GENERAL DESCRIPTION

The AD7643 is an 18-bit, 1.25 MSPS, charge redistribution SAR, fully differential, analog-to-digital converter (ADC) that operates from a single 2.5 V power supply. The part contains a high speed, 18-bit sampling ADC, an internal conversion clock, an internal reference (and buffer), error correction circuits, and both serial and parallel system interface ports. The part has no latency and can be used in asynchronous rate applications. The AD7643 is hardware factory calibrated and tested to ensure ac parameters, such as signal-to-noise ratio (SNR), in addition to the more traditional dc parameters of gain, offset, and linearity. The AD7643 is only available in Pb-free packages with operation specified from ?40°C to +85°C.

FEATURES

Throughput: 1.25 MSPS

INL: ±1.5 LSB typical, ±3 LSB maximum (±11 ppm of full scale)

18-bit resolution with no missing codes

Dynamic range: 95dB typical

SINAD: 93.5dB typical @ 20 kHz (VREF= 2.5 V)

THD: ?113dB typical @ 20 kHz (VREF= 2.5 V)

2.048 V internal reference: typical drift 8ppm/°C; TEMP output

Differential input range: ±VREF(VREFup to 2.5 V)

No pipeline delay (SAR architecture)

Parallel (18-, 16-, or 8-bit bus) and serial 5 V/3.3 V/2.5 V interface

SPI?/QSPI?/MICROWIRE?/DSP compatible

Single 2.5 V supply operation

Power dissipation

65mW typical @ 1.25MSPS with internal REF

2 μW in power-down mode

Pb-free, 48-lead LQFP and 48-lead LFCSP_VQ

Pin compatible with the AD7641and other PulSAR ADC’s

APPLICATIONS

Medical instruments

High speed data acquisition/high dynamic data acquisition

Digital signal processing

Spectrum analysis

Instrumentation

Communications

ATE

AD7643屬于集成電路（IC） > 模數(shù)轉(zhuǎn)換器（ADC）。亞德諾半導(dǎo)體技術(shù)有限公司制造生產(chǎn)的AD7643模數(shù)轉(zhuǎn)換器（ADC）模數(shù)轉(zhuǎn)換器（ADC、A/D 或 A 轉(zhuǎn) D）對模擬信號進(jìn)行采樣，例如由麥克風(fēng)采集的聲音或傳感器的輸出，然后將其轉(zhuǎn)換為數(shù)字信號。一般來說，數(shù)字輸出是二進(jìn)制補(bǔ)碼二進(jìn)制數(shù)，與輸入成比例。輸入類型可能是差分、偽差分或單端輸入。模數(shù)轉(zhuǎn)換器可按照位數(shù)、采樣率、輸入數(shù)、接口、轉(zhuǎn)換器數(shù)和架構(gòu)（例如自適應(yīng)增量、雙斜率、折疊、流水線、SAR、三角積分、兩步式）進(jìn)行選擇。