AD7478 Analog Devices Data Sheet manual specifications

1 MSPS, 12-/10-/8-Bit ADCs in 6-Lead SOT-23

AD7476/AD7477/AD7478

FEATURES FUNCTIONAL BLOCK DIAGRAM

Fast throughput rate: 1 MSPS VDD

Specified for VDD of 2.35 V to 5.25 V Low power

12-/10-/8-BIT VIN SUCCESSIVE-

3.6 m W typical at 1 MSPS with 3 V supplies

APPROXIMATION ADC

15 m W typical at 1 MSPS with 5 V supplies Wide input bandwidth 70 d B SNR at 100 k Hz input frequency

CONTROL

Flexible power/serial clock speed management SDATA

LOGIC

No pipeline delays CS

High speed serial interface

AD7476/AD7477/AD7478

SPI®-/QSPI™-/MICROWIRE™-/DSP-compatible Standby mode: 1 μA maximum GND 6-lead SOT-23 package Figure 1.

APPLICATIONS Battery-powered systems Personal digital assistants Medical instruments Mobile communications Instrumentation and control systems Data acquisition systems www.BDTIC.com/ADI High speed modems Optical sensors GENERAL DESCRIPTION PRODUCT HIGHLIGHTS The AD7476/AD7477/AD74781 are, respectively, 12-bit, 10-bit, 1. First 12-/10-/8-Bit ADCs in SOT-23 Packages. and 8-bit, high speed, low power, successive approximation

2. High Throughput with Low Power Consumption.

ADCs. The parts operate from a single 2.35 V to 5.25 V power supply and feature throughput rates up to 1 MSPS. Each part

3. Flexible Power/Serial Clock Speed Management. The

contains a low noise, wide bandwidth track-and-hold amplifier

conversion rate is determined by the serial clock, allowing 4-

that can handle input frequencies in excess of 6 MHz.

the conversion time to be reduced through the serial clock speed increase. This allows the average power consumption

The conversion process and data acquisition are controlled

to be reduced while not converting. The parts also feature a

using CS and the serial clock, allowing the devices to interface

shutdown mode to maximize power efficiency at lower

with microprocessors or DSPs. The input signal is sampled on

throughput rates. Current consumption is 1 μA maximum

the falling edge of CS and the conversion is initiated at this

when in shutdown mode.

point. There are no pipeline delays associated with these parts.

4. Reference Derived from the Power Supply.

The AD7476/AD7477/AD7478 use advanced design techniques

to achieve very low power dissipation at high throughput rates. 5. No Pipeline Delay. The parts feature a standard successive- The reference for the parts is taken internally from VDD. This approximation ADC with accurate control of the sampling

allows the widest dynamic input range to the ADC. Thus, the instant via a CS input and once-off conversion control. analog input range for the parts are 0 V to VDD. The conversion rate is determined by the SCLK. 1 Protected by U.S. Patent No. 6,681,332.

Rev. E 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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