R297XX

• Devices are available in military (-55°C to +125°C) temperature range
• Standard PROMs are offered in power-switched SPROM versions
• Typically, 75% power savings achieved by deselected SPROMs
• Reliable nichrome fuses
• Three-state outputs
• Devices programmed on standard PROM programmers
• High immunity or resistance to space levels of radiation
• Device pinouts comply with JEDEC standards
• Available in surface mount and through-hole packaging
• PROMs and SPROMs are offered in 24-pin, 0.3" wide DIPs

Fairchild Semiconductor Electronics Semiconductor Division's Bipolar Field Programmable Read-Only Memories R297XX include both standard and power-switched versions. CS/PS inputs provide logic flexibility and ease of memory expansion decoding. SPROM power-switch circuitry is activated by the PS input.

Fairchild Semiconductor PROMs and SPROMs are manufactured with nichrome fuses and low power Schottky technology. The devices are shipped with all bits in the HIGH (logical ONE) state. To achieve a LOW state in a given bit location the nichrome link is fused open by passing a short, high current pulse through the link. All devices are programmed using the same programming technique.

Standard PROMs are enabled by a single active LOW CS or by both active LOW CS and HIGH CS inputs. Powerswitched PROMs (SPROMs) are enabled by a single active LOW PS or by both active LOW PS and HIGH PS inputs. See the individual block diagrams for the enable scheme.