ATA6386 Atmel's New Hex Half-bridge Driver IC in BCD-on-SOI Technology Cuts Car Comfort-application Costs

In contrast to standard BCDMOS bulk technology, Atmel's innovative SMARTIS technology uses an SOI (Silicon-On-Insulator) substrate. Due to the SOI technology's dielectric isolation, junction leakage, a major issue in high-temperature designs, is minimized. Furthermore, SOI devices provide superior latch-up immunity leading to increased circuit reliability.

The ATA6836 is a fully protected hex half-bridge driver with integrated power stages. Each of the six high-side and low-side drivers is capable of driving currents up to 650 mA via a microcontroller, e.g., Atmel's automotive-qualified microcontroller ATmega88. Customers' assembly efforts are substantially reduced as external clamping diodes are not needed due to the half-bridge configuration.

One of the main applications of the ATA6836 is the actuation of three fully independent DC motors in three H-bridges. The ATA6836 also supports the operation of up to five DC motors sharing four common lines, as long as the motors are not all actuated at the same time. This configuration can be used, for example, in automotive air conditioning systems, where five air-flow control flaps can be operated from one ATA6836. Software can be used to avoid the simultaneous actuation of the DC motors. In addition, the half-bridge configuration also enables the operation of six different resistive or inductive loads.

The ATA6836 provides several protection features such as overtemperature warning and shutdown, overload, overvoltage protection, and full protection against short-circuits. The SPI output register contains a number of diagnostic bits, which can be read by the microcontroller. In the event of undervoltage at the supply pin, the power-supply fail bit in the output register is set and all outputs are disabled. If the overtemperature pre-warning bit is set, software routines to decrease the power dissipation and temperature can be implemented. Temperature increases beyond a certain level can force the IC to shut down to prevent destruction.

The ATA6836 features 4 kV ESD protection, which provides maximum safety against damage during assembly. The device also meets the strict automotive qualification demands (protection against conducted interference, EMC, and ESD protection) and can withstand transients as specified in ISO/TR 7637.

Availability and Pricing

Samples of the ATA6836 driver IC are available now in Pb-free QFN24 packages, measuring only 5 mm x 5 mm. Customers using the predecessor version, T6816, can easily switch to the SO28 package to accommodate new designs. For applications with more powerful DC motors, Atmel offers the high-power version ATA6838 with 1.5A output stages. All other features are identical to the ATA6836. Pricing starts at US $2.00 for the ATA6836 and at US $2.10 for the ATA6838 for 10k-piece quantities each. An application board for development support can be ordered for US $130.

Footnote

BCDMOS = Mixed-signal technology with Bipolar, CMOS and DMOS components

DC = Direct Current

EMC = Electro Magnetic Compatibility

ESD = Electronic Static Discharge

QFN = Quad Flat No Leads

SOI = Silicon On Insulator technology

SPI = Serial Peripheral Interface