General description
The 33879 device is an 8-output hardware configurable, high-side/low-side switch
with 16-bit serial input control using the Serial Peripheral Interface (SPI). Two of the
outputs may be controlled directly via a microcontroller for pulse-width modulation
(PWM) applications. The 33879 incorporates SMARTMOS technology, with CMOS logic,
bipolar/MOS analog circuitry, and DMOS power MOSFETs. The 33879 controls various
inductive, incandescent, or LED loads by directly interfacing with a microcontroller. The
circuit’s innovative monitoring and protection features include very low standby currents,
cascade fault reporting, internal +45 V clamp voltage for low-side configuration, –20 V
high-side configuration, output specific diagnostics, and independent overtemperature
protection.

Features and benefits
• Designed to operate at 5.5 V < VPWR < 27.5 V
• 16-bit SPI for control and fault reporting, 3.3 V / 5.0 V compatible
• Outputs are current limited (0.6 A to 1.2 A) to drive incandescent lamps
• Output voltage clamp, + 45 V (low side) and –20 V (high side) during inductive
switching
• On/Off control of open load detect current (LED application)
• Internal reverse battery protection on VPWR
• Loss of ground or supply will not energize loads or damage IC
• Maximum 5.0 μA IPWR standby current at 13 V VPWR
• RDS(ON) of 0.75 Ω at 25 °C typical
• Short-circuit detect and current limit with automatic retry
• Independent overtemperature protection

Applications
• Solenoids
• Relays
• Actuators
• Stepper motors
• Brush DC motors
• Incandescent lamps