BP6308
Dual H-bridge motor driver with 2.5A peak current for DC motor and stepper motor applications
Product Overview
Description
The BP6308 is a dual H-bridge motor driver capable of driving two DC motors or one stepper motor. It features integrated power MOSFETs with low Rds(on) for high efficiency and minimal heat generation.
This driver supports motor supply voltages from 2.5V to 14V and provides up to 2.5A peak current per bridge. The internal current regulation and over-current protection ensure reliable operation under various load conditions.
Built-in protection features include over-current protection, thermal shutdown, and under-voltage lockout. The BP6308 is controlled through simple logic inputs or PWM signals for speed control.
Product Series
BP
Primary Application
Toys and robotics
Key Features
- Dual H-bridge configuration
- Low Rds(on) integrated MOSFETs
- 2.5A peak current capability
- Current regulation and limiting
- Thermal shutdown protection
- Simple logic/PWM control
Specifications
| Motor Supply Voltage | 2.5V-14V |
|---|---|
| Logic Supply Voltage | 2.5V-5.5V |
| Peak Current | 2.5A per bridge |
| Continuous Current | 1.5A per bridge |
| Rds(on) | 280mΩ (typ) |
| Control Interface | Logic/PWM |
| Package | SSOP-24 |
Applications
Toys and robotics
Electronic system design
Battery-powered tools
Battery and charging management
Printers and scanners
Electronic system design
Small appliances
Electronic system design
Camera autofocus
Electronic system design
FAE Expert Insights
"The BP6308 is a versatile dual H-bridge driver suitable for a wide range of small motor applications. The integrated MOSFETs with 280mΩ Rds(on) provide good efficiency for battery-powered applications. In my experience, this driver works well for toy motors, small robotics, and consumer electronics. The 2.5A 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 BP6310 which offers 4A capability. The SSOP-24 package provides good thermal performance for the power level."
Versatile dual H-bridge driver ideal for small DC motors and battery-powered applications
— 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 BP6308 is rated for 2.5A 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 BP6308?
Motor speed control with BP6308 uses PWM (Pulse Width Modulation): 1) Set direction inputs (IN1, IN2) for forward or reverse rotation, 2) Apply PWM signal to enable input for speed control, 3) PWM frequency typically 1-20kHz (above audible range), 4) Duty cycle determines speed - 0% stopped, 100% full speed, 5) Use microcontroller PWM output or external PWM generator. The BP6308 internal drivers handle the PWM switching of the H-bridge. Ensure PWM frequency is not too high to avoid excessive switching losses.
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: 1) Internal diodes - most drivers have body diodes that conduct back-EMF, 2) External Schottky diodes - add fast diodes across motor terminals, 3) TVS diodes - clamp voltage spikes to safe levels, 4) Capacitors - absorb energy from small motors. The BP6308 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 BP6308 drive stepper motors?
Yes, the BP6308 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 (IN1, IN2 for phase A; IN3, IN4 for phase B) 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. For microstepping, use PWM current control. However, dedicated stepper drivers like BP6601 offer better microstepping performance and current control for precision applications.
Use BP6308 for basic stepper control. For precision applications, consider dedicated stepper drivers. 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 280mΩ Rds(on): P = 1² × 0.28 × 2 = 0.56W. Add switching losses if PWM is used: Psw = 0.5 × V × I × (tr + tf) × fsw. 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.