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DEVELOPMENT DATA
This data sheet contains advance information and specifications are subject to change without notice.
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7-81T ANALOGUE-TO-DIGITAL CONVERTER (ADC 7)
GENERAL DESCRIPTION
The PNA7509 is a monolithic NMOS 7-bit analogue-to-digital converter (AOC) designed for video applications. The device converts the analogue input signal into 7 -bit binary coded digital words at a sampling rate of 22 MHz.
The circuit comprises 129 comparators, a reference resistor chain, combining logic, transcoder stages, and TTL output buffers which are positive edge triggered and can be switched into 3-state mode. The digital output is selectable in two's complement or binary coding.
The use of separate outputs for overflow and underflow detection facilitates full-scale driving.