KF7020
AEC-Q100 qualified dual H-bridge driver with 3A peak current for DC motors and stepper motors
Product Overview
Description
The KF7020 is a dual H-bridge motor driver capable of driving two DC motors or one stepper motor. It features AEC-Q100 qualification for automotive applications with integrated power MOSFETs and protection features.
This driver supports motor supply voltages from 2.5V to 14V with 3A peak current per bridge. The low Rds(on) of 200mΩ ensures efficient operation with minimal heat generation.
Built-in protection features include over-current protection, thermal shutdown, and under-voltage lockout. The KF7020 is suitable for mirror adjustment, seat control, and HVAC damper applications.
Product Series
KF
Primary Application
Mirror adjustment
Key Features
- AEC-Q100 qualified
- Dual H-bridge configuration
- Low Rds(on) integrated MOSFETs
- 3A peak current capability
- Current regulation and limiting
- Thermal shutdown protection
Specifications
| Motor Supply Voltage | 2.5V-14V |
|---|---|
| Logic Supply Voltage | 2.5V-5.5V |
| Peak Current | 3A per bridge |
| Continuous Current | 1.5A per bridge |
| Rds(on) | 200mΩ (typ) |
| Control Interface | Logic/PWM |
| Temperature Range | -40°C to +125°C |
| Package | HTSSOP-24 |
Applications
Mirror adjustment
Electronic system design
Seat control modules
Industrial automation and control
HVAC dampers
Electronic system design
Window lift
Renewable energy systems
Sunroof control
Industrial automation and control
FAE Expert Insights
"The KF7020 is a versatile dual H-bridge driver suitable for a wide range of automotive motor applications. The integrated MOSFETs with 200mΩ Rds(on) provide good efficiency for battery-powered applications. In my experience, this driver works well for mirror adjustment, seat control, and HVAC applications. The 3A peak current capability handles motor startup and stall conditions adequately. I appreciate the simple control interface - just logic inputs for direction and PWM for speed control. The current regulation feature is useful for limiting stall current and protecting the motor. For applications requiring higher current, consider the KF7030 which offers 5A capability."
Versatile dual H-bridge driver ideal for automotive body electronics motors
— Alex Zhou, BeiLuo
Frequently Asked Questions
What is the difference between peak and continuous current ratings?
Peak current rating is the maximum current the driver can handle for short durations (typically milliseconds), while continuous current rating is the sustained current under normal operating conditions. The KF7020 is rated for 3A peak and 1.5A continuous per bridge. Peak current capability is important for motor startup (inrush current can be 3-5x running current) and stall conditions. Continuous rating determines the maximum normal operating current. Always design for continuous rating with thermal margin, using peak rating only for transient conditions.
Design for continuous current rating. Use peak rating for startup and transient conditions only.
How do I control motor speed with KF7020?
Motor speed control with KF7020 uses PWM (Pulse Width Modulation). Set direction inputs (IN1, IN2) for forward or reverse rotation, then apply PWM signal to enable input for speed control. PWM frequency typically ranges from 1-20kHz (above audible range). Duty cycle determines speed - 0% stopped, 100% full speed. The KF7020 internal drivers handle the PWM switching of the H-bridge. Ensure PWM frequency is not too high to avoid excessive switching losses while maintaining smooth motor operation.
Use 10-20kHz PWM frequency for speed control. Contact LiTong for motor control design guidance.
What is back-EMF and how do I protect against it?
Back-EMF (electromotive force) is voltage generated by the motor when it acts as a generator during deceleration or when power is removed. The back-EMF can exceed supply voltage and damage the driver. Protection methods include internal diodes (most drivers have body diodes that conduct back-EMF), external Schottky diodes across motor terminals, TVS diodes to clamp voltage spikes, and capacitors to absorb energy from small motors. The KF7020 has internal protection, but external Schottky diodes are recommended for large motors or harsh conditions.
Add external Schottky diodes for large motors or critical applications. Contact LiTong for protection design guidance.
Can KF7020 drive stepper motors?
Yes, the KF7020 can drive bipolar stepper motors using both H-bridges. Connect one bridge to each phase of the stepper motor. Control requires proper sequencing of the four inputs to create rotating magnetic field. For full-step operation, use the sequence: AB-AB'-A'B'-A'B. For half-step, interleave with single-phase steps. However, dedicated stepper drivers like KF8020 offer better microstepping performance and current control for precision applications.
Use KF7020 for basic stepper control. For precision applications, consider KF8020 stepper driver. Contact LiTong for stepper motor solutions.
How do I calculate power dissipation in motor drivers?
Motor driver power dissipation calculation: P = I² × Rds(on) × 2 (for two conducting MOSFETs in H-bridge). For example, with 1A motor current and 200mΩ Rds(on): P = 1² × 0.2 × 2 = 0.4W. Add switching losses if PWM is used. Calculate junction temperature: Tj = Ta + (P × Rthja). Ensure Tj stays below maximum rating (typically 125°C or 150°C). For high-current or high-temperature applications, consider thermal management or higher-current drivers.
Calculate thermal performance for your operating conditions. Contact LiTong for thermal design support.