10-Bit A/D Converter with Serial Interface CMOS

These ratiometric 10-bit ADCs have serial interface ports to provide communication with MCUs and MPUs. Either a 10- or 16-bit format can be used. The 16-bit format can be one continuous 16-bit stream or two intermittent 8-bit streams. The converters operate from a single power supply with no external trimming required. Reference voltages down to 4.0 V are accommodated.

The MC145050 has the same pin out as the 8-bit MC145040 which allows an external clock (ADCLK) to operate the dynamic A/D conversion sequence. The MC145051 has the same pin out as the 8-bit MC145041 which has an internal clock oscillator and an end-of-conversion (EOC) output.

• 11 Analog Input Channels with Internal Sample-and-Hold

• Operating Temperature Range: – 40 to 125° C

• Successive Approximation Conversion Time:

MC145050 — 21 µs (with 2.1 MHz ADCLK)

MC145051 — 44 µs Maximum

• Maximum Sample Rate: MC145050 — 38 ks/s

MC145051 — 20.4 ks/s

• Analog Input Range with 5-Volt Supply: 0 to 5 V

• Monotonic with No Missing Codes

• Direct Interface to Motorola SPI and National MICROWIRE Serial Data Ports

• Digital Inputs/Outputs are TTL, NMOS, and CMOS Compatible

• Low Power Consumption: 14 mW

• Chip Complexity: 1630 Elements (FETs, Capacitors, etc.)

• See Application Note AN1062 for Operation with QSPI