TERADYNE Tester Board CY7C291A-35WMB

The CY7C291A-35WMB is not a circuit board for a Teradyne test system; rather, it is a military-grade, UV-erasable PROM memory chip manufactured by Cypress (now part of Infineon). While it may be used within Teradyne test equipment to store firmware or calibration data, it is a general-purpose electronic component, not a proprietary board designed exclusively for such systems.

Key Specifications

The chip features a 2K × 8-bit organization and an access time of 35ns. It comes in a 24-pin windowed CerDIP package and supports reprogramming after being erased via ultraviolet light. It is rated for a military-grade operating temperature range of -55°C to +125°C, operates on a 5V supply, and has a maximum operating current of 90mA. It requires a 12.5V programming voltage and features three-state output control.

Role in Test Equipment

In ATE (Automated Test Equipment) systems—such as those from Teradyne—PROMs of this type are typically used to store device firmware, calibration coefficients, or configuration parameters. Its military-grade temperature rating and the reliability afforded by its ceramic package align with the requirements for long-term, stable operation in test equipment. As this model has been discontinued, sourcing it for the repair of legacy equipment may require checking authorized channels—such as Rochester Electronics—or the secondary market.