Datasheet LT3952A (Analog Devices) - 3

LT3952A
ELECTRICAL CHARACTERISTICS The
l
denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VIN = IVINP = IVINN = 12V, ISP = ISN = 24V, EN/UVLO = PWM = 3V, CTRL = 2V, OVLO = 0V unless otherwise noted PARAMETER CONDITIONS MIN TYP MAX UNITS
Minimum Operating Voltage 3 V Supply Current FB = 1.3V, RT = 40.2k, CTRL = 0V 1.5 2.2 mA EN/UVLO = 0V, CTRL = 0V 0 1 µA EN/UVLO = 1.15V, CTRL = 0V 35 60 µA
Internal Regulator
INTVCC Output Voltage CTRL = 0V 2.90 3.00 3.10 V INTVCC Dropout Voltage VIN = 3V, CTRL = 0V 150 mV INTVCC Undervoltage Lockout INTVCC Rising, CTRL = 0V 2.62 2.68 2.74 V INTVCC UVLO Hysteresis CTRL = 0V 200 mV
Reference Voltage Output
VREF Voltage IVREF = –100μA , CTRL = 0V l 1.955 2.000 2.045 V VREF Line Regulation 3V < VIN < 42V , CTRL = 0V 0.01 %/V VREF Load Regulation 0µA < IVREF < –100µA , CTRL = 0V 0.6 %
Current Feedback
CTRL Range for Current Sense Threshold Adjustment 0.2 1.2 V CTRL PWM Shutdown Threshold CTRL Falling 100 125 mV CTRL PWM Threshold Hysteresis 12.5 mV CTRL Zero-Scale Offset 200 mV CTRL Input Bias Current CTRL = 0V, Current Out of Pin 20 100 nA Current Sense Common Mode Input Range CTRL = 1.5V 0 60 V Full-Scale Current Sense Accuracy (VISP-VISN) ISP = 60V, CTRL = 1.5V l 245 250 255 mV Midrange Current Sense Accuracy (VISP-VISN) ISP = 60V, CTRL = 0.7V 115 125 135 mV 1/10th Scale Current Sense Accuracy (VISP-VISN) ISP = 60V, CTRL = 0.3V 10 25 40 mV Low Side Current Sense Accuracy (VISP-VISN) ISP = 0V, CTRL = 1.5V l 243 250 257 mV Overcurrent Sense Threshold l 350 375 390 mV ISP to VC Transconductance CTRL = 1.5V 275 µS ISP/ISN Input Bias Current PWM = 5V (Active), ISP = 60V 250 µA PWM = 0V (Standby), ISP = 60V 12 20 µA Current Sense Monitor Ratio (VISMON)/(VISP-VISN) CTRL = 0.4V, 0.8V 4 V/V Current Sense Monitor Accuracy (VISMON) CTRL = 1.5V , ISP = 60V 0.950 1.000 1.050 V
Input Current Sense Amplifier
Amplifier Supply Current (From IVINP) IVINP = IVINN = 42V 35 60 µA IVIN Regulation Threshold (VIVINP-IVINN) l 57 60 63 mV IVINCOMP to VC Transconductance 1650 µS Input Common Mode Minimum Voltage 3 V IVINP/IVINN to Monitor Voltage Gain 20 V/V Rev A For more information www.analog.com 3 Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Order Information Pin Configuration Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Package Description Revision History Typical Application Related Parts