Overview
The AMIS-30421C4211RG, produced by onsemi, is a micro-stepping stepper motor bridge controller designed for large current range bipolar applications. This controller interfaces with an external microcontroller via a SPI interface to control two external power NMOS H-bridges. It features an on-chip voltage regulator, current sensing, a self-adapting PWM controller, and pre-drivers with smart slope control switching, ensuring EMC compliance suitable for industrial and automotive applications. The device is implemented in a mature technology, enabling fast high voltage analog circuitry and multiple digital functionalities on the same chip, making it ideal for use in automotive, industrial, medical, and marine environments.
Key Specifications
| Parameter | Min | Typ | Max | Unit | Remark/Test Conditions |
|---|---|---|---|---|---|
| VBB (Analog DC supply voltage) | 6 | - | 30 | V | Nominal operating supply range |
| VDD (Logic Supply Output Voltage) | 3.0 | - | 3.6 | V | Normal Mode |
| TJ (Junction temperature) | -40 | - | 125 | °C | - |
| fosc (Frequency of internal oscillator) | 6.4 | 8 | 9.6 | MHz | - |
| fPWM (PWM frequency) | 20 | 25 | 30 | kHz | Frequency depends only on internal oscillator |
| t1 (Bridge MOSFET switch on time) | 375 | 1250 | 4750 | ns | Selectable through SPI |
| toff (Bridge MOSFET switch off time) | 1250 | 4750 | - | ns | Selectable through SPI |
| ISLA (Load current on SLA-pin) | 0 | - | -40 | μA | - |
Key Features
- Dual H-Bridge Pre-Drivers for 2-Phase Stepper Motors
- Programmable Current via SPI
- On-chip Current Translator
- SPI Interface
- Speed and Load Angle Output
- 8 Step Modes from Full Step up to 64 Micro-Steps
- Current-Sense via Two External Sense Resistors
- PWM Current Control with Automatic Selection of Fast and Slow Decay
- Low EMC PWM with Selectable Voltage Slopes
- Full Output Protection and Diagnosis
- Thermal Warning and Shutdown
- Compatible with 3.3 V Microcontrollers
- Integrated 3.3 V Regulator to Supply External Microcontroller
- Integrated Reset Function to Reset External Microcontroller
- Pb-Free and RoHS Compliant
Applications
The AMIS-30421C4211RG is ideally suited for large current stepper motor applications in various industries, including:
- Automotive
- Industrial
- Medical
- Marine
Its robust design and features make it a reliable choice for demanding environments.
Q & A
- What is the primary function of the AMIS-30421C4211RG?
The AMIS-30421C4211RG is a micro-stepping stepper motor bridge controller designed to control two external power NMOS H-bridges for bipolar stepper motor applications.
- How does the AMIS-30421C4211RG interface with external controllers?
The device interfaces via a SPI interface with an external microcontroller.
- What are the key features of the PWM current control in the AMIS-30421C4211RG?
The PWM current control includes automatic selection of fast and slow decay, low EMC PWM with selectable voltage slopes, and a proprietary PWM algorithm for reliable current control.
- What is the purpose of the Speed and Load Angle output?
The Speed and Load Angle output allows for the creation of stall detection algorithms and control loops based on load angle to adjust torque and speed.
- What are the operating voltage ranges for VBB and VDD?
VBB operates from 6 to 30 V, and VDD operates from 3.0 to 3.6 V.
- What is the junction temperature range for the AMIS-30421C4211RG?
The junction temperature range is from -40 to 125 °C.
- Does the AMIS-30421C4211RG have thermal protection features?
Yes, it includes thermal warning and shutdown features.
- Is the AMIS-30421C4211RG compatible with 3.3 V microcontrollers?
Yes, it is compatible with 3.3 V microcontrollers and includes an integrated 3.3 V regulator to supply the external microcontroller.
- What are the step modes available on the AMIS-30421C4211RG?
The device supports 8 step modes from full step up to 64 micro-steps.
- Is the AMIS-30421C4211RG Pb-Free and RoHS compliant?
Yes, the device is Pb-Free and RoHS compliant.
