761 G09
3.060 3.045 3.030 3.015 3.000 2.985 2.970 2.955 2.940 –25 25 75 125 IL = 1mA LT1761-3 Output Voltage LT1761-3.3 Output Voltage TEMPERATURE (°C) –50 OUTPUT VOLTAGE (V) 100
1761 G11
3.360 3.345 3.330 3.315 3.300 3.285 3.270 3.255 3.240 –25 25 75 125 IL = 1mA TEMPERATURE (°C) –50 OUTPUT VOLTAGE (V) 100
1761 G52
2.84 2.83 2.82 2.81 2.80 2.79 2.78 2.77 2.76 –25 25 75 125 IL = 1mA LT1761-BYP, LT1761-SD ADJ Pin Voltage TEMPERATURE (°C) –50 ADJ PIN VOLTAGE (V) 100
1761 G10
1.240 1.235 1.230 1.225 1.220 1.215 1.210 1.205 1.200 –25 25 75 125 IL = 1mA LT1761-1.5 Quiescent Current INPUT VOLTAGE (V) QUIESCENT CURRENT (μA) 200 175 150 125 100
1761 G53
VSHDN = VIN TJ = 25°C RL = ∞ VSHDN = 0V INPUT VOLTAGE (V) QUIESCENT CURRENT (μA) 200 175 150 125 100
1761 G18
VSHDN = VIN TJ = 25°C RL = ∞ VSHDN = 0V LT1761-1.8 Quiescent Current INPUT VOLTAGE (V) QUIESCENT CURRENT (μA) 200 175 150 125 100
1761 G19
VSHDN = VIN TJ = 25°C RL = ∞ VSHDN = 0V LT1761-2 Quiescent Current LT1761-1.2 Quiescent Current
INPUT VOLTAGE (V) 2.50 2.25 2.00 1.75 1.50 1.25 1.00 0.75 0.50 0.25 GND PIN CURRENT (mA)
1761 G17b
TJ = 25°C *FOR VOUT = 1.2V RL = 12Ω IL = 100mA* RL = 24Ω IL = 50mA* RL = 120Ω IL = 10mA* RL = 1.2k IL = 1mA* INPUT VOLTAGE (V) 2.50 2.25 2.00 1.75 1.50 1.25 1.00 0.75 0.50 0.25 GND PIN CURRENT (mA)
1761 G02
TJ = 25°C *FOR VOUT = 1.8V RL = 18Ω IL = 100mA* RL = 36Ω IL = 50mA* RL = 180Ω IL = 10mA* RL = 1.8k IL = 1mA* LT1761-1.8 GND Pin Current LT1761-3.3 Quiescent Current LT1761-5 Quiescent Current INPUT VOLTAGE (V) QUIESCENT CURRENT (μA) 200 175 150 125 100
1761 G15
VSHDN = VIN TJ = 25°C RL = ∞ VSHDN = 0V INPUT VOLTAGE (V) QUIESCENT CURRENT (μA) 200 175 150 125 100
1761 G16
VSHDN = VIN TJ = 25°C RL = ∞ VSHDN = 0V INPUT VOLTAGE (V) 02 6 1 0 1 4 1 8 QUIESCENT CURRENT (μA) 4 8 12 16
1761 G17
TJ = 25°C RL = 250k IL = 5μA VSHDN = VIN VSHDN = 0V LT1761-BYP, LT1761-SD Quiescent Current LT1761-3 Quiescent Current INPUT VOLTAGE (V) QUIESCENT CURRENT (μA) 200 175 150 125 100
1761 G14
VSHDN = VIN TJ = 25°C RL = ∞ VSHDN = 0V LT1761-2.5 Quiescent Current INPUT VOLTAGE (V) QUIESCENT CURRENT (μA) 200 175 150 125 100
1761 G13
VSHDN = VIN TJ = 25°C RL = ∞ VSHDN = 0V LT1761-2.8 Quiescent Current INPUT VOLTAGE (V) QUIESCENT CURRENT (μA) 200 175 150 125 100
1761 G54
TJ = 25°C RL = ∞ VSHDN = 0V VSHDN = VIN LT1761-1.5 GND Pin Current INPUT VOLTAGE (V) 2.50 2.25 2.00 1.75 1.50 1.25 1.00 0.75 0.50 0.25 GND PIN CURRENT (mA)
1761 G55
TJ = 25°C *FOR VOUT = 1.5V RL = 15Ω IL = 100mA* RL = 30Ω IL = 50mA* RL = 150Ω IL = 10mA* RL = 1.5k IL = 1mA* TYPICAL PERFOR A CE CHARACTERISTICS UW LT1761-1.2 GND Pin Current
INPUT VOLTAGE (V) 2.50 2.25 2.00 1.75 1.50 1.25 1.00 0.75 0.50 0.25 GND PIN CURRENT (mA)
1761 G24
TJ = 25°C *FOR VOUT = 1.22V RL = 12.2Ω IL = 100mA* RL = 24.4Ω IL = 50mA* RL = 122Ω IL = 10mA* RL = 1.22k IL = 1mA* OUTPUT CURRENT (mA) 2.50 2.25 2.00 1.75 1.50 1.25 1.00 0.75 0.50 0.25 GND PIN CURRENT (mA)
1761 G25
0 1 02 03 0 40 50 60 70 80 90 100 VIN = VOUT(NOMINAL) + 1V LT1761-BYP, LT1761-SD GND Pin Current GND Pin Current vs ILOAD TEMPERATURE (°C) –50 SHDN PIN THRESHOLD (V) 1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 50 75
1761 G26
