The AD7892 is a high-speed, low-power, 12-bit a /D converter powered by a single +5 V power supply. The device contains a 1.47µs sequential approximation ADC, an on-chip tracking/hold amplifier, an internal + 2.5V reference and an on-chip universal interface architecture that allows serial and parallel connections to the microprocessor. Manufactured in Analog Devices' linearly compatible CMOS (LC2 MOS) process, a mixed-technology process that combines precision bipolar circuits with low-power CMOS logic. It is 24 pin, 0.3 "wide, plastic or sealed in DIP or 24 pin SOIC.
Pin arrangement
The unit accepts analog inputs ranging from ±10 V or ±5 V (AD7892-1), 0 V to + 2.5V (AD7892-2) and ±2.5 V (AD7892-3). Analog input overvoltage protection for the AD7892-1 and AD7892-3 allows input voltages to drop to ±17v or ±7v, respectively, without damaging the port. AD7892 offers two data output formats: single, parallel, 12-bit word, or serial data.
Fast bus access time and standard control inputs ensure easy parallel interface with microprocessors and digital signal processors. High-speed serial interface can be directly connected to microcontroller and digital signal processor serial port. In addition to traditional DC accuracy specifications such as linearity, full scale and offset error, the component also specifies dynamic performance parameters including harmonic distortion and signal-to-noise ratio.
Product highlights
(1)The conversion time of AD7892-3 was 1.47µs and the tracking/hold acquisition time was 200 ns. This gives the unit a throughput of up to 600 kSPS. The throughput of AD7892-1 and AD7892-2 is 500 kSPS.
(2) The AD7892 is powered by a single +5 V power supply with a power consumption of 60mw, making it ideal for low power and portable applications.
(3) The unit provides a high-speed, flexible interface arrangement with parallel and serial interfaces for easy connection to microprocessors, microcontrollers and digital signal processors.
Schematic diagram
Features
● Fast 12-Bit ADC with 1.47s Conversion Time
● 600 kSPS Throughput Rate (AD7892-3)
● 500 kSPS Throughput Rate (AD7892-1, AD7892-2)
● Single Supply Operation
● On-Chip Track/Hold Amplifier
● Selection of Input Ranges:
- 10 V or 5 V for AD7892-1
- 0 V to +2.5 V for AD7892-2
- 2.5V for AD7892-3
● High Speed Serial and Parallel Interface
● Low Power, 60 mW typ
● Overvoltage Protection on Analog Inputs (AD7892-1 and AD7892-3)
