New serial-in, parallel-out device combines cold-sparing support, internal triple redundancy, and an output latch for unidirectional I/O expansion and redundant logic architectures
PLANO, Texas, September 10, 2026 – Apogee Semiconductor today announced the AP54RHC5942, a radiation-hardened-by-design 8-bit serial-in, parallel-out shift register with latched outputs. Designed for commercial space and other applications demanding radiation tolerance and high reliability, the device allows a simple serial bus to control multiple logic outputs while supporting cascaded expansion and redundant cold-sparing configurations.
The AP54RHC5942 is fabricated in 180 nm CMOS process using proprietary radiation-hardening techniques. Its triple-redundant design extends throughout the circuitry, providing immunity to single-event transients without requiring additional redundant devices. A proprietary output stage, input and output protection circuitry, and an internal power-on reset support cold sparing with no static power penalty on any device pad.
“The AP54RHC5942 gives system designers an efficient way to expand logic outputs while preserving the redundancy and cold-sparing behavior required in high-reliability architectures,” said Mark Hamlyn, General Manager, Apogee Semiconductor. “Its serial interface, latched outputs, and internal triple redundancy are designed to simplify implementation across a range of control applications.”
Supporting Expandable and Redundant Logic Architectures
Multiple AP54RHC5942 devices can be cascaded while sharing CLK and LATCH signals, with DATA_OUT from one device feeding DATA_IN on the next. The application example in the datasheet shows two cascaded devices creating 16 logic outputs from three microprocessor pins to sequentially enable 16 separate PMIC devices.
For fully redundant designs, AP54RHC family functions can be placed in parallel on separate power supplies. The family’s cold-sparing I/O architecture is designed to allow direct parallel connections without unwanted leakage-current paths when one path is powered down. If a supply or function fails, a system can power down that path and enable the redundant path without additional input or output switching or configuration changes.
Key Features
- 1.4V to 5.5V operation
- Inputs tolerant up to 5.5V at any VCC
- Provides logic-level down translation to VCC
- Extended operating temperature range (-55 °C to +125 °C)
- Cold sparing capability with no static power penalty
- Built-in triple redundancy for enhanced reliability
- Power-on reset (POR) ensures reliable power up and power down in hot plug and cold sparing operations
- 30 krad (Si) TID resilience at 5.5 V
- SEL immune to LET of 75 MeV-cm2 /mg
- Meets NASA’s ASTM E595 outgassing specification
- Moisture sensitivity level : MSL 1
Ordering and Availability
Contact Apogee for flight grade orders and current lead-time confirmation: orders@apogeesemi.com | +1 9725594660.
About Apogee Semiconductor
Apogee Semiconductor is a leading provider of radiation-hardened semiconductor solutions for space, aerospace, and defense applications. The company develops high-performance microelectronics designed to withstand extreme environments, enabling mission-critical systems in the most challenging conditions.
