STK672-632AN-E Datasheet, PDF (7/28 Pages) ON Semiconductor – 2-phase Stepper Motor Driver

STK672-632AN-E
[Setting the motor current]
The motor current, IOH, is set using the Pin 19 voltage, Vref, of the hybrid IC.
Equations related to IOH and Vref are given below.
Vref  (RO2  (RO2+RO1))VDD(5V) ··········································· (1)
IOH  (Vref  4.9)  Rs ······························································· (2)
The value of 4.9 in Equation (2) above represents the Vref voltage as divided by a circuit inside the control IC.
Rs : 0.141 (Current detection resistor inside the hybrid IC)
IOH
0
[Smoke Emission Precuations]
If Pin 18 (S.G terminal) is attached to the board without using solder, overcurrent may flow into the MOSFET at VCCON
(24V ON), causing the STK672-632AN-E to emit smoke because 5V circuits cannot be controlled.
In addition, as long as one of the output Pins, 1, 3, 4, or 5, is open, inductance energy stored in the motor results in
electrical stress on the driver, possibly resulting in the emission of smoke.
Input Pin Functions
Pin Name
CLOCK
Pin No.
12
MODE1
10
MODE2
17
CWB
13
RESETB
14
ENABLE
15
Function
Reference clock for motor phase current switching
Excitation mode selection
Motor direction switching
System reset
Initial state of A and BB phase excitation in the timing charts
is set by switching from low to high.
The A, AB, B, and BB outputs are turned off, and after
operation is restored by returning the ENABLE pin to the
high level, operation continues with the same excitation
timing as before the low-level input.
Input Conditions When Operating
Operates on the rising edge of the signal (MODE2=H)
Low: 2-phase excitation
High: 1-2 phase excitation
High: Rising edge
Low: Rising and falling edge
Low: CW (forward)
High: CCW (reverse)
A reset is applied by a low level
The A, AB, B, and BB outputs are turned off by a
low-level input.
Output Pin Functions
Pin Name
Pin No.
Function
FAULT
Monitor pin used when over-current detection or overheat
16
detection function is activated.
Note : See the timing chart for the concrete details on circuit operation.
Input Conditions When Operating
Low level is output when detected.
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