Datasheet LTC3803-5 (Analog Devices) - 6
| Manufacturer | Analog Devices |
| Description | Constant Frequency Current Mode Flyback DC/DC Controller in ThinSOT |
| Pages / Page | 16 / 6 — PIN FUNCTIONS. ITH/RUN (Pin 1):. SENSE (Pin 4):. VCC (Pin 5):. GND (Pin … |
| File Format / Size | PDF / 171 Kb |
| Document Language | English |
PIN FUNCTIONS. ITH/RUN (Pin 1):. SENSE (Pin 4):. VCC (Pin 5):. GND (Pin 2):. VFB (Pin 3):. NGATE (Pin 6):. BLOCK DIAGRAM
Model Line for this Datasheet
Text Version of Document
LTC3803-5
PIN FUNCTIONS ITH/RUN (Pin 1):
This pin performs two functions. It
SENSE (Pin 4):
This pin performs two functions. It monitors serves as the error amplifi er compensation point as well switch current by reading the voltage across an external as the run/shutdown control input. Nominal voltage range current sense resistor to ground. It also injects a current is 0.7V to 1.9V. Forcing this pin below the shutdown ramp that develops slope compensation voltage across threshold (VITHSHDN) causes the LTC3803-5 to shut down. an optional external programming resistor. In shutdown mode, the NGATE pin is held low.
VCC (Pin 5):
Supply Pin. Must be closely decoupled to
GND (Pin 2):
Ground Pin. GND (Pin 2).
VFB (Pin 3):
Receives the feedback voltage from an external
NGATE (Pin 6):
Gate Drive for the External N-channel resistive divider across the output. MOSFET. This pin swings from 0V to VCC.
BLOCK DIAGRAM
5 VCC SHUTDOWN COMPARATOR 0.3μA 0.28V + VCC < VTURNON V UNDERVOLTAGE CC SHUNT LOCKOUT 800mV REGULATOR – REFERENCE SHUTDOWN SOFT- START CLAMP CURRENT – COMPARATOR VCC ERROR + AMPLIFIER GATE SWITCHING R DRIVER + NGATE LOGIC AND Q 6 V BLANKING FB 3 – S CIRCUIT SLOPE COMP 20mV GND 200kHz 1.2V CURRENT 2 OSCILLATOR RAMP SENSE 4 ITH/RUN 1 38035 BD 38035fd 6 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 APPLICATIONS PACKAGE DESCRIPTION REVISION HISTORY TYPICAL APPLICATION RELATED PARTS
PIN FUNCTIONS ITH/RUN (Pin 1):
This pin performs two functions. It
SENSE (Pin 4):
This pin performs two functions. It monitors serves as the error amplifi er compensation point as well switch current by reading the voltage across an external as the run/shutdown control input. Nominal voltage range current sense resistor to ground. It also injects a current is 0.7V to 1.9V. Forcing this pin below the shutdown ramp that develops slope compensation voltage across threshold (VITHSHDN) causes the LTC3803-5 to shut down. an optional external programming resistor. In shutdown mode, the NGATE pin is held low.
VCC (Pin 5):
Supply Pin. Must be closely decoupled to
GND (Pin 2):
Ground Pin. GND (Pin 2).
VFB (Pin 3):
Receives the feedback voltage from an external
NGATE (Pin 6):
Gate Drive for the External N-channel resistive divider across the output. MOSFET. This pin swings from 0V to VCC.
BLOCK DIAGRAM
5 VCC SHUTDOWN COMPARATOR 0.3μA 0.28V + VCC < VTURNON V UNDERVOLTAGE CC SHUNT LOCKOUT 800mV REGULATOR – REFERENCE SHUTDOWN SOFT- START CLAMP CURRENT – COMPARATOR VCC ERROR + AMPLIFIER GATE SWITCHING R DRIVER + NGATE LOGIC AND Q 6 V BLANKING FB 3 – S CIRCUIT SLOPE COMP 20mV GND 200kHz 1.2V CURRENT 2 OSCILLATOR RAMP SENSE 4 ITH/RUN 1 38035 BD 38035fd 6 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 APPLICATIONS PACKAGE DESCRIPTION REVISION HISTORY TYPICAL APPLICATION RELATED PARTS
