BRUSHLESS DC MOTOR CONTROLLER
FSP33035
PIN DESCRIPTION
Pin Number
Pin Name
Pin Function
1, 2, 24
These three open collector Top Drive outputs are designed to drive
the external upper power switch transistors.
BT , AT , CT
3
Fwd/Rev
The Forward/Reverse Input is used to change the direction of motor
rotation.
4, 5, 6
7
These three Sensor Inputs control the commutation sequence.
SA, SB, SC
Output Enable
A logic high at this input causes the motor to run, while a low causes it to
coast.
8
9
Reference Output
This output provides charging current for the oscillator timing capacitor CT
and a reference for the error amplifier. It may also serve to furnish sensor
power.
Current Sense
Noninverting Input
A 100 mV signal, with respect to Pin 15, at this input terminates output
switch conduction during a given oscillator cycle. This pin normally
connects to the top side of the current sense resistor.
10
11
12
13
14
Oscillator
The Oscillator frequency is programmed by the values selected for the
timing components, RT and CT.
This input is normally connected to the speed set potentiometer.
Error Amp
Noninverting Input
Error Amp
Inverting Input
This input is normally connected to the Error Amp Output in open loop
applications.
This pin is available for compensation in closed loop applications.
Error Amp
Out/PWM Input
Fault Output
This open collector output is active low during one or more of the following
conditions: Invalid Sensor Input code, Enable Input at logic 0, Current
Sense Input greater than 100 mV (Pin 9 with respect to Pin 15),
Undervoltage Lockout activation, and Thermal Shutdown.
Current Sense
Inverting Input
Reference pin for internal 100 mV threshold. This pin is normally
connected to the bottom side of the current sense resistor.
15
16
17
18
Gnd
VCC
VC
This pin supplies a ground for the control circuit and should be referenced
back to the power source ground.
This pin is the positive supply of the control IC. The controller is functional
over a minimum VCC range of 10 to 30 V.
The high state (VOH) of the Bottom Drive Outputs is set by the voltage
applied to this pin. The controller is operational over a minimum VC range
of 10 to 30 V.
19, 20, 21
22
These three totem pole Bottom Drive Outputs are designed for direct drive
of the external bottom power switch transistors.
CB, BB, AB
60°/120 ° Select
The electrical state of this pin configures the control circuit operation for
either 60° (high state) or 120°(low state) sensor electrical phasing inputs.
23
Brake
A logic low state at this input allows the motor to run, while a high state
does not allow motor operation and if operating causes rapid deceleration.
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2007-3-16
FOSLINK [ FOSLINK SEMICONDUCTOR CO.,LTD ]
