Datasheet LT3956 (Analog Devices) - 3
| Hersteller | Analog Devices |
| Beschreibung | 80VIN, 80VOUT Constant-Current, Constant-Voltage Converter |
| Seiten / Seite | 20 / 3 — The. denotes the specifications which apply over the full operating temp- |
| Dateiformat / Größe | PDF / 1.5 Mb |
| Dokumentensprache | Englisch |
The. denotes the specifications which apply over the full operating temp-
Modelllinie für dieses Datenblatt
Textversion des Dokuments
LT3956 e lecTrical characTerisTics
The
l
denotes the specifications which apply over the full operating temp- erature range, otherwise specifications are at TA = 25°C. VIN = 24V, EN/UVLO = 24V, CTRL = 2V, PWM = 5V, unless otherwise noted. PARAMETER CONDITIONS MIN TYP MAX UNITS
SW Pin Leakage SW = 48V 5 10 µA SW Pin Current Limit l 3.3 3.9 4.6 A SW Pin Voltage Drop I(SW) = 2A 220 mV SS Pull-Up Current Current Out of Pin 8 10 13 µA
Error Amplifier
Full-Scale Current Sense Threshold ( V(ISP–ISN)) FB = 0V, ISP = 48V, CTRL ≥ 1.2V l 240 250 257 mV Current Sense Threshold at CTRL = 1V ( V(ISP–ISN)) CTRL = 1V, FB = 0V, ISP = 48V l 217 225 231 mV Current Sense Threshold at CTRL = 0.5V ( V(ISP–ISN)) CTRL = 0.5V l 96 100 103 mV Current Sense Threshold at CTRL = 0.1V ( V(ISP–ISN)) CTRL = 0.1V, FB = 0V, ISP = 48V l –2.5 0 4.5 mV CTRL Range for Current Sense Threshold Adjustment 0 1.1 V CTRL Input Bias Current Current Out of Pin, CTRL = 0V 50 100 nA Current Sense Amplifier Input Common Mode 2.9 80 V Range ( VISN) ISP/ISN Short-Circuit Threshold ( V(ISP–ISN)) ISN = 0V 300 335 370 mV ISP/ISN Short-Circuit Fault Sensing Common Mode 0 3 V Range ( VISN) ISP/ISN Input Bias Current (Combined) PWM = 5V (Active), ISP = ISN = 48V 80 µA PWM = 0V (Standby), ISP = ISN = 48V 0 0.1 µA LED Current Sense Amplifier gm 120 µS VC Output Impedance 1V < VC < 2V 15000 kΩ VC Standby Input Bias Current PWM = 0V –20 20 nA FB Regulation Voltage (VFB) ISP = ISN = 0V, 48V l 1.220 1.250 1.270 V 1.232 1.250 1.265 V FB Amplifier gm FB = VFB, ISP = ISN 480 µS FB Pin Input Bias Current Current Out of Pin, FB = 1V 40 100 nA FB Voltage Loop Active Threshold VMODE Falling VFB – VFB – VFB – V 65mV 50mV 40mV FB Overvoltage Threshold PWMOUT Falling VFB + 50mV VFB + VFB + V 60mV 80mV
Oscillator
Switching Frequency RT = 100k l 90 100 125 kHz RT = 10k 925 1000 1050 kHz SW Minimum Off-Time 170 ns SW Minimum On-Time 200 ns
Linear Regulator
INTVCC Regulation Voltage 7 7.15 7.3 V Dropout (VIN – INTVCC) IINTVCC = –10mA, VIN = 7V 1 V INTVCC Undervoltage Lockout l 4.1 4.4 V INTVCC Current Limit 14 17 25 mA INTVCC Current in Shutdown EN/UVLO = 0V, INTVCC = 7V 8 12 µA 3956f Document Outline Features Description Applications Typical Application Absolute Maximum Ratings Pin Configuration order information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Application Package Description Typical Application Related Parts
The
l
denotes the specifications which apply over the full operating temp- erature range, otherwise specifications are at TA = 25°C. VIN = 24V, EN/UVLO = 24V, CTRL = 2V, PWM = 5V, unless otherwise noted. PARAMETER CONDITIONS MIN TYP MAX UNITS
SW Pin Leakage SW = 48V 5 10 µA SW Pin Current Limit l 3.3 3.9 4.6 A SW Pin Voltage Drop I(SW) = 2A 220 mV SS Pull-Up Current Current Out of Pin 8 10 13 µA
Error Amplifier
Full-Scale Current Sense Threshold ( V(ISP–ISN)) FB = 0V, ISP = 48V, CTRL ≥ 1.2V l 240 250 257 mV Current Sense Threshold at CTRL = 1V ( V(ISP–ISN)) CTRL = 1V, FB = 0V, ISP = 48V l 217 225 231 mV Current Sense Threshold at CTRL = 0.5V ( V(ISP–ISN)) CTRL = 0.5V l 96 100 103 mV Current Sense Threshold at CTRL = 0.1V ( V(ISP–ISN)) CTRL = 0.1V, FB = 0V, ISP = 48V l –2.5 0 4.5 mV CTRL Range for Current Sense Threshold Adjustment 0 1.1 V CTRL Input Bias Current Current Out of Pin, CTRL = 0V 50 100 nA Current Sense Amplifier Input Common Mode 2.9 80 V Range ( VISN) ISP/ISN Short-Circuit Threshold ( V(ISP–ISN)) ISN = 0V 300 335 370 mV ISP/ISN Short-Circuit Fault Sensing Common Mode 0 3 V Range ( VISN) ISP/ISN Input Bias Current (Combined) PWM = 5V (Active), ISP = ISN = 48V 80 µA PWM = 0V (Standby), ISP = ISN = 48V 0 0.1 µA LED Current Sense Amplifier gm 120 µS VC Output Impedance 1V < VC < 2V 15000 kΩ VC Standby Input Bias Current PWM = 0V –20 20 nA FB Regulation Voltage (VFB) ISP = ISN = 0V, 48V l 1.220 1.250 1.270 V 1.232 1.250 1.265 V FB Amplifier gm FB = VFB, ISP = ISN 480 µS FB Pin Input Bias Current Current Out of Pin, FB = 1V 40 100 nA FB Voltage Loop Active Threshold VMODE Falling VFB – VFB – VFB – V 65mV 50mV 40mV FB Overvoltage Threshold PWMOUT Falling VFB + 50mV VFB + VFB + V 60mV 80mV
Oscillator
Switching Frequency RT = 100k l 90 100 125 kHz RT = 10k 925 1000 1050 kHz SW Minimum Off-Time 170 ns SW Minimum On-Time 200 ns
Linear Regulator
INTVCC Regulation Voltage 7 7.15 7.3 V Dropout (VIN – INTVCC) IINTVCC = –10mA, VIN = 7V 1 V INTVCC Undervoltage Lockout l 4.1 4.4 V INTVCC Current Limit 14 17 25 mA INTVCC Current in Shutdown EN/UVLO = 0V, INTVCC = 7V 8 12 µA 3956f Document Outline Features Description Applications Typical Application Absolute Maximum Ratings Pin Configuration order information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Application Package Description Typical Application Related Parts