TLC1225M

The TLC1225I and TLC1225M converters are manufactured with Texas Instruments highly efficient Advanced LinCMOSE technology. The TLC1225I and TLC1225M CMOS analog-todigital converters (ADCs) can be operated with a single 5-V supply or with ±5-V supplies. The differential input range is Vref to Vref in both supply configurations. The common-mode input range is ANLG VCC to ANLG VCC+. For single 5-V supply operation, grounding IN corresponds to standard unipolar conversion. For ±5-V supply operation, grounding IN corresponds to standard bipolar conversion. Conversion is performed via the successive-approximation method. The TLC1225x outputs the converted data in a parallel word and interfaces directly to a 16-bit data bus. Negative numbers are given in the 2s-complement data format. All digital signals are fully TTL and CMOS compatible.

This converter TLC1225I and TLC1225M uses a self-calibration technique by which seven of the internal capacitors in the capacitive array of the A/D conversion circuitry can be automatically calibrated. The internal capacitors are calibrated during a nonconversion capacitor-calibrate cycle in which all seven of the internal capacitors are calibrated at the same time. A conversion period requires only 24 clock cycles. Self calibration requires 300 clock cycles. The calibration or conversion cycle can be initiated at any time by issuing the proper command word to the data bus. The self-calibrating technique eliminates the need for expensive trimming of thin-film resistors at the factory and provides excellent performance at low cost.

The TLC1225I is characterized for operation from 40°C to 85°C. The TLC1225M is characterized over the full military temperature range of 55°C to 125°C.