January 19, 2009

Sanken Develops SPI-6631M 3-Phase Brushless DC Motor Driver with 3 A Output Current
- Single-chip integration of pre-drive circuit and output elements saves at least 50% of the PCB area -

Sanken Electric Co., Ltd. announced today the development of the SPI-6631M, a new 3-phase brushless motor driver. The new driver features an output current of 3 A and integrates a pre-drive circuit and output elements on a single chip using a compact surface mounting package, saving at least 50% of the PCB area. Samples of the SPI-6631M are now being shipped at a price of 1,000 yen per unit (tax included), with mass-produced units scheduled to be available from April 2009. The SPI-6631M will initially be produced on a scale of 30,000 units/month, to be expanded to 100,000 units/month by April 2010.
1. Development Background and Product Overview
  Three-phase brushless DC motors driven on a low voltage and using power at a rate of around 50 W are currently employed in a wide variety of devices such as copier drums and washer/drier hot-air fans. The drivers of these motors are usually discretely configured by attaching a pre-drive circuit and output elements to a controller such as a microcontroller. However, as devices have become smaller and denser, demands have increased for the mounting area of motor drivers to be reduced—demands that have proven difficult to meet using discrete devices.

In response, Sanken has developed the SPI-6631M, a 3-phase brushless DC motor driver that saves at least 50% of the PCB area compared with drivers configured using discrete devices. This area reduction was achieved by integrating a pre-drive circuit and output elements (6 MOSFETs) on a single chip through the use of BCD process technology*, and by using a compact surface mounting package.

The SPI-6631M features an overcurrent protection circuit, overheat protection circuit, and undervoltage lockout protection circuit, as well as a function to report when these protection circuits are activated, contributing to higher equipment reliability.

The number of required components has also been reduced to less than one fifth through single-chip integration, considerably reducing the number of hours required for analyzing and controlling the components.
* Wafer process technology used for single-chip integration of bipolar technology, used to control analog circuits, CMOS technology, which allows fast operation and is ideal for digital controllers, and DMOS technology, which is ideal for large-current output.
2. Features
(1) Small surface mounting package
HSOP16 pin package (Resin dimensions: 12.2 × 7.5 × 2.5 mm)
(2) Sequence-free design
The SPI-6631M can be used without a sequencer for the power supply and for the signals input to the controller (CPU, etc.)
(3) Function to prevent high-side MOSFET and low-side MOSFET from being simultaneously on
High-side/low-side MOSFET short circuits do not occur even during microcontroller runaway or noise superimposition, preventing circuit malfunction and damage.
(4) Incorporation of various protection circuits outputting fail signals during operation
• Overcurrent protection circuit
• Overheat protection circuit
• Undervoltage lockout protection circuit
3. Applications
  Drum motors of copiers, drive motors of industrial robots, traveling motors of automatic vacuum cleaners, fan motors of washer/driers, etc.
4.  Specifications Overview
Parameter Symbol Rating Unit
Main power supply voltage VBB 13 to 33 V
Output current IO ±3.0 A
Output MOSFET on-resistance RDS(ON) 0.4 Ω
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