Pin Description
Pin
1
Pin Name
Vcc5V
Pin Function
Supply Voltage Input (5V nominal)
2
Divsel
Selects Phase Mode. Logic low selects 4 phase. Logic high selects 3 phase. 2 phase
operation is achieved by using 2 outputs in 4 phase mode.
3
4
Clksel
Extclk
Clock Select: Logic high selects internal clock. Logic low selects external clock.
=
External Clock Input. Output frequency Clock Input / No. of Phases. Connect to Vcc5V to
select internal clock.
5
Rref
Connects to external reference resistor. Sets the operating frequency of the internal clock
and the ramp time for the PWM. Reference voltage at this pin is 1.26V.
6
7
Vid0
Vid1
Vid2
Vid3
Vid4
OC+
OC−
COMP
5-Bit DAC Input (LSB).
5-Bit DAC Input.
8
5-Bit DAC Input.
9
5-Bit DAC Input.
10
11
12
13
5-Bit DAC Input (MSB)
Over-current Comparator. Non-inverting input.
Over-current Comparator. Inverting input.
Compensation Pin. This is the output of the internal transconductance amplifier.
Compensation network should be connected between this pin and feedback ground FBG.
14
15
FB
Feedback Input. Normally Kelvin connected to supply output.
Bgout
Current Limit Flag. Goes to logic low when current limit is activated. When over-current
condition is removed, this pin is weakly pulled up to Vcc5V.
16
17
18
19
20
21
22
23
24
FBG
Feedback Ground. This pin should be connected to the ground at the supply output.
ENABLE
GND
Output Enable Pin. Tie to logic high to enable and logic low to disable.
Power Ground Pin.
DRV2
DRV0
Vcc12V
DRV1
DRV3
OutV
Phase 2 Output.
Phase 0 Output.
Supply Voltage for FET Drivers DRV0:3.
Phase 1 Output.
Phase 3 Output.
Sets the maximum DRV0:3 drive voltage to reduce switching loss in external FET’s.
5
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