Datasheet LTC3806 (Analog Devices) - 6

LTC3806
U U U PI FU CTIO S RUN (Pin 1):
The RUN pin provides the user with an
INTVCC (Pin 6):
The Internal 6.9V Regulator Output. The accurate means for sensing the input voltage and pro- gate drivers and control circuits are powered from this gramming the start-up threshold for the converter. The voltage. Decouple this pin locally to the IC ground with a falling RUN pin threshold is nominally 1.14V and the minimum 4.7μF low ESR ceramic capacitor. comparator has 91mV of hysteresis for noise immunity.
GND (Pins 7, 13):
Ground Pins. Exposed pad must be tied When the RUN pin is below this input threshold, the gate to electrical ground. drive outputs G1 and G2 are held low. The absolute maximum rating for the voltage on this pin is 7V.
G2 (Pin 8):
Secondary-Side Gate Driver Output. This pin drives the gates of all of the synchronous rectifiers.
ITH (Pin 2):
Error Amplifier Compensation Pin. The current comparator input threshold increases with this control
G1 (Pin 9):
Primary-Side Gate Driver Output. voltage. Nominal voltage range for this pin is 0V to 1.4V.
SS (Pin 10):
Soft-Start. A capacitor between this pin and
FB (Pin 3):
Receives the feedback voltage from the exter- ground sets the rate at which the current comparator input nal resistor divider across the main output. Nominal threshold may increase when the IC is initially enabled. voltage for this pin in regulation is 1.230V. Increasing the size of the capacitor slows down the ramp rate and reduces the inrush current.
NC (Pins 4, 11):
Do Not Connect.
SENSE (Pin 12):
Current Sense Input for the Control Loop.
VIN (Pin 5):
Main Supply Pin. Must be closely decoupled Connect this pin to the current sense resistor in the source to ground. of the primary side power MOSFET. Internal leading edge blanking is provided. 3806fb 6