LTC3370_15 Datasheet, PDF (13/24 Pages) Linear Technology – 4-Channel 8A Configurable Buck DC/DCs

LTC3370
Pin Functions
RT (Pin 27): Oscillator Frequency Pin. This pin provides
two modes of setting the switching frequency. Connecting
a resistor from RT to ground sets the switching frequency
based on the resistor value. If RT is tied to V_CC the internal
2MHz oscillator is used. Do not float.
PLL/MODE (Pin 28): Oscillator Synchronization and Buck
Mode Select Pin. Driving PLL/MODE with an external clock
signal synchronizes all switches to the applied frequency,
and the buck converters operate in forced continuous
mode. The slope compensation is automatically adapted
to the external clock frequency. The absence of an external
clock signal enables the frequency programmed by the
RT pin. When not synchronizing to an external clock this
input determines how the LTC3370 operates at light loads.
Pulling this pin to ground selects Burst Mode operation.
Tying this pin to V_CC invokes forced continuous mode
operation. Do not float.
V_CC (Pin 29): Internal Bias Supply. Bypass to GND with a
10µF or larger ceramic capacitor.
TEMP (Pin 30): Temperature Indication Pin. TEMP outputs
a voltage of 220mV (typical) at 25°C. The TEMP voltage
increases by 7mV/°C (typical) at higher temperatures
giving an external indication of the LTC3370 internal die
temperature.
EN1 (Pin 31): Buck Regulator 1 Enable Input. Active high.
Do not float.
FB1 (Pin 32): Buck Regulator 1 Feedback Pin. Receives
feedback by a resistor divider connected across the output.
GND (Exposed Pad Pin 33): Ground. The exposed pad
should be connected to a continuous ground plane on the
printed circuit board directly under the LTC3370.
For more information www.linear.com/LTC3370
3370f
13