3½ Digit LCD, Low Power Display, A/D
Converter with Overrange Recovery
Features
•First Reading Overrange Recovery in One Conversion Period
•Guaranteed Zero Reading for 0V Input on All Scales
•True Polarity at Zero for Precise Null Detection
•1pA Typical Input Current
•True Differential Input and Reference, Direct Display Drive
-LCD ICL7136
•Low Noise - Less Than 15µVP-P
•On Chip Clock and Reference
•No Additional Active Circuits Required
•Low Power - Less Than 1mW
•Surface Mount Package Available
•Drop-In Replacement for ICL7126, No Changes Needed
•Pb-Free Plus Anneal Available (RoHS Compliant)

The Intersil ICL7136 is a high performance, low power 3½
digit, A/D converter. Included are seven segment decoders,
display drivers, a reference, and a clock. The ICL7136 is
designed to interface with a liquid crystal display (LCD) and
includes a multiplexed backplane drive.
The ICL7136 brings together a combination of high
accuracy, versatility, and true economy. It features auto-zero
to less than 10µV, zero drift of less than 1µV/
oC, input bias
current of 10pA (Max), and rollover error of less than one
count. True differential inputs and reference are useful in all
systems, but give the designer an uncommon advantage
when measuring load cells, strain gauges and other bridge
type transducers. Finally, the true economy of single power
supply operation, enables a high performance panel meter
to be built with the addition of only 10 passive components
and a display.
The ICL7136 is an improved version of the ICL7126,
eliminating the overrange hangover and hysteresis effects,
and should be used in its place in all applications. It can also
be used as a plug-in replacement for the ICL7106 in a wide
variety of applications, changing only the passive
components.