8-bit addressable latch with Schmitt-trigger inputs
The Texas Instruments SN74HCS259DR is an 8-bit addressable latch from the 74HCS logic family, combining a 1:8 demultiplexer and a storage latch in a single 16-SOIC package. It accepts a D-type input and routes it to one of eight outputs based on a three-bit address, with the remaining outputs held in their previous state. The tri-state outputs allow direct connection to shared data buses without external buffers. The -40°C to 125°C operating temperature range qualifies it for industrial and automotive under-hood environments — outdoor telecom cabinets, factory-floor I/O modules, and engine-adjacent ECUs. The 16-SOIC package (3.90 mm width) fits standard PCB layouts and is compatible with automated assembly.
6 ns propagation delay — timing margin on the bus
At 6 ns typical propagation delay, the SN74HCS259DR adds minimal latency to the address-to-data path. In a typical address-decoding application where the latch sits between the microcontroller address bus and a memory chip, the 6 ns delay leaves headroom for the memory's own access time and board-level trace delays. No need to derate bus speed for this part unless the system clock exceeds roughly 40 MHz.
Tri-state outputs and bus sharing
Tri-state outputs let the latch release the bus when not selected.
Active production — no LTB risk
ROHS3 compliant, lead-free, and suitable for new designs.