General Description

The MAX1497/MAX1499 low-power, 3.5- and 4.5-digit, analog-to-digital converters (ADCs) with integrated light emitting diode (LED) drivers operate from a single 2.7V to 5.25V power supply. They include an internal reference, a high-accuracy on-chip oscillator, and a multiplexed LED display driver. An internal charge pump generates the negative supply needed to power the integrated input buffers for single-supply operation. The ADC is configurable for either a ±2V or ±200mV input range and it outputs its conversion results to an LED and/or to a microcontroller (µC). Microcontroller communication is possible through an SPI™-/QSPI™-/MICROWIRE™-compatible serial interface. The MAX1497 is a 3.5-digit (±1999 count) device and the MAX1499 is a 4.5-digit (±19,999 count) device.

Features

♦ High Resolution

    MAX1499: 4.5 Digits (±19,999 Count)

    MAX1497: 3.5 Digits (±1999 Count)

♦ Sigma-Delta ADC Architecture

    No Integrating Capacitors Required

    No Autozeroing Capacitors Required

    >100dB of Simultaneous 50Hz and 60Hz

    Rejection

♦ Operate from a Single 2.7V or 5.25V Supply

♦ Selectable Input Range of ±200mV or ±2V

♦ Selectable Voltage Reference: Internal 2.048V or External

♦ Internal High-Accuracy Oscillator Needs No External Components

♦ Automatic Offset Calibration

♦ Low Power (Exclude LED Driver Current)

    Maximum 664µA Operating Current

    Maximum 268µA Shutdown Current

♦ Small 32-Pin, 7mm x 7mm TQFP Package (4.5 Digits), 28-Pin SSOP Package (3.5 Digits)

♦ Also Available in a PDIP Package (3.5 Digits)

♦ Multiplexed LED Drivers Resistor-Programmable Segment Current

♦ SPI-/QSPI-/MICROWIRE-Compatible Serial Interface

♦ Extended Temperature Range (-40°C to +85°C)

Applications

    Digital Panel Meters

    Hand-Held Meters

    Digital Voltmeters

    Digital Multimeters