
PIN FUNCTIONS
N.
Name
N.C.
Function
1, 2, 9, 11, 12, 15,
16, 17, 18, 24, 25,
31, 32, 33, 34, 44,
47, 48, 49, 50, 56,
57, 63, 64
3, 4, 13, 14
26, 27
54, 55
5
Not Connected.
OUT B
OUT C
OUT A
MUX_SGL
The outputs of the three DMOS half bridge drivers.
Logic input used to configure BEMF output tobe multiplexed (high) or a single
output (low).
Ground.
Power supply for internal circuitry. 5V power supply must beconnected directly
to pin.
Used as time reference for internalperiod and mask counters.
Output for BEMF comparator.
Input for center tap of motor.
5V power supply for the DMOS drivers. Series Schottky diode may be used in
applications where BEMF voltage must be used for head parking.
Input for motor current control voltage.
A capacitor and resistor are connected to this pin for external compensation of
the transconductance loop.
Input for connection of a resistor for configuration of the output slew rate during
commutation.
Pin for connection of RSENSE, an external resistor used to sense the motor
current
Pin for connection of capacitor to ground for the internal step up converter.
Pin for connection of inductor to V
DD
for the internal step up converter.
External capacitor to ground which stores energy for useduring braking.
Active LOW logic input that turns off all drivers, and triggers the delayed brake.
Pin for connection of external RC network to configure delay of braking.
Logic input to configure the gain in the current sense feedback loop (K). Low
state produces gain of 4, high state produces a gain of 16.
Rising edge triggered input used to increment the commutationsequencer.
Logic input used in conjunction with CLOCK. For CLOCK = Low and RESET =
high the sequencer is forced to state 1. For CLOCK = high and RESET = high
an immediate BRAKE is initiated. An immediate BRAKE implies no delay.
6, 7, 8, 39, 40, 41, 42
10
GND
V
DD
19
20
21
FREF
BEMF
CTAP
VP
22, 23, 45, 46
28
29
V
IN
COMP
30
SLEW
35, 36, 37, 58, 59
SENSE
38
43
51
52
53
60
CBOOST
LBOOST
PD_CAP
BRK
BRK_DLY
GAIN
61
62
CLOCK
RESET
L6237
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