Analog Devices Inc. AD7450BR

Overview

AD7450BR from Analog Devices is a 12-bit, 1 MSPS successive approximation ADC with fully differential analog input, 3 V/5 V single-supply operation, and SPI/QSPI-compatible serial interface. It features 70 dB SINAD at 300 kHz, 20 MHz full-power bandwidth, and 1 µA max power-down current - deployed in transducer interfaces and battery-powered data acquisition systems.

For engineers reviewing the AD7450BR datasheet, AD7450BR pinout, AD7450BR application, or AD7450BR equivalent, this page delivers verified specifications, SOIC-8 package mapping, differential input biasing guidance, and two validated alternative ADCs for low-power, high-speed sampling in portable instrumentation and motor control.

Technical Context

The AD7450BR uses a charge-redistribution SAR architecture with dual capacitive DACs and an integrated differential track-and-hold amplifier (T/H) featuring 20 MHz –3 dB bandwidth and 50 ps aperture jitter. Its conversion is initiated on the falling edge of CS and clocked by SCLK, eliminating pipeline delay.

All timing-including 16 SCLK-cycle conversion time, 25 ns quiet time, and 10 ns CS pulsewidth-is synchronized to the external serial clock, enabling flexible throughput scaling from 100 kSPS to 1 MSPS. Reference voltage (100 mV–3.5 V) sets both full-scale span (±VREF) and common-mode range, with VCM = VREF recommended for optimal performance.

Key Specifications

Pinout & Package

AD7450BR is housed in an 8-lead SOIC package (SOIC-8), with gull-wing leads, 1.27 mm pitch, and JEDEC MS-012AC standard footprint. Pin 1 is marked by a beveled corner or dot; device orientation follows standard top-view labeling.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-speed, low-power SAR ADC applications.

Compared with AD7450BR, AD7451BR offers integrated reference convenience at the cost of input range adaptability, while ADS8325IBDR trades speed for resolution - making AD7450BR uniquely suited for 1 MSPS, 12-bit, differential-sampling applications where power and layout efficiency matter.

Availability

AD7450BR is available at Aetrix Electronics and suitable for transducer interface, battery-powered data acquisition, and motor control applications requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for AD7450BR 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 is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, headquartered in Norwood, MA.

The AD7450BR belongs to Analog Devices' precision SAR ADC product line, engineered for low-power, high-speed data acquisition in portable, industrial, and automotive sensing systems.

FAQ

What is the maximum input frequency the AD7450BR can accurately digitize?

The AD7450BR has a full-power bandwidth of 20 MHz (–3 dB) and maintains 70 dB SINAD up to 300 kHz input frequency under specified conditions. For signals above 300 kHz, SINAD degrades gradually; the device remains functional but with reduced effective resolution. The 20 MHz T/H bandwidth ensures faithful capture of fast transients, though system-level anti-aliasing filtering is required for Nyquist-compliant sampling.

Does the AD7450BR require an external reference voltage?

Yes, the AD7450BR requires an external reference applied to the VREF pin. It supports VREF from 100 mV to 3.5 V (with 5 V supply) or 100 mV to 2.2 V (with 3 V supply). The reference sets both the full-scale differential input range (±VREF) and influences the allowable common-mode voltage range. A stable, low-noise reference source with ≥0.1 µF local decoupling is mandatory for specified performance.

Can the AD7450BR operate from a 3.3 V supply?

No - the AD7450BR is specified only for 3 V ±10% (2.7 V–3.3 V) or 5 V ±5% (4.75 V–5.25 V) supplies. While it may function at nominal 3.3 V, Analog Devices does not guarantee performance (e.g., throughput, SINAD, power) outside the published 3 V or 5 V ranges. For 3.3 V systems, use the AD7450BR with 3 V supply and adjust VREF accordingly (e.g., 1.25 V) to maintain accuracy.

What is the purpose of the four leading zeros in the AD7450BR serial output?

The AD7450BR outputs a 16-bit serial word comprising four leading zeros followed by the 12-bit two's complement conversion result, MSB first. These zeros provide fixed-word-length framing, simplifying synchronization in microcontroller SPI peripherals that expect consistent bit counts per transaction. They do not represent data but ensure deterministic timing and alignment - especially useful when daisy-chaining multiple ADCs or sharing SCLK with other devices.

How does the AD7450BR handle common-mode voltage on its differential inputs?

The AD7450BR accepts a user-defined common-mode voltage (VCM) set externally between VIN+ and VIN–, with valid range dependent on VREF and supply voltage (e.g., 0.625 V to 4.42 V for VREF = 1.25 V, VDD = 5 V). VCM = VREF is recommended for optimal performance. The device rejects common-mode noise up to 90 dB at 10 kHz, but input signals must stay within absolute ratings: –0.3 V to VDD + 0.3 V per pin.