Datasheet LT3957A (Analog Devices) - 4
| Manufacturer | Analog Devices |
| Description | Boost, Flyback, SEPIC and Inverting Converter with 5A, 40V Switch |
| Pages / Page | 28 / 4 — ELECTRICAL CHARACTERISTICS. The. denotes the specifications which apply … |
| File Format / Size | PDF / 567 Kb |
| Document Language | English |
ELECTRICAL CHARACTERISTICS. The. denotes the specifications which apply over the full operating temp-
Model Line for this Datasheet
Text Version of Document
LT3957A
ELECTRICAL CHARACTERISTICS The
l
denotes the specifications which apply over the full operating temp- erature range, otherwise specifications are at TA ≈ TJ = 25°C. VIN = 24V, EN/UVLO = 24V, SENSE2 = 0V, unless otherwise noted. PARAMETER CONDITIONS MIN TYP MAX UNITS
INTVCC Current Limit VIN = 40V 32 40 55 mA VIN = 15V 95 mA INTVCC Load Regulation (ΔVINTVCC / VINTVCC) 0 < IINTVCC < 20mA, VIN = 8V –1 –0.5 % INTVCC Line Regulation (ΔVINTVCC / [ΔVIN • VINTVCC]) 6V < VIN < 40V 0.02 0.05 %/V Dropout Voltage (VIN – VINTVCC) VIN = 5V, IINTVCC = 20mA, VC = 0V 450 mV INTVCC Current in Shutdown EN/UVLO = 0V, INTVCC = 6V 17 μA INTVCC Voltage to Bypass Internal LDO 5.5 V
Logic Inputs
EN/UVLO Threshold Voltage Falling VIN = INTVCC = 6V l 1.17 1.22 1.27 V EN/UVLO Voltage Hysteresis 20 mV EN/UVLO Input Low Voltage IVIN Drops Below 1μA 0.4 V EN/UVLO Pin Bias Current Low EN/UVLO = 1.15V 1.7 2 2.5 μA EN/UVLO Pin Bias Current High EN/UVLO = 1.33V 20 100 nA
Note 1:
Stresses beyond those listed under Absolute Maximum Ratings
Note 3:
The LT3957A is tested in a feedback loop which servos VFBX to the may cause permanent damage to the device. Exposure to any Absolute reference voltages (1.6V and –0.8V) with the VC pin forced to 1.3V. Maximum Rating condition for extended periods may affect device
Note 4:
FBX overvoltage lockout is measured at VFBX(OVERVOLTAGE) relative reliability and lifetime. to regulated VFBX(REG).
Note 2:
The LT3957AE is guaranteed to meet performance specifications
Note 5:
For 3V ≤ VIN < 6V, the EN/UVLO pin must not exceed VIN. from the 0°C to 125°C operating junction temperature. Specifications over
Note 6:
EN/UVLO = 1.33V when VIN = 3V. the –40°C to 125°C operating junction temperature range are assured by design, characterization and correlation with statistical process controls. The LT3957AI is guaranteed over the full –40°C to 125°C operating junction temperature range.
TYPICAL PERFORMANCE CHARACTERISTICS TA ≈ TJ = 25°C, unless otherwise noted. Positive Feedback Voltage Negative Feedback Voltage Quiescent Current vs Temperature, VIN vs Temperature, VIN vs Temperature, VIN
1605 –788 1.8 –790 VIN = INTVCC = 3V VIN = 40V SHDN/UVLO = 1.33V 1600 VIN = 24V –792 1.7 VIN = 40V –794 V V IN = 8V IN = 24V V 1590 IN = 8V –796 1.6 –798 V V 1585 IN = INTVCC = 3V, VIN = 40V IN = INTVCC = 3V SHDN –800 /UVLO = 1.33V VIN = 24V QUIESCENT CURRENT (mA) 1.5 –802 REGULATED FEEDBACK VOLTAGE (mV) REGULATED FEEDBACK VOLTAGE (mV) 1580 –804 1.4 –50 –25 0 25 50 75 100 125 –50 –25 0 25 50 75 100 125 –50 –25 0 25 50 75 100 125 TEMPERATURE (°C) TEMPERATURE (°C) TEMPERATURE (°C) 3957A G01 3957A G02 3957A G03 3957afa 4
ELECTRICAL CHARACTERISTICS The
l
denotes the specifications which apply over the full operating temp- erature range, otherwise specifications are at TA ≈ TJ = 25°C. VIN = 24V, EN/UVLO = 24V, SENSE2 = 0V, unless otherwise noted. PARAMETER CONDITIONS MIN TYP MAX UNITS
INTVCC Current Limit VIN = 40V 32 40 55 mA VIN = 15V 95 mA INTVCC Load Regulation (ΔVINTVCC / VINTVCC) 0 < IINTVCC < 20mA, VIN = 8V –1 –0.5 % INTVCC Line Regulation (ΔVINTVCC / [ΔVIN • VINTVCC]) 6V < VIN < 40V 0.02 0.05 %/V Dropout Voltage (VIN – VINTVCC) VIN = 5V, IINTVCC = 20mA, VC = 0V 450 mV INTVCC Current in Shutdown EN/UVLO = 0V, INTVCC = 6V 17 μA INTVCC Voltage to Bypass Internal LDO 5.5 V
Logic Inputs
EN/UVLO Threshold Voltage Falling VIN = INTVCC = 6V l 1.17 1.22 1.27 V EN/UVLO Voltage Hysteresis 20 mV EN/UVLO Input Low Voltage IVIN Drops Below 1μA 0.4 V EN/UVLO Pin Bias Current Low EN/UVLO = 1.15V 1.7 2 2.5 μA EN/UVLO Pin Bias Current High EN/UVLO = 1.33V 20 100 nA
Note 1:
Stresses beyond those listed under Absolute Maximum Ratings
Note 3:
The LT3957A is tested in a feedback loop which servos VFBX to the may cause permanent damage to the device. Exposure to any Absolute reference voltages (1.6V and –0.8V) with the VC pin forced to 1.3V. Maximum Rating condition for extended periods may affect device
Note 4:
FBX overvoltage lockout is measured at VFBX(OVERVOLTAGE) relative reliability and lifetime. to regulated VFBX(REG).
Note 2:
The LT3957AE is guaranteed to meet performance specifications
Note 5:
For 3V ≤ VIN < 6V, the EN/UVLO pin must not exceed VIN. from the 0°C to 125°C operating junction temperature. Specifications over
Note 6:
EN/UVLO = 1.33V when VIN = 3V. the –40°C to 125°C operating junction temperature range are assured by design, characterization and correlation with statistical process controls. The LT3957AI is guaranteed over the full –40°C to 125°C operating junction temperature range.
TYPICAL PERFORMANCE CHARACTERISTICS TA ≈ TJ = 25°C, unless otherwise noted. Positive Feedback Voltage Negative Feedback Voltage Quiescent Current vs Temperature, VIN vs Temperature, VIN vs Temperature, VIN
1605 –788 1.8 –790 VIN = INTVCC = 3V VIN = 40V SHDN/UVLO = 1.33V 1600 VIN = 24V –792 1.7 VIN = 40V –794 V V IN = 8V IN = 24V V 1590 IN = 8V –796 1.6 –798 V V 1585 IN = INTVCC = 3V, VIN = 40V IN = INTVCC = 3V SHDN –800 /UVLO = 1.33V VIN = 24V QUIESCENT CURRENT (mA) 1.5 –802 REGULATED FEEDBACK VOLTAGE (mV) REGULATED FEEDBACK VOLTAGE (mV) 1580 –804 1.4 –50 –25 0 25 50 75 100 125 –50 –25 0 25 50 75 100 125 –50 –25 0 25 50 75 100 125 TEMPERATURE (°C) TEMPERATURE (°C) TEMPERATURE (°C) 3957A G01 3957A G02 3957A G03 3957afa 4
