The MAX1492/MAX1494 low-power, 3.5- and 4.5-digit,
analog-to-digital converters (ADCs) with integrated liquid
crystal display (LCD) 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 triplexed
LCD driver. An internal charge pump generates the negative
supply needed to power the integrated input buffer
for single-supply operation. The ADC is configurable for
either a ±2V or ±200mV input range and outputs its conversion
results to an LCD and/or to a microcontroller
(µC). µC communication is facilitated through an
SPI-/QSPI-/MICROWIRE-compatible serial interface.
The MAX1492 is a 3.5-digit (±1999 count) device,
and the MAX1494 is a 4.5-digit (±19,999 count) device.
The MAX1492/MAX1494 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 simultaneous rejection of 50Hz and 60Hz
line noise. Other features include data hold and peak
hold, overrange and underrange detection, and a lowbattery
monitor.
The MAX1494 comes in a 32-pin, 7mm x 7mm TQFP
package, and the MAX1492 comes in 28-pin SSOP and
28-pin PDIP packages. All devices in this family operate
over the 0°C to +70°C commercial temperature range.
Key Features
Applications/Uses
High Resolution
MAX1494: 4.5 Digits (±19,999 Count)
MAX1492: 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
Maximum 960µA Operating Current
Maximum 400µA Shutdown Current
Small 32-Pin 7mm x 7mm TQFP Package
(4.5 Digits), 28-Pin SSOP Package (3.5 Digits)
Notes: **This pricing is BUDGETARY, for comparing similar parts. Prices are in
U.S. dollars and subject to change. Quantity pricing may vary
substantially and international prices may differ due to local
duties, taxes, fees, and exchange rates. For volume-specific prices
and delivery, please see the price and availability page
or contact an authorized distributor.