The MAX1202/MAX1203 are 12-bit data-acquisition systems specifically designed
for use in applications with mixed +5V (analog) and +3V (digital) supply voltages. They operate with a
single +5V analog supply or dual ±5V analog supplies, and combine an 8-channel multiplexer,
high-bandwidth track/hold, and serial interface with high conversion speed and low power consumption.
A 4-wire serial interface connects directly to SPI/MICROWIRE devices without external logic, and a
serial strobe output allows direct connection to TMS320-family digital signal processors. The
MAX1202/MAX1203 use either the internal clock or an external serial-interface clock to perform
successive-approximation analog-to-digital conversions. The serial interface operates at up to 2MHz.
The MAX1202 features an internal 4.096V reference, while the MAX1203 requires an external
reference. Both parts have a reference-buffer amplifier that simplifies gain trim. They also have a VL pin
that is the power supply for the digital outputs. Output logic levels (3V, 3.3V, or 5V) are determined by the
value of the voltage applied to this pin.
These devices provide a hard-wired active-low SHDN pin and two software-selectable power-down modes.
Accessing the serial interface automatically powers up the devices. A quick turn-on time enables the
MAX1202/MAX1203 to be shut down between conversions, allowing the user to optimize supply currents.
By customizing power-down between conversions, supply current can drop below 10µA at reduced
sampling rates.
The MAX1202/MAX1203 are available in 20-pin SSOP and DIP packages, and are specified for the
commercial, extended, and military temperature ranges.