ADC0854

Features:

* 2 or 4 channel multiplexer
* Differential or Single-ended input, software controlled
* Serial digital data interface
* 256 programmable reference voltage levels
*  Continuous comparison after programming
* Fixed, ratiometric, or reduced span reference capability
    (ADC 0854)


Pinout




Specifications

Current into Va (Note 3) ...................................................15 mA
Supply Voltage, VCC (Note 3) ..............................................6.5V
Voltage
Logic and Analog Inputs................................ -0.3V to VCC a0.3V
Input Current per Pin......................................................  ± 5mA
Input Current per Package ........................................... ± 20 mA
Storage Temperature .......................................-65 to +150
Package Dissipation
at TA e 25 (Board Mount) .................................................0.8W
Lead Temp. (Soldering, 10 seconds)
Dual-In-Line Package (plastic) ............................................260
ESD Susceptibility (Note 14) ...............................................2000V


Description

The ADC0852 and ADC0854 are CMOS devices that combine a versatile analog input multiplexer, voltage compara- tor, and an 8-bit DAC which provides the comparator's threshold voltage (VTH). The comparator provides a ''1-bit'' output as a result of a comparison between the analog input and the DAC's output. This allows for easy implementation of set-point, on-off or ''bang-bang'' control systems with several advantages over previous devices.

The ADC0854 has a 4 input multiplexer that can be software configured for single ended, pseudo-differential, and full-differential modes of operation. In addition the DAC's reference input is brought out to allow for reduction of the span. The ADC0852 has a two input multiplexer that can be configured as 2 single-ended or 1 differential input pair. The DAC reference input is internally tied to VCC.

The ADC0852 and ADC0854 multiplexer and 8-bit DAC are programmed via a serial data input word. Once programmed the output is updated once each clock cycle up to a maximum clock rate of 400 kHz.