Rad-hard 16-channel current driver with integrated decoder

The device allows satellite manufacturers to significantly increase system capacity and cut solution footprint by 50% for their medium Earth orbit (MEO), geosynchronous Earth orbit (GEO), highly elliptical orbit (HEO), and deep space mission profiles. 

Multiple ISL72814SEH current drivers are able to send 28V/500mA pulses for 750ms to the more than 1,500 RF switches in a communication satellite’s payload, routing RF signals to the designated Internet radio stations and television channels. They also send 12 to 30V with 50 to 600mA latching pulses to control the relays and solenoids that turn on/off the propulsion system thrusters, change orbital altitude, and turn on the motor to tilt the solar panels.

The ISL72814SEH offers twice the channel count and 54% less VCE(SAT) power dissipation on each channel compared to competitive drivers. Its integrated level shifter removes several peripheral components, and its internal clamp diodes eliminate the need for additional protection circuitry when driving inductive loads. 

The ISL72814SEH leverages Renesas’ proprietary silicon on insulator process to provide single-event effects (SEE) robustness in heavy ion environments. The driver’s integrated decoder interfaces directly to the general purpose I/Os of FPGAs and microprocessors in the satellite’s flight computer, dramatically reducing pin count compared to 1-input to 1-output driver arrays.

Each of the ISL72814SEH’s 16-channels of common-collector open-emitter PNP driver outputs can generate pulses of up to 42V and 700mA. The device is wafer acceptance tested to 100krad(Si) over high dose rate (HDR), and 75krad(Si) over low dose rate (LDR) total dose testing.

Characterisation testing is completed with no single event latch-up (SEL), single event burnout (SEB), and single event transients (SETs) at a linear energy transfer (LET) of up to 86MeV*cm2/mg.

“The ISL72814SEH offers satellite customers the ultimate in radiation immunity, mass and power savings,” said Philip Chesley, Vice President, Industrial Analog and Power Business Division, Renesas Electronics Corporation. “Our current driver significantly reduces the circuitry required on the bus, enabling manufacturers to add more functionality and processing power to their next generation satellites.” 

Features of the ISL72814SEH:

• Integrated four-bit to 16-channel decoder and input level shifter.
• High current outputs up to 700mA.
• High voltage outputs up to 42V.
• VCC supply range of three to 13.2V.
• Ultra-low VCE saturation of 1.35V at 500mA.
• Extended operating temperature range of -55 to +125°C.

The ISL72814SEH can be combined with the following ICs to create a satellite command and telemetry signal processing solution with superior rad-hard performance: ISL71590SEH temperature sensor, ISL70591SEH precision current source, ISL71840SEH 30V 16-channel multiplexer, ISL70517SEH 36V differential input in-amp, ISL70419SEH precision op amp, ISL71090SEH12 precision voltage reference, and ISL72026BSEH CAN transceiver.

The ISL72814SEH radiation-hardened 16-channel current driver is available now in a 28-lead ceramic flatpack package. An evaluation board is available to evaluate device features and performance.