Top

3¾ Digit DMM Circuit

Product Details

Key Features

Parametric specs for Display-Oriented ADCs
Resolution (±Counts) 4000
# Input Channels 1
Conv. Rate (ksps) (max) 0.02
Data Bus µP/4
Diff/S.E. Input Diff. Only
External VREF (V) (min) 0
External VREF (V) (max) 6
Unipolar VIN (V) (max) 6
DNL (±LSB) 0.2
INL (±LSB) 16
Package/Pins MQFP/44
PDIP/40
PLCC/44
Budgetary
Price (See Notes)
16.58
View Less

Simplified Block Diagram

Technical Docs

Data Sheet 3¾ Digit DMM Circuit Jan 17, 2022

Support & Training

Search our knowledge base for answers to your technical questions.

Filtered Search

Our dedicated team of Applications Engineers are also available to answer your technical questions. Visit our support portal .

Sampling:
Selecting the Sample button above will redirect to the third-party ADI Sample Site. The part selected will carry over to your cart on this site once logged in. Please create a new account there if you have never used the site before. Contact SampleSupport@analog.com with any questions regarding this Sample Site.

Parameters

Parametric specs for Display-Oriented ADCs
Resolution (±Counts) 4000
# Input Channels 1
Conv. Rate (ksps) (max) 0.02
Data Bus µP/4
Diff/S.E. Input Diff. Only
External VREF (V) (min) 0
External VREF (V) (max) 6
Unipolar VIN (V) (max) 6
DNL (±LSB) 0.2
INL (±LSB) 16
Package/Pins MQFP/44
PDIP/40
PLCC/44
Budgetary
Price (See Notes)
16.58

Key Features

  • 40,000 Count Resolution
  • 0.025% Accuracy
  • 20 Conversions per Second
  • Microprocessor Interface
  • 100µA Operating Supply Current
  • Low External Component Count
  • 5µV Resolution
  • Demonstration Kit Available MAX134/DEMO

Applications/Uses

  • Data Acquisition Systems
  • Data Loggers
  • Digital Panel Meters
  • Weigh Scales

Description

The MAX133 and MAX134 are integrating A/D converters for 3¾ digit multimeters and data acquisition systems such as data loggers and weigh scales. The A/D's internal resolution is ±40,000 counts. An extra digit is supplied as a guard digit to allow autozero or tare of a 4000 count displayed reading to 1/10 of a displayed count. The conversion time is 50ms.

The MAX133 and MAX134 differ only in their microprocessor interface. The MAX133 has a 4 bit multiplexed address/data bus while the MAX134 has 3 separate address lines and a 4 bit bidirectional data bus. Both devices can be used with 4, 8, and 16 bit microprocessors.

When controlled by a microprocessor, the MAX133 and MAX134 can perform auto-ranging measurements from ±400.0mV to ±4000V full scale. External attenuator resistors are required, but range switching is performed by the A/D.

The power supply is typically a 9V battery or ±5V. Operating current is typically 100µA while standby current is only 25µA.

Simplified Block Diagram

MAX133, MAX134: Pin Configuration MAX133, MAX134: Pin Configuration Zoom icon

Technical Docs

Data Sheet 3¾ Digit DMM Circuit Jan 17, 2022

Support & Training

Search our knowledge base for answers to your technical questions.

Filtered Search

Our dedicated team of Applications Engineers are also available to answer your technical questions. Visit our support portal .

Sampling:
Selecting the Sample button above will redirect to the third-party ADI Sample Site. The part selected will carry over to your cart on this site once logged in. Please create a new account there if you have never used the site before. Contact SampleSupport@analog.com with any questions regarding this Sample Site.