–25 25 100 125 IL = 1mA SHDN Pin Threshold (On-to-Off) TYPICAL PERFOR A CE CHARACTERISTICS UW INPUT VOLTAGE (V) 2.50 2.25 2.00 1.75 1.50 1.25 1.00 0.75 0.50 0.25 GND PIN CURRENT (mA)
1761 G04
TJ = 25°C *FOR VOUT = 2V RL = 20Ω IL = 100mA* RL = 40Ω IL = 50mA* RL = 200Ω IL = 10mA* RL = 2k IL = 1mA* LT1761-2 GND Pin Current LT1761-2.5 GND Pin Current INPUT VOLTAGE (V) 2.50 2.25 2.00 1.75 1.50 1.25 1.00 0.75 0.50 0.25 GND PIN CURRENT (mA)
1761 G20
TJ = 25°C *FOR VOUT = 2.5V RL = 25Ω IL = 100mA RL = 50Ω IL = 50mA* RL = 250Ω IL = 10mA* RL = 2.5k IL = 1mA* LT1761-3 GND Pin Current INPUT VOLTAGE (V) 2.50 2.25 2.00 1.75 1.50 1.25 1.00 0.75 0.50 0.25 GND PIN CURRENT (mA)
1761 G21
TJ = 25°C *FOR VOUT = 3V RL = 30Ω IL = 100mA* RL = 60Ω IL = 50mA* RL = 300Ω IL = 10mA* RL = 3k IL = 1mA* INPUT VOLTAGE (V) 2.50 2.25 2.00 1.75 1.50 1.25 1.00 0.75 0.50 0.25 GND PIN CURRENT (mA)
1761 G22
TJ = 25°C *FOR VOUT = 3.3V RL = 33Ω IL = 100mA* RL = 66Ω IL = 50mA* RL = 330Ω IL = 10mA* RL = 3.3k IL = 1mA* LT1761-3.3 GND Pin Current INPUT VOLTAGE (V) 2.50 2.25 2.00 1.75 1.50 1.25 1.00 0.75 0.50 0.25 GND PIN CURRENT (mA)
1761 G23
TJ = 25°C *FOR VOUT = 5V RL = 50Ω IL = 100mA RL = 100Ω IL = 50mA* RL = 500Ω IL = 10mA* RL = 5k IL = 1mA* LT1761-5 GND Pin Current LT1761-2.8 GND Pin Current INPUT VOLTAGE (V) 2.50 2.25 2.00 1.75 1.50 1.25 1.00 0.75 0.50 0.25 GND PIN CURRENT (mA)
1761 G56
TJ = 25°C *FOR VOUT = 2.8V RL = 28Ω IL = 100mA RL = 56Ω IL = 50mA* RL = 280Ω IL = 10mA* RL = 2.8k IL = 1mA*
Reverse Output Current Reverse Output Current OUTPUT VOLTAGE (V) 100 REVERSE OUTPUT CURRENT (μA)
1761 G33
TJ = 25°C VIN = 0V CURRENT FLOWS INTO OUTPUT PIN V OUT = VADJ (LT1761-BYP, -SD) LT1761-BYP LT1761-SD LT1761-2 LT1761-3.3 LT1761-5 LT1761-1.8 LT1761-1.5 LT1761-2.5 LT1761-2.8 LT1761-3 LT1761-1.2 TEMPERATURE (°C) –50 REVERSE OUTPUT CURRENT (μA) 25.0 22.5 20.0 17.5 15.0 12.5 10.0 7.5 5.0 2.5 0 50 75
1761 G34
–25 25 100 125 VIN = 0V VOUT = 1.22V (LT1761-BYP, -SD) VOUT = 1.2V (LT1761-1.2) VOUT = 1.5V (LT1761-1.5) VOUT = 1.8V (LT1761-1.8) VOUT = 2V (LT1761-2) VOUT = 2.5V (LT1761-2.5) VOUT = 2.8V (LT1761-2.8) VOUT = 3V (LT1761-3) VOUT = 3.3V (LT1761-3.3) VOUT = 5V (LT1761-5) LT1761-BYP,-SD FREQUENCY (Hz) RIPPLE REJECTION (dB) 10 1k 10k 1M
1761 G35
IL = 100mA VIN = VOUT(NOMINAL) + 1V + 50mVRMS RIPPLE CBYP = 0 COUT = 1μF COUT = 10μF LT1761-BYP LT1761-5 Input Ripple Rejection TYPICAL PERFOR A CE CHARACTERISTICS UW SHDN Pin Input Current ADJ Pin Bias Current Current Limit TEMPERATURE (°C) –50 SHDN PIN INPUT CURRENT (μA) 0 50 75
1761 G29
–25 25 100 125 VSHDN = 20V 1.4 1.2 1.0 0.8 0.6 0.4 0.2 TEMPERATURE (°C) –50 ADJ PIN BIAS CURRENT (nA) 100 0 50 75
1761 G30
–25 25 100 125 INPUT VOLTAGE (V) SHORT-CIRCUIT CURRENT (mA) 2 4 5
1761 G31
VOUT = 0V TJ = 25°C Current Limit TEMPERATURE (°C) –50 CURRENT LIMIT (mA) 0 50 75
1761 G32
–25 25 100 125 350 300 250 200 150 100 VIN = 7V VOUT = 0V SHDN PIN VOLTAGE (V) 1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 SHDN PIN INPUT CURRENT (μA)
1761 G28
TEMPERATURE (°C) –50 SHDN PIN THRESHOLD (V) 1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 50 75
1761 G27
–25 25 100 125 IL = 100mA IL = 1mA SHDN Pin Threshold (Off-to-On)
Output Noise Spectral Density FREQUENCY (Hz) 10 1k 10k 100k
1761 G41
0.1 0.01 OUTPUT NOISE SPECTRAL DENSITY (μV/√Hz) COUT = 10μF CBYP = 0 IL = 100mA LT1761-BYP, -SD, 1.2 LT1761-5 LT1761-3.3 LT1761-2.8,-3 LT1761-2.5 LT1761-1.8 LT1761-2 LT1761-1.5 FREQUENCY (Hz) 10 1k 10k 100k
1761 G42
0.1 0.01 OUTPUT NOISE SPECTRAL DENSITY (μV/√Hz) LT1761-BYP LT1761-5 CBYP = 1000pF CBYP = 0.01μF CBYP = 100pF COUT = 10μF IL = 100mA CBYP (pF) OUTPUT NOISE (μVRMS) 140 120 100 100 1k 10k
1761 G43
COUT = 10μF IL = 100mA f = 10Hz TO 100kHz LT1761-5 LT1761-3.3 LT1761-3 LT1761-2.8 LT1761-2.5 LT1761-1.5 LT1761-1.8, -2 LT1761-BYP, -1.2 Output Noise Spectral Density RMS Output Noise vs Bypass Capacitor TYPICAL PERFOR A CE CHARACTERISTICS UW FREQUENCY (Hz) RIPPLE REJECTION (dB) 10 1k 10k 1M
1761 G36
IL = 100mA VIN = VOUT(NOMINAL) + 1V + 50mVRMS RIPPLE COUT = 10μF CBYP = 0.01μF CBYP = 100pF CBYP = 1000pF TEMPERATURE (°C) –50 RIPPLE REJECTION (dB) 100
1761 G37
–25 25 75 125 VIN = VOUT (NOMINAL) + 1V + 0.5VP-P RIPPLE AT f = 120Hz I L = 50mA LT1761-5 Input Ripple Rejection Input Ripple Rejection LT1761-BYP, LT1761-SD Minimum Input Voltage Load Regulation ΔIL = 1mA to 50mA TEMPERATURE (°C) –50 MINIMUM INPUT VOLTAGE (V) 2.5 2.0 1.5 1.0 0.5 0 50 75
1761 G38
–25 25 100 125 IL = 100mA IL = 50mA TEMPERATURE (°C) –50 LOAD REGULATION (mV) 100
1761 G39
–10 –15 –20 –25 –3 0 –35 –40 –25 25 75 125 LT1761-BYP, -SD, -1.2 LT1761-1.8 LT1761-1.5 LT1761-2 LT1761-2.5 LT1761-2.8 LT1761-3 LT1761-3.3 LT1761-5 TEMPERATURE (°C) –50 LOAD REGULATION (mV) 100
1761 G40
–10 –20 –30 –40 –50 –60 –70 –80 –90 –100 –25 25 75 125 LT1761-3 LT1761-2 LT1761-2.5 LT1761-2.8 LT1761-5 LT1761-3.3 LT1761-BYP, -SD, -1.2 LT1761-1.8 LT1761-1.5 Load Regulation ΔIL = 1mA to 100mA
LT1761-5 Transient Response CBYP = 0 TIME (μs) 0.2 0.1 –0.1 –0.2 OUTPUT VOLTAGE DEVIATION (V) 100 LOAD CURRENT (mA)
1761 G49
VIN = 6V CIN = 10μF COUT = 10μF TIME (μs) 0.04 0.02 –0.02 –0.04 OUTPUT VOLTAGE DEVIATION (V) 100 LOAD CURRENT (mA)
1761 G50
04 0 6 0 1 0 020 80 120 140 180160 200 VIN = 6V CIN = 10μF COUT = 10μF LT1761-5 Transient Response CBYP = 0.01μF TYPICAL PERFOR A CE CHARACTERISTICS UW LT1761-5 10Hz to 100kHz Output Noise C BYP = 0 VOUT 100μV/DIV LT1761-5 10Hz to 100kHz Output Noise CBYP = 100pF 1ms/DIV COUT = 10μF IL = 100mA 1761 G46 VOUT 100μV/DIV 1ms/DIV COUT = 10μF IL = 100mA 1761 G45 LOAD CURRENT (mA) 0.01 OUTPUT NOISE (μVRMS) 160 140 120 100 0.1 1
1761 G44
COUT = 10μF LT1761-5 LT1761-5 LT1761-BYP LT1761-BYP CBYP = 0 CBYP = 0.01μF RMS Output Noise vs Load Current (10Hz to 11kHz) LT1761-5 10Hz to 100kHz Output Noise CBYP = 1000pF VOUT 100μV/DIV LT1761-5 10Hz to 100kHz Output Noise C BYP = 0.01μF 1ms/DIV COUT = 10μF IL = 100mA 1761 G48 VOUT 100μV/DIV 1ms/DIV COUT = 10μF IL = 100mA 1761 G47
function if the SHDN pin is not connected. For the LT1761-BYP, the SHDN pin is internally connected to VIN. BYP (Pins 3/4, Fixed/-BYP Devices): Bypass. The BYP pin is used to bypass the reference of the LT1761 regula- tors to achieve low noise performance from the regulator. The BYP pin is clamped internally to ±0.6V (one V BE) from ground. A small capacitor from the output to this pin will bypass the reference to lower the output voltage noise. A maximum value of 0.01μF can be used for reducing output voltage noise to a typical 20μV RMS over a 10Hz to 100kHz bandwidth. If not used, this pin must be left unconnected. ADJ (Pin 4, Adjustable Devices Only): Adjust Pin. For the adjustable LT1761, this is the input to the error amplifier. This pin is internally clamped to ±7V. It has a bias current of 30nA which flows into the pin (see curve of ADJ Pin Bias Current vs Temperature in the Typical Performance Char- acteristics section). The ADJ pin voltage is 1.22V referenced to ground and the output voltage range is 1.22V to 20V. OUT (Pin 5): Output. The output supplies power to the load. A minimum output capacitor of 1 μF is required to prevent oscillations. Larger output capacitors will be required for applications with large transient loads to limit peak voltage transients. See the Applications Information section for more information on output capacitance and reverse output characteristics. IN (Pin 1): Input. Power is supplied to the device through the IN pin. A bypass capacitor is required on this pin if the device is more than six inches away from the main input filter capacitor. In general, the output impedance of a battery rises with frequency, so it is advisable to include a bypass capacitor in battery-powered circuits. A bypass capacitor in the range of 1 μF to 10 μF is sufficient. The LT1761 regulators are designed to withstand reverse voltages on the IN pin with respect to ground and the OUT pin. In the case of a reverse input, which can happen if a battery is plugged in backwards, the device will act as if there is a diode in series with its input. There will be no reverse current flow into the regulator and no reverse voltage will appear at the load. The device will protect both itself and the load. GND (Pin 2): Ground. SHDN (Pin 3, Fixed/-SD Devices): Shutdown. The SHDN pin is used to put the LT1761 regulators into a low power shutdown state. The output will be off when the SHDN pin is pulled low. The SHDN pin can be driven either by 5V logic or open-collector logic with a pull-up resistor. The pull-up resistor is required to supply the pull-up current of the open-collector gate, normally several microamperes, and the SHDN pin current, typically 1 μA. If unused, the SHDN pin must be connected to V IN. The device will not UUUPI FU CTIO S
Figure 1. The value of R1 should be no greater than 250k
1761 F01
Figure 1. Adjustable Operation pin tied to the OUT pin for an output voltage of 1.22V. bypass capacitor and 10μF output capacitor.
Figure 2. Stability
1761 F02
capacitance used, while the maximum ESR is 3Ω. temperature coefficients as shown in Figures 3 and 4. Figure 4. Ceramic Capacitor Temperature CharacteristicsFigure 3. Ceramic Capacitor DC Bias Characteristics
1761 F04
1210 CASE SIZE, 10μF
1761 F03
masquerade as increased output voltage noise.
- Output current multiplied by the input/output voltage
- GND pin current multiplied by the input voltage:
sum of the two components listed above. all sources of thermal resistance from junction to ambient. Table 1. Measured Thermal Resistance *Device is mounted on topside. Figure 5. Noise Resulting from Tapping on a Ceramic Capacitor
Calculating Junction Temperature Example: Given an output voltage of 3.3V, an input voltage range of 4V to 6V, an output current range of 0mA to 50mA and a maximum ambient temperature of 50°C, what will the maximum junction temperature be? The power dissipated by the device will be equal to: IOUT(MAX)(VIN(MAX) – VOUT) + IGND(VIN(MAX)) where, IOUT(MAX) = 50mA VIN(MAX) = 6V IGND at (IOUT = 50mA, VIN = 6V) = 1mA So, The thermal resistance will be in the range of 125°C/W to 150°C/W depending on the copper area. So the junction temperature rise above ambient will be approximately equal to: The maximum junction temperature will then be equal to the maximum junction temperature rise above ambient plus the maximum ambient temperature or: T Protection Features The LT1761 regulators incorporate several protection features which make them ideal for use in battery-powered circuits. In addition to the normal protection features associated with monolithic regulators, such as current limiting and thermal limiting, the devices are protected against reverse input voltages, reverse output voltages and reverse voltages from output to input. Current limit protection and thermal overload protection are intended to protect the device against current overload conditions at the output of the device. For normal opera- tion, the junction temperature should not exceed 125°C. The input of the device will withstand reverse voltages of 20V. Current flow into the device will be limited to less than 1mA (typically less than 100μA) and no negative voltage will appear at the output. The device will protect both itself and the load. This provides protection against batteries which can be plugged in backward. The output of the LT1761-X can be pulled below ground without damaging the device. If the input is left open circuit or grounded, the output can be pulled below ground by 20V. For fixed voltage versions, the output will act like a large resistor, typically 500k Ω or higher, limiting current flow to typically less than 100 μA. For adjustable versions, the output will act like an open circuit; no current will flow out of the pin. If the input is powered by a voltage source, the output will source the short-circuit current of the device and will protect itself by thermal limiting. In this case, grounding the SHDN pin will turn off the device and stop the output from sourcing the short-circuit current. The ADJ pin of the adjustable device can be pulled above or below ground by as much as 7V without damaging the device. If the input is left open circuit or grounded, the ADJ pin will act like an open circuit when pulled below ground and like a large resistor (typically 100k) in series with a diode when pulled above ground. In situations where the ADJ pin is connected to a resistor divider that would pull the ADJ pin above its 7V clamp voltage if the output is pulled high, the ADJ pin input current must be limited to less than 5mA. For example, a resistor divider is used to provide a regulated 1.5V output APPLICATIO S I FOR ATIOWU UU
from the 1.22V reference when the output is forced to 20V. pin yields a minimum top resistor value of 2.6k. Figure 6. Reverse Output Current
1761 F06
current when the output is pulled above the input.
(LTC DWG # 05-08-1635) UPACKAGE DESCRIPTIO 1.50 – 1.75 (NOTE 4)2.80 BSC 0.30 – 0.45 TYP
5 PLCS (NOTE 3)
DATUM ‘A’ 0.09 – 0.20 (NOTE 3) S5 TSOT-23 0302 REV B PIN ONE
2.90 BSC
(NOTE 4)
0.95 BSC
1.90 BSC
0.80 – 0.90
1.00 MAX
0.01 – 0.100.20 BSC 0.30 – 0.50 REF NOTE: 1. DIMENSIONS ARE IN MILLIMETERS 2. DRAWING NOT TO SCALE 3. DIMENSIONS ARE INCLUSIVE OF PLATING 4. DIMENSIONS ARE EXCLUSIVE OF MOLD FLASH AND METAL BURR 5. MOLD FLASH SHALL NOT EXCEED 0.254mm 6. JEDEC PACKAGE REFERENCE IS MO-193
3.85 MAX
0.62 MAX 0.95 REF RECOMMENDED SOLDER PAD LAYOUT PER IPC CALCULATOR 1.4 MIN2.62 REF
1.22 REF
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 represen- tation that the interconnection of circuits as described herein will not infringe on existing patent rights.
LT 0507 REV C • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 2005 Linear Technology Corporation 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 ● FAX: (408) 434-0507 ● www.linear-tech.com RELATED PARTS PART NUMBER DESCRIPTION COMMENTS LT1120 125mA Low Dropout Regulator with 20 μA IQ Includes 2.5V Reference and Comparator LT1121 150mA Micropower Low Dropout Regulator 30 μA IQ, SOT-223 Package LT1129 700mA Micropower Low Dropout Regulator 50 μA Quiescent Current LT1175 500mA Negative Low Dropout Micropower Regulator 45 μA IQ, 0.26V Dropout Voltage, SOT-223 Package LT1521 300mA Low Dropout Micropower Regulator with Shutdown 15 μA IQ, Reverse Battery Protection LT1529 3A Low Dropout Regulator with 50 μA IQ 500mV Dropout Voltage LT1762 Series 150mA, Low Noise, LDO Micropower Regulator 25 μA Quiescent Current, 20μVRMS Noise LT1763 Series 500mA, Low Noise, LDO Micropower Regulator 30 μA Quiescent Current, 20μVRMS Noise LTC1928 Doubler Charge Pump with Low Noise Linear Regulator Low Output Noise: 60 μVRMS (100kHz BW) LT1962 Series 300mA, Low Noise, LDO Micropower Regulator 30 μA Quiescent Current, 20μVRMS Noise LT1963 1.5A, Low Noise, Fast Transient Response LDO 40 μVRMS, SOT-223 Package LT1764 3A, Low Noise, Fast Transient Response LDO 40 μVRMS, 340mV Dropout Voltage LTC3404 High Efficiency Synchronous Step-Down Switching Regulator Burst Mode TM Operation, Monolithic, 100% Duty Cycle Burst Mode is a trademark of Linear Technology Corporation.