General Description 

The ADC0801, ADC0802, ADC0803, ADC0804 and ADC0805 are CMOS 8-bit successive approximation A/D converters that use a differential potentiometric ladderÐ similar to the 256R products. These converters are designed to allow operation with the NSC800 and INS8080A derivative control bus with TRI-STATEÉ output latches directly driving the data bus. These A/Ds appear like memory locations or I/O ports to the microprocessor and no interfacing logic is needed. Differential analog voltage inputs allow increasing the common-mode rejection and offsetting the analog zero input voltage value. In addition, the voltage reference input can be adjusted to allow encoding any smaller analog voltage span to the full 8 bits of resolution. 

Features 

Y Compatible with 8080 mP derivativesÐno interfacing logic needed - access time - 135 ns Y Easy interface to all microprocessors, or operates ‘‘stand alone’’ Y Differential analog voltage inputs Y Logic inputs and outputs meet both MOS and TTL voltage level specifications Y Works with 2.5V (LM336) voltage reference Y On-chip clock generator Y 0V to 5V analog input voltage range with single 5V supply Y No zero adjust required Y 0.3× standard width 20-pin DIP package Y 20-pin molded chip carrier or small outline package Y Operates ratiometrically or with 5 VDC, 2.5 VDC, or analog span adjusted voltage reference Key Specifications Y Resolution 8 bits Y Total error g(/4 LSB, g(/2 LSB and g1 LSB Y Conversion time 100 ms