Abstract: An implantable medical device telemetry system provides a means for decoding telemetry downlink information transmitted from an external unit to an implanted medical device, and for encoding telemetry uplink signals to be transmitted from the implanted device to the external unit. A novel system architecture results in a very small telemetry subsystem in the implanted device and a very flexible system adaptable to be used in conjunction with various telemetry formats of various implanted devices. A programmable logic array (PLA) structure that is mask programmable and which may further be partially RAM programmable serves as the basis of the telemetry subsystem. For downlink telemetry, a counter is enabled during intervals of interest in the downlink RF burst stream. The counter value at the end of such an interval is then applied to the variable inputs of the PLA tier decoding in accordance with a selected telemetry protocol.