Overview
The STK672-440AN-E is a hybrid IC designed by Onsemi for use as a unipolar, 2-phase stepper motor driver with PWM current control. This component is tailored for applications requiring precise motor control and robust protection features. It is particularly suited for use in office equipment such as photocopiers and printers.
Key Specifications
| Parameter | Symbol | Conditions | Ratings | Unit |
|---|---|---|---|---|
| Maximum supply voltage 1 | Vcc max | No signal | 52 | V |
| Maximum supply voltage 2 | VDD max | No signal | -0.3 to 6.0 | V |
| Input voltage | Vin max | Logic input pins | -0.3 to 6.0 | V |
| Output current 1 | IOP max | 10μs 1 pulse (resistance load) | 10 | A |
| Output current 2 | IOH max | VDD = 5V, CLOCK ≥ 200Hz | 2.5 | A |
| Allowable power dissipation 1 | PdMF max | With an arbitrarily large heat sink. Per MOSFET | 7.3 | W |
| Allowable power dissipation 2 | PdPK max | No heat sink | 2.8 | W |
| Operating substrate temperature | Tcmax | 105 | °C | |
| Junction temperature | Tjmax | 150 | °C | |
| Storage temperature | Tstg | -40 to 125 | °C |
Key Features
- Built-in overcurrent detection function and overheat detection function with output current OFF.
- FAULT1 signal (active low) outputs when overcurrent or overheat is detected. FAULT2 signal outputs the result of protection circuit detection at two levels.
- Built-in power on reset function.
- Micro-step sine wave-driven driver can be activated by inputting an external clock.
- External pins can be used to select various excitation modes (2, 1-2, W1-2, 2W1-2, or 4W1-2 phase excitation).
- Rotational direction switching function.
- Schmitt input for 2.5V high level input.
- Incorporating a current detection resistor (0.152Ω: resistor tolerance ±2%) for motor current setting using two external resistors.
- ENABLE pin can cut output current while maintaining the excitation mode.
- Wide current setting range to reduce power consumption during standby.
- No motor sound is generated during hold mode due to external excitation current control.
- PWM operation is a separately excited system with constant current control that shifts the phase of Ach Bch.
- Compatible pins with STK672-430AN/-440AN/-442AN-E.
Applications
- Office photocopiers
- Printers
- Other office equipment requiring precise stepper motor control
Q & A
- What is the primary function of the STK672-440AN-E?
The STK672-440AN-E is a hybrid IC designed for use as a unipolar, 2-phase stepper motor driver with PWM current control.
- What are the key protection features of the STK672-440AN-E?
The IC includes built-in overcurrent detection and overheat detection functions, with FAULT1 and FAULT2 signals to indicate these conditions.
- How does the power on reset function work?
The power on reset function initializes internal IC operations when power is supplied, with a typical setting of 4V for power on reset.
- What excitation modes are supported by the STK672-440AN-E?
The IC supports various excitation modes including 2, 1-2, W1-2, 2W1-2, and 4W1-2 phase excitation.
- How is the rotational direction of the motor controlled?
The rotational direction can be switched using the CWB pin.
- What is the purpose of the ENABLE pin?
The ENABLE pin can be used to cut output current while maintaining the excitation mode.
- What are the allowable power dissipation limits for the STK672-440AN-E?
The allowable power dissipation is 7.3W per MOSFET with a large heat sink and 2.8W without a heat sink.
- What are the operating temperature limits for the STK672-440AN-E?
The operating substrate temperature limit is 105°C, and the junction temperature limit is 150°C.
- How is motor current set using the STK672-440AN-E?
Motor current can be set using two external resistors and a built-in current detection resistor (0.152Ω).
- What is the significance of the FAULT1 and FAULT2 signals?
FAULT1 outputs a low level when overcurrent or overheat is detected, while FAULT2 outputs the result of protection circuit detection at two levels.
