AD7482 ANALOG DEVICES Data Handbook/Manual

3 MSPS, 12-Bit SAR ADC

AD7482 FEATURES FUNCTIONAL BLOCK DIAGRAM

AVDD AGND CBIAS DVDD VDRIVE DGND

Fast throughput rate: 3 MSPS Wide input bandwidth: 40 MHz No pipeline delays with SAR ADC

BUF REFOUT

Excellent dc accuracy performance REFERENCE

2 parallel interface modes REFSEL REFIN

Low power: 90 m W (full power) and 2.5 m W (nap mode) Standby mode: 2 μA maximum 12-BIT

ALGORITHMIC

Single 5 V supply operation VIN T/H SAR Internal 2.5 V reference

Full-scale overrange mode (using 13th bit) AD7482

System offset removal via user access offset register

MODE1

Nominal 0 V to 2.5 V input with shifted range capability D11

MODE2

14-bit pin compatible upgrade AD7484 available CLIP CONTROL

NAP LOGIC AND I/O

REGISTERS D8

RESET

CONVST

Figure 1.

GENERAL DESCRIPTION www.BDTIC.com/ADI

The AD7482 is a 12-bit, high speed, low power, successive alive for a quick power-up while consuming 2.5 m W, and a approximation ADC. The part features a parallel interface with standby mode that reduces power consumption to a mere 10 μW.

throughput rates up to 3 MSPS. The part contains a low noise, IT

The AD7482 features an on-board 2.5 V reference but can also

wide bandwidth track-and-hold that can handle input frequencies

accommodate an externally provided 2.5 V reference source.

in excess of 40 MHz.

The nominal analog input range is 0 V to 2.5 V, but an offset The conversion process is a proprietary algorithmic successive shift capability allows this nominal range to be offset by ±200 m V. approximation technique that results in no pipeline delays. The This allows the user considerable flexibility in setting the bottom input signal is sampled, and a conversion is initiated on the falling end reference point of the signal range, a useful feature when edge of the CONVST signal. The conversion process is controlled using single-supply op amps.

via an internally trimmed oscillator. Interfacing is via standard

The AD7482 also provides an 8% overrange capability via a

parallel signal lines, making the part directly compatible with

13th bit. Therefore, if the analog input range strays outside the 8-

microcontrollers and DSPs.

nominal by up to 8%, the user can still accurately resolve the The AD7482 provides excellent ac and dc performance specifica- signal by using the 13th bit.

tions. Factory trimming ensures high dc accuracy, resulting in

The AD7482 is powered by a 4.75 V to 5.25 V supply. The part

very low INL, offset, and gain errors.

also provides a VDRIVE pin that allows the user to set the voltage The part uses advanced design techniques to achieve very low levels for the digital interface lines. The range for this VDRIVE pin power dissipation at high throughput rates. Power consumption is 2.7 V to 5.25 V. The part is housed in a 48-lead LQFP package in the normal mode of operation is 90 m W. There are two power and is specified over a −40°C to +85°C temperature range.

saving modes: a nap mode, which keeps the reference circuitry

Rev. A Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other

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