LTC3827 Datasheet, PDF (9/36 Pages) Linear Technology – Low IQ, Dual, 2-Phase Synchronous Step-Down Controller

LTC3827
PIN FUNCTIONS
TRACK/SS1, TRACK/SS2 (Pins 29, 13): External Track-
ing and Soft-Start Input. The LTC3827 regulates the
V_FB1,2 voltage to the smaller of 0.8V or the voltage on the
TRACK/SS1,2 pin. A internal 1μA pull-up current source
is connected to this pin. A capacitor to ground at this
pin sets the ramp time to final regulated output voltage.
Alternatively, a resistor divider on another voltage supply
connected to this pin allows the LTC3827 output to track
the other supply during startup.
I_TH1, I_TH2 (Pins 30, 12): Error Amplifier Outputs and
Switching Regulator Compensation Points. Each associ-
ated channel’s current comparator trip point increases
with this control voltage.
V_FB1, V_FB2 (Pins 31, 11): Receives the remotely sensed
feedback voltage for each controller from an external
resistive divider across the output.
SENSE1⁺, SENSE2⁺ (Pins 32, 10): The (+) Input to the
Differential Current Comparators. The I_TH pin voltage and
controlled offsets between the SENSE^– and SENSE⁺ pins in
conjunction with R_SENSE set the current trip threshold.
Exposed Pad (Pin 33): SGND. Must be soldered to the
PCB.
3827ff
9