Analog Devices Inc. AD7823YRZ

Overview

AD7823YRZ from Analog Devices is a high-speed, low-power, 8-bit successive approximation ADC with inherent track-and-hold, serial interface, and pseudo-differential analog input. It operates from a single 2.7 V to 5.5 V supply, delivers 4 µs typical conversion time, and is fully specified from –40°C to +125°C - ideal for battery-powered portable instrumentation requiring compact, low-quiescent-power data acquisition.

For engineers reviewing the AD7823YRZ datasheet, AD7823YRZ pinout, AD7823YRZ application, or AD7823YRZ equivalent, key selection considerations include its automatic power-down mode (54 µW at 1 kSPS), microcontroller-compatible 3-wire serial interface (CONVST/SCLK/DOUT), ±0.5 LSB relative accuracy, and support for VREF = VDD to eliminate external reference components.

Technical Context

The AD7823YRZ employs a charge redistribution DAC architecture with internal oscillator and comparator-based successive approximation logic. Its pseudo-differential input (VIN+, VIN–) enables offset cancellation in sensor front-ends, while CONVST double-functionality - initiating conversion on falling edge and enabling serial port on rising edge - supports both high-speed continuous sampling (Mode 1) and automatic power-down operation (Mode 2).

Conversion timing is tightly coupled to CONVST state transitions: in Mode 2, power-up (1.5 µs), conversion (5 µs max), and auto-power-down occur per cycle, yielding scalable power consumption (54 µW @ 1 kSPS → 2.7 mW @ 50 kSPS). The serial interface outputs 8-bit straight-binary data on DOUT synchronized to SCLK, with no external framing required.

Key Specifications

Pinout & Package

AD7823YRZ is housed in an 8-lead microSOIC package (RM-8), 3.0 mm × 3.0 mm, 0.65 mm pitch, with exposed pad for thermal enