ADAR7251 4-Channel, 16-Bit, Continuous Time Data Acquisition ADC

The ADAR7251 is a 16-bit, 4-channel, simultaneous sampling analog-to-digital converter (ADC) designed especially for applications such as automotive LSR-FMCW or FSK-FMCW radar systems. Each of the four channels contains a low noise amplifier (LNA), a programmable gain amplifier (PGA), an equalizer, a multibit Σ-Δ ADC, and a decimation filter. The front-end circuitry is designed to allow direct connection to an MMIC output with few external passive components. The ADAR7251 eliminates the need for a high order antialiasing filter, driver op amps, and external bipolar supplies. The ADAR7251 also offers precise channel-to-channel drift matching. The ADAR7251 features an on-chip phase-locked loop (PLL) that allows a range of clock frequencies for flexibility in the system. The CONV_START input and DATA_READY output signals synchronize the ADC with an external ramp for applications such as FSK-FMCW radar. The ADAR7251 supports serial and parallel interfaces at programmable sample rates from 300 kSPS to 1.8 MSPS, as well as easy connections to digital signal processors (DSPs) and microcontroller units (MCUs) in the system.

Applications

Features and Benefits

Low noise: 2.4 nV/√Hz input referred voltage noise at maximum gain setting
Wide input signal bandwidth: 500 kHz at 1.2 MSPS sample rate, 16-bit resolution
Additional sample rates supported: 300 kSPS, 450 kSPS, 600 kSPS, 900 kSPS, and 1.8 MSPS
4 differential simultaneous sampling channels
No active antialiasing filter required

LNA and PGA with 45 dB gain range in 6 dB steps
Selectable equalizer
Flexible data port supports serial or parallel mode
Supports FSK mode for FMCW radar systems
On-chip 1.5 V reference
Internal oscillator/PLL input: 16 MHz to 54 MHz High speed serial data interface
See datasheet for additional features

Analog to Digital Converters

A/D Converters

Data Sheets

Document	note
ADAR7251: 4-Channel, 16-Bit, Continuous Time Data Acquisition ADC (Rev. 0)	PDF 4.32 M

Order Information

Part Number	Package	Packing Qty	Temp Range	Price 100-499	Price 1000+	RoHS
ADAR7251WBCSZ Production	48 LD LFCSP (7x7 w/5.6mm EP)	OTH 260	-40 to 125C	10.59	9	Y
ADAR7251WBCSZ-RL Production	48 LD LFCSP (7x7 w/5.6mm EP)	REEL 2500	-40 to 125C	10.59	9	Y

Evaluation Boards

Part Number	Description	Price	RoHS
EVAL-ADAR7251Z	Evaluation Board	-1	Y

ADAR7251: 4-Channel, 16-Bit, Continuous Time Data Acquisition ADC (Rev. 0) adar7251