Analog Devices Inc. AD7490BCPZ

Overview

AD7490BCPZ from Analog Devices is a 12-bit, 16-channel, successive approximation ADC with integrated sequencer, operating from a single 2.7 V to 5.25 V supply and delivering up to 1 MSPS throughput. It features 69.5 dB SNR at 50 kHz input, 0.5 µA full shutdown current, and SPI/QSPI/MICROWIRE-compatible serial interface. It is used in multichannel system monitoring and power line monitoring where high channel density and low power are critical.

For engineers reviewing the AD7490BCPZ datasheet, AD7490BCPZ pinout, AD7490BCPZ application, or AD7490BCPZ equivalent, key selection criteria include sequencer-configurable 16-channel sampling, VDRIVE-independent 3 V/5 V logic interfacing, 12-bit DC accuracy (±1 LSB INL), wide analog input bandwidth (8.2 MHz full-power), and AEC-Q100 qualification for automotive-grade reliability.

Technical Context

The AD7490BCPZ implements a track-and-hold amplifier with 300 ns acquisition time and no pipeline delay, enabling precise sampling of signals up to 1 MHz. Conversion is initiated on the falling edge of CS and clocked by SCLK - which also serves as the master conversion clock - allowing deterministic timing control down to 800 ns per conversion at 20 MHz SCLK.

Its internal sequencer supports preprogrammed channel cycling across all 16 single-ended inputs, configurable via ADD3–ADD0 address bits and SEQ/SHADOW register controls. Input range selection (0 V to REFIN or 0 V to 2 × REFIN) and output coding (straight binary or twos complement) are software-controlled through dedicated bits in the 16-bit control register.

Key Specifications

Pinout & Package

AD7490BCPZ is packaged in a 32-lead LFCSP (Lead Frame Chip Scale Package) with exposed pad, optimized for thermal performance (θJA = 108.2°C/W) and compact PCB layout. All NC pins must be connected to AGND; exposed pad requires solder connection to GND plane.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar multichannel SAR ADC applications.

Compared with AD7490BCPZ, AD7492BRUZ offers identical speed and supply flexibility but lacks autonomous sequencing - limiting scalability in high-channel-count systems - while ADS8688IPWR trades channel count and power efficiency for enhanced resolution and integrated reference, making it less suitable for compact, battery-sensitive automotive or portable designs.

Availability

AD7490BCPZ is available at Aetrix Electronics and suitable for multichannel system monitoring, battery-powered equipment, and power line monitoring requiring stable component supply, long-term lifecycle support, and AEC-Q100-compliant sourcing.

Supply support for AD7490BCPZ includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Analog Devices, Inc. is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, headquartered in Norwood, MA, with design centers and manufacturing facilities worldwide.

The AD7490BCPZ belongs to Analog Devices' precision data acquisition portfolio, engineered for high-channel-density, low-power, and automotive-qualified applications where deterministic timing, noise immunity, and system integration efficiency are critical.

FAQ

What is the maximum sample rate achievable with AD7490BCPZ?

The AD7490BCPZ achieves a maximum throughput rate of 1 MSPS when operated with a 20 MHz SCLK and VDD between 4.75 V and 5.25 V. At 3 V supplies, the maximum SCLK is 16 MHz, yielding 870 kSPS. The conversion time is fixed at 16 SCLK cycles, so actual rate depends strictly on SCLK frequency and supply conditions specified in the datasheet.

Does AD7490BCPZ support true differential input configurations?

No, the AD7490BCPZ supports only 16 single-ended analog inputs. It does not provide differential input pairs or internal programmable gain amplifiers. Differential measurements require external instrumentation amplifiers or resistor networks before connecting to VIN0–VIN15. The device's channel-to-channel isolation (−82 dB) helps maintain integrity when routing multiple single-ended signals.

How does the VDRIVE pin function in AD7490BCPZ?

The VDRIVE pin sets the logic voltage level for the serial interface (CS, SCLK, DIN, DOUT), independent of VDD. This allows AD7490BCPZ to interface directly with 3 V or 5 V microcontrollers even when VDD is optimized for analog performance (e.g., 5 V for better SNR). VDRIVE must be tied to either 3 V or 5 V - not left floating - and must not exceed VDD + 0.3 V.

Can AD7490BCPZ operate with an external reference other than 2.5 V?

Yes, AD7490BCPZ accepts external references from 1.2 V to VDD, but specified performance (e.g., SNR, INL) is guaranteed only with a 2.5 V ±1% reference. Using other voltages affects full-scale range and may degrade accuracy - particularly gain error match and SNR - unless recalibrated. REFIN impedance must remain ≤36 kΩ at 1 MSPS sampling.

Is AD7490BCPZ pin-compatible with other devices in the AD749x family?

No, AD7490BCPZ is not pin-compatible with AD7492 (8-channel) or AD7495 (single-channel), despite shared architecture and serial interface. Pin counts differ (32-lead LFCSP vs. 24-lead TSSOP for AD7492), and pin functions - especially analog input allocation and NC placement - are unique to each variant. PCB layout must be designed specifically for AD7490BCPZ.