
ON Semiconductor
Overview
The STK672-440A-E is a hybrid IC for use as a unipolar, 2-phase stepping motor driver with PWM current control.
Features
• Built-in overcurrent detection function (output current OFF).
• Built-in overheat detection function (output current OFF).
• If either over-current or overheat detection function is activated,
the FAULT1 signal (active low) is output.
The FAULT2 signal is used to output the result of activation of
protection circuit detection at 2 levels.
• Built-in power on reset function.
• A micro-step sine wave-driven driver can be activated merely by inputting an external clock.
• External pins can be used to select 2, 1-2 (including pseudo-micro),
W1-2, 2 W1-2, or 4W1-2 excitation.
• The switch timing of the 4-phase distributor can be switched
by setting an external pin (MODE3) to detect either the
rise and fall, or rise only, of CLOCK input.
• Phase is maintained even when the excitation mode is switched.
Rotational direction switching function.
• Supports schmitt input for 2.5V high level input.
• Incorporating a current detection resistor (0.122Ω: resistor tolerance ±2%),
motor current can be set using two external resistors.
• The ENABLE pin can be used to cut output current while maintaining the excitation mode.
• With a wide current setting range, power consumption can be reduced during standby.
• No motor sound is generated during hold mode due to external excitation current control.
• A external excitation system is used for PWM operations.
Fixed current control for shifting the phase of Ach/Bch is
used for the PWM phase.
Applications
• Office photocopiers, printers, etc.