Datasheet LTC3873 (Analog Devices) - 5

LTC3873
TYPICAL PERFORMANCE CHARACTERISTICS Maximum Sense Threshold Frequency vs Temperature vs Temperature
250 300 IPRG = VIN 250 230 200 IPRG = FLOAT 210 150 190 IPRG = GND FREQUECY (kHz) 100 170 50 MAXIMUM SENSE THRESHOLD (mV) 150 0 –60 –40 –20 0 20 40 60 80 100 120 –60 –40 –20 0 20 40 60 80 100 120 TEMPERATURE (°C) TEMPERATURE (°C) 3873 G09 3873 G10
PIN FUNCTIONS (TS8/DDB) IPRG (Pin 1/Pin 4):
Current Sense Limit Select Pin.
RUN/SS (Pin 7/Pin 6):
Shutdown and External Soft-Start
I
Pin. In shutdown, all functions are disabled and the NGATE
TH (Pin 2/Pin 3):
This pin serves as the error amplifier compensation point. Nominal voltage range for this pin pin is held low. is 0.7V to 1.9V.
SW (Pin 8/Pin 5):
Switch node connection to inductor and
V
current sense input pin through external slope compensa-
FB (Pin 3/Pin 2):
This pin receives the feedback voltage from an external resistor divider across the output. tion resistor. Normally, the external N-channel MOSFET’s drain is connected to this pin.
GND (Pin 4/Pin 1):
Ground Pin.
Exposed Pad (NA/Pin 9):
Ground. Must be soldered to PCB
NGATE (Pin 5/Pin 8):
Gate Drive for the External N-Channel for electrical contact and rated thermal performance. MOSFET. This pin swings from 0V to VIN.
VCC (Pin 6/Pin 7):
Supply Pin. This pin must be closely decoupled to GND (Pin 4). 3873fb For more information www.linear.com/LTC3873 5