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FAN5032 Rev. 1.0.0

9

VRHOT

VR Hot Output. Open drain output that goes high when the TTSENSE voltage goes

below the internal VRHOT threshold.

10

TTSENSE

Thermal Sense Input. A positive internal current source is connected to this pin.

Connecting an external NTC thermistor between this pin and GND produces a positive

input voltage that is proportional to temperature.

11

ILIMIT

Current Limit Set. An external resistor from this pin to GND sets the current limit

threshold of the converter.

12

RT

Frequency Set Input. An external resistor connected between this pin and GND sets

the oscillator frequency of the device.

13

RAMPADJ

PWM Ramp Set Input. An external resistor connected between this pin and the

converter input voltage sets the internal PWM ramp.

14

LLSET

Load Line Set Input. This pin can be directly connected to CSCOMP or connected to

the center point of a resistor divider between CSCOMP and CSREF. Connecting LLSET

to CSREF disables positioning.

15

CSREF

Current Sense Amplifier Positive Input. The voltage on this pin is used as the

reference for the current sense amplifier. The power good and crowbar functions are

also internally connected to this pin.

16

CSSUM

Current Sense Amplifier Negative Input

17

CSCOMP

Current Sense Amplifier Compensation Output

18

GND

Ground. All internal biasing and logic output signals of the device are referenced to this

ground.

19

OD

Output Disable. This pin is actively pulled low when the EN input is low or when VCC is

below its UVLO threshold, to disable the external MOSFET drivers.

20 to 21 NC

No Connection

22 to 25 SW4 to SW1

Switching Node Current Balance Inputs. Sense the switching side of the inductor and

are used to measure the current level in each phase. The SW pins of unused phases

should be left open.

26

NC

No Connection

27 to 30 PWM4 to PWM1 PWM Outputs. Each output is connected to the input of an external MOSFET driver,

such as the FAN5109. Connecting the PWM3 and/or PWM4 outputs to VCC disables

that phase, allowing the FAN5032 to operate as a 2, 3, or 4 phase controller.

31

VCC

Supply Voltage for the Device

32 to 39 VID7 to VID0

Voltage Identification Code Inputs. These digital inputs are connected to the internal

DAC and are used to program the output voltage. These pins have 1µA internal pull-

down; left open, the input state is decoded as logic low.

40

VIDSEL

VID Table Select Input. A logic low selects the extended VR10 DAC table and a logic

high selects the VR11 DAC table. This pin has a 1µA internal pull-down; left open, the

input state is decoded as logic low.

–

Exposed Paddle Internally connected to die ground. May be connected to ground or left floating.

Connect to ground for lowest package thermal resistance.

Pin #

Pin Name

Pin Description