Analog Devices Inc. AD7298BCPZ-RL7

Overview

AD7298BCPZ-RL7 from Analog Devices is a 12-bit, 1 MSPS, 8-channel SAR ADC with integrated band gap temperature sensor, internal 2.5 V reference, and SPI-compatible serial interface. It operates from a single 2.8 V to 3.6 V supply, supports 0 V to 2.5 V analog input range, and delivers ±1°C temperature accuracy across −40°C to +125°C - used in industrial process monitoring and embedded system health management.

For engineers reviewing the AD7298BCPZ-RL7 datasheet, AD7298BCPZ-RL7 pinout, AD7298BCPZ-RL7 application, or AD7298BCPZ-RL7 equivalent, key selection considerations include channel sequencing capability, TSENSE_BUSY signal timing, VDRIVE logic-level flexibility (1.65 V to 3.6 V), and full power-down current <10 μA at 125°C.

Technical Context

The AD7298BCPZ-RL7 implements a capacitive DAC-based successive approximation architecture with track-and-hold acquisition time of 100 ns and full-power bandwidth of 30 MHz. Its programmable sequencer cycles through up to eight single-ended inputs using CS-triggered conversion with one-cycle latency.

Temperature sensing is performed by a dedicated band gap sensor digitized by the same 12-bit ADC core, yielding 0.25°C resolution and twos-complement output coding. The device uses separate ground pins (GND1 for reference/analog, GND for digital) and requires decoupling at VREF (10 μF to GND1), DCAP (1 μF to GND), and VDD (10 μF + 100 nF to GND).

Key Specifications

Pinout & Package

AD7298BCPZ-RL7 is housed in a 20-lead 4 mm × 4 mm LFCSP package with exposed paddle (EPAD) requiring solder connection to PCB ground for thermal and electrical integrity.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar multichannel SAR ADC with integrated temperature sensing applications.

Compared with AD7298BCPZ-RL7, AD7091R-8BCPZ-RL7 saves cost and offers identical packaging but shifts thermal responsibility to external components, whereas ADS7957IRHBR extends input voltage headroom at the expense of losing monolithic temperature integration - making AD7298BCPZ-RL7 optimal for compact, thermally aware embedded systems.

Availability

AD7298BCPZ-RL7 is available at Aetrix Electronics and suitable for industrial process monitoring, motor drive thermal protection, and telecom base station health management requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for AD7298BCPZ-RL7 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.

The AD7298BCPZ-RL7 belongs to Analog Devices' precision data acquisition product line, designed specifically for space-constrained, thermally aware embedded systems requiring simultaneous analog and temperature measurement without external components.

FAQ

What is the maximum sampling rate of the AD7298BCPZ-RL7 for analog voltage channels?

The AD7298BCPZ-RL7 achieves a maximum throughput rate of 1 MSPS for its eight analog input channels (VIN0–VIN7) when operating with fSCLK = 20 MHz and one-cycle latency. This is confirmed in the Rev. B datasheet Table 1 and supported by the 30 MHz full-power bandwidth of its track-and-hold amplifier. The temperature sensor channel operates at a lower 10 KSPS rate due to longer conversion time.

Does the AD7298BCPZ-RL7 require an external reference voltage?

No, the AD7298BCPZ-RL7 includes an internal 2.5 V reference with ±0.3% accuracy at 25°C and 12 ppm/°C temperature coefficient. The VREF pin can be used to buffer this reference externally or accept a 2.0 V–2.5 V external reference if higher precision or different voltage is needed - but external reference is optional, not required.

How is the temperature sensor output formatted in the AD7298BCPZ-RL7 serial data stream?

The AD7298BCPZ-RL7 outputs temperature data in twos-complement format, distinct from the straight-binary coding used for analog channels. When TSENSE is selected, the 12-bit result represents temperature in 0.25°C steps, with MSB first transmission preceded by a 4-bit channel address. This allows direct interpretation of signed values (e.g., 0x800 = −128°C, 0x000 = 0°C, 0x400 = +64°C).

What is the function of the TSENSE_BUSY pin on the AD7298BCPZ-RL7?

The TSENSE_BUSY pin on the AD7298BCPZ-RL7 is an open-drain status indicator that goes high at the start of a temperature sensor conversion and remains high until completion. It provides hardware synchronization for the host processor, eliminating the need for software polling of conversion status - especially valuable in real-time systems where deterministic timing is critical.

Can the AD7298BCPZ-RL7 operate with different supply voltages for analog and digital domains?

Yes, the AD7298BCPZ-RL7 supports independent supplies: VDD (2.8 V–3.6 V) powers analog and core logic, while VDRIVE (1.65 V–3.6 V) sets the digital I/O voltage level. VDRIVE may be lower than VDD but must not exceed it by more than 0.3 V. This enables seamless interfacing with mixed-voltage FPGAs or microcontrollers without level shifters.