New Industry Products

Gate Driver and Power MOSFET Solutions for BLDC Control

May 22, 2017 by Jeff Shepard

Texas Instruments (TI) today introduced two new device families that help reduce size and weight in motor drive applications. When used together, DRV832x brushless DC (BLDC) gate drivers and CSD88584/99 NexFET™ Power Blocks require as little as 511 mm², half the board space of competing solutions.

The DRV832x BLDC gate drivers feature a smart gate-drive architecture that eliminates up to 24 components traditionally used to set the gate drive current while enabling designers to easily adjust field-effect transistor (FET) switching to optimize power loss and electromagnetic compliance. The CSD88584Q5DC and CSD88599Q5DC power blocks leverage two FETs in a unique stacked-die configuration, which doubles power density and minimizes the FET resistance and parasitic inductances typically found in side-by-side FET configurations.

An 18-Volt compact BLDC motor reference design demonstrates how the DRV8323 gate driver and CSD88584Q5DC power block can drive 11W/cm3 power and enable engineers to jump-start their designs for smaller, lighter-weight power tools, integrated motor modules, drones and more.

Benefits of using a CSD88584/99 and DRV832x device together: The combined solution delivers 700W of motor power without a heat sink, providing 50 percent higher current than conventional solutions without increasing the footprint. As demonstrated by the 18-Volt BLDC reference design, the smart gate driver and power block are capable of driving a peak current of up to 160A for more than 1 second. The combination enables shorter trace lengths and actively prevents unintended FET turn-on, while also providing undervoltage, overcurrent and thermal protection.

The CSD88584Q5DC and CSD88599Q5DC power blocks come in TI's DualCoolâ„¢ thermally enhanced package, which enables designers to apply a heat sink to the top of the device to decrease thermal impedance and increase the amount of power dissipated to maintain safe operating temperatures for the board and end application. The power blocks' switch-node clip helps eliminate parasitic inductance between high- and low-side FETs. Additionally, the DRV832x gate driver's passive component integration minimizes board traces.

In addition to the 18-Volt BLDC motor reference design, engineers can search for other motor reference designs that use the power blocks and gate drivers to help solve their system design challenges. The three-phase smart gate-driver evaluation module (EVM) allows designers to drive a 15-A, three-phase BLDC motor using the DRV8323R gate driver, CSD88599Q5DC power block and MSP430F5529 microcontroller LaunchPadâ„¢ development kit. The EVM is available from the TI store for US$99.00.

The new DRV832x BLDC smart gate drivers offer peripheral and interface options for engineers to select the best device for their design: with or without an integrated buck regulator or three integrated current-shunt amplifiers. Each device option is available in a hardware or serial interface and comes in quad flat no-lead (QFN) packaging. The CSD88584/99 power blocks come in DualCool small outline no-lead (SON) packaging, with 40- or 60-V breakdown voltage (BVDSS) choices.

Currently-available devices along with key features include (pricing is in lots of 1,000): DRV8320 smart gate drive in a 5mm x 5mm package, $1.41; DRV8320R integrated buck regulator in a 6mm x 6mm package, $2.01; DRV8323 integrated current shunt amplifiers in a 6mm x 6mm package, $1.60; DRV8323R integrated buck regulator and current-shunt amplifiers in a 7mm x 7mm package, $2.19; CSD88584Q5DC 40-V BVDSS, 0.68-mΩ typical on-resistance in a 5mm x 6mm package, $2.24; and the CSD88599Q5DC 60-V BVDSS, 1.7-mΩ typical on-resistance in a 5mm x 6mm package, $2.50.