25-09-2010, 05:11 PM
ADC0804.pdf (Size: 1.1 MB / Downloads: 42)
General Description
Abstract
The ADC0801, ADC0802, ADC0803, ADC0804 and ADC0805 are CMOS 8-bit successive approximation A/D converters that use a differential potentiometric ladder—similar to the 256R products. These converters are designed to allow operation with the NSC800 and INS8080A derivative control bus with TRI-STATE 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
Compatible with 8080
μP derivatives—no interfacing logic needed - access time - 135 ns n Easy interface to all microprocessors, or operates “stand alone” Differential analog voltage inputs n Logic inputs and outputs meet both MOS and TTL voltage level specifications Works with 2.5V (LM336) voltage reference
On-chip clock generator 0V to 5V analog input voltage range with single 5V supply
No zero adjust required 0.3" standard width 20-pin DIP package
20-pin molded chip carrier or small outline package
Operates ratiometrically or with 5 VDC, 2.5 VDC, or analog span adjusted voltage reference Key Specifications n Resolution 8 bits
Total error ±1⁄4 LSB, ±1⁄2 LSB and ±1 LSB n Conversion time 100 μs