MAX1497:3.5- and 4.5-Digit, Single-Chip ADCs with LED Drivers and µC Interface

3.5- and 4.5-Digit ADC, LED Display Drivers Reduce Time and Save Board Space

The MAX1497/MAX1499 low-power, 3.5- and 4.5-digit, analog-to-digital converters (ADCs) with integrated lightemitting 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. The MAX1497/MAX1499 do not require external precision integrating capacitors, autozero capacitors, crystal oscillators, charge pumps, or other circuitry required with dual-slope ADCs (commonly used in panel meter circuits). These devices also feature on-chip buffers for the differential signal and reference inputs, allowing direct interface with high-impedance signal sources. In addition, they use continuous internal offset-calibration and offer >100dB rejection of 50Hz and 60Hz line noise. Other features include data hold and peak detection, overrange and underrange detection, and a user-programmable low-battery monitor. The MAX1499 is available in a 32-pin, 7mm x 7mm TQFP package and the MAX1497 is available in 28-pin SSOP and 28-pin PDIP packages. All devices in this family operate over the -40°C to +85°C extended temperature range.

Key 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)
MAX1497, MAX1499: Typical Operating Circuit
MAX1497, MAX1499: Typical Operating Circuit
  • Digital Multimeters
  • Digital Panel Meters
  • Digital Voltmeters
  • Handheld meters
titleDownload file
MAX1497-MAX1499 Data SheetMAX1497-MAX1499.pdf
Part NumberResolution
Conv. Rate
Data BusDiff/S.E. InputInternal VREF
External VREF
External VREF
Bipolar VIN
maxnominalminmaxmaxSee Notes
MAX149720000.0057-SegmentDiff. Only2.04802.04821PDIP(W)/28
$6.82 @1k
MAX149920000LQFP/32$11.53 @500
Design kits & evaluation modules
Related Products
  • MAX1447:3.5- and 4.5-Digit, Single-Chip ADCs with LED Drivers
  • MAX1499:3.5- and 4.5-Digit, Single-Chip ADCs with LED Drivers and µC Interface
  • MAX1491:3.5- and 4.5-Digit, Single-Chip ADCs with LCD Drivers
Ordering Information
Part NumberStatusRecommended ReplacementPackageTempRoHS
MAX1497EAINo Longer AvailableMAX1497EAI+SSOP,;28 pin;81.6 mm²-40°C to +85°CSee data sheet
MAX1497EAI+ActiveSSOP,;28 pin;81.6 mm²-40°C to +85°CLead Free
MAX1497EAI+TActiveSSOP,;28 pin;81.6 mm²-40°C to +85°CLead Free
MAX1497EAI-TNo Longer AvailableMAX1497EAI+TSSOP;28 pin-40°C to +85°CSee data sheet
MAX1497EPINo Longer AvailableMAX1497EPI+PDIP(W),;28 pin;592.6 mm²-40°C to +85°CNo
MAX1497EPI+ActivePDIP(W),;28 pin;592.6 mm²-40°C to +85°CLead Free
MAX1497-MAX1499.pdf MAX1499
MAX1497-MAX1499_cn.pdf MAX1499
Delta-Sigma ADCs Replace Integrating ADCs for Panel Meters MAX1499
MAX1497-MAX1499_cn.pdf MAX1499