GENERAL DESCRIPTION

The AD7470/AD7472 are 10-bit/12-bit high speed, low power, successive approximation ADCs. The parts operate from a single 2.7 V to 5.25 V power supply and feature throughput rates up to 1.5 MSPS for the 12-bit AD7472 and up to 1.75 MSPS for the 10-bit AD7470. The parts contain a low noise, wide bandwidth track-and-hold amplifier that can handle input frequencies in excess of 1 MHz.

The AD7470/AD7472 use advanced design techniques to achieve very low power dissipation at high throughput rates. With 3 V supplies and 1.5 MSPS throughput rates, the AD7470 typically consumes, on average, just 1.1 mA. With 5 V supplies and 1.75 MSPS, the average current consumption is typically 1.6 mA. The part also offers flexible power/throughput rate management. Operating the AD7470 with 3 V supplies and 500 kSPS throughput reduces the current consumption to 713 µA.

At 5 V supplies and 500 kSPS, the part consumes 944 µA.

It is also possible to operate the parts in an auto sleep mode, where the part wakes up to do a conversion and automatically enters sleep mode at the end of conversion. This method allows very low power dissipation numbers at lower throughput rates. In this mode, the AD7472 can be operated with 3 V supplies at 100 kSPS, and consume an average current of just 124 µA. At 5 V supplies and 100 kSPS, the average current consumption is 171 µA.

FEATURES

Specified for VDD of 2.7 V to 5.25 V

1.75 MSPS for AD7470 (10-Bit)

1.5 MSPS for AD7472 (12-Bit)

Low Power

AD7470:

3.34 mW Typ at 1.5 MSPS with 3 V Supplies

7.97 mW Typ at 1.75 MSPS with 5 V Supplies

AD7472:

3.54 mW Typ at 1.2 MSPS with 3 V Supplies

8.7 mW Typ at 1.5 MSPS with 5 V Supplies

Wide Input Bandwidth

70 dB Typ SNR at 500 kHz Input Frequency

Flexible Power/Throughput Rate Management

No Pipeline Delays

High Speed Parallel Interface

Sleep Mode: 50 nA Typ

24-Lead SOIC and TSSOP Packages