Rad-hard 32-ch driver/decoder cuts board space in satellite applications

March 01, 2017 // By Graham Prophet
Intersil says its highly integrated ISL72813SEH can reduce command and telemetry design size by as much as 50%; the radiation hardened 32-channel driver is the first high current driver to integrate the decoder, level shifter and driver array in a single monolithic IC, allowing satellite manufacturers to significantly increase system capacity and reduce layout size.

The device offers a 4x higher density channel count compared to the nearest alternative, and the integrated level shifter eliminates several peripheral components. It uses Intersil’s own silicon on insulator (SOI) process, which provides single-event latch-up (SEL) robustness in heavy ion environments. The driver’s integrated decoder interfaces directly to the general purpose I/Os of FPGAs and CPUs in the satellite’s flight computer, reducing pin count compared to 1-input to 1-output driver arrays. Each of the device’s 32-channels of common-emitter open-collector driver outputs can generate pulses of up to 42V and 600 mA. The ISL72813SEH addresses latching relay and solenoid commanding for most satellite control functions, including redundancy management, mechanism drive enables, propulsion component relays and enables, battery management, and payload switch control. The ISL72813SEH’s low VCE saturation levels eliminate a major concern by reducing the overhead voltage required to drive the load. The driver’s power efficiency and high integration reduces the amount of circuitry required on the bus, allowing designers to add more spacecraft functionality and processing power.


Features and specifications of ISL72813SEH include;

• Acceptance tested to 50 krad(Si) LDR, wafer-by-wafer

• Integrated 5-bit to 32-channel decoder and level shifting circuit

• High collector current outputs to 600 mA

• Low VCE saturation of 1.5V with IC of 530 mA

• High voltage outputs up to -40V

• VCC supply range of 3V to 5.5V

• Extended operating temperature range of -55°C to +125°C

• HDR radiation tolerance of 100 krad(Si) and LDR of 50 krad(Si)

• SEB LETTH (VCE = 33V) immune up to 86.4 MeV•cm ²/mg


The ISL72813SEH can be combined with other Intersil ICs to create a complete satellite command and telemetry signal processing solution with superior rad hard performance. It comes in a 44-lead ceramic lead-less chip carrier (CLCC) package. An evaluation board is available to evaluate device features and performance. SEE and total dose testing reports also are available.