A Monolithic (Single-Chip) Video A/D Converter

A monolithic video A/D converter has been developed that offers reduced size and power, improved reliability, a wider operating temperature range, and lower cost than has been previously possible. The fully-parallel “flash” method of conversion is used, taking advantage of the close matching of components and tight control of propagation delays characteristic in monolithic circuits. Eight bit performance is achieved at video bandwidths without a sample-and-hold circuit. Application of the part requires only a −2-V reference and a buffer amplifier capable of driving the 255 parallel comparator inputs, a load similar to that of a 75ω cable. The circuit is fully TTL compatible and is controlled by a single convert signal. Provisions are made to invert the MSB for two's complement coding, or inverting the entire output field, if desired. Two converters can be used in a feed-forward configuration to convert 14 bits. The 64 pin dual in-line package reflects a conservative thermal design, allowing the circuit to operate to specification over the 0 to 70°C ambient temperature range in still air. Device characterization has demonstrated extreme stability over time and temperature. Accelerated life testing predicts a mean-time-to-failure at 125°C of greater than 1.1 × 10⁶ hours (125 years).

Print ISSN

0036-1682

Published

1980-08

Content type

Original Research

DOI

10.5594/J01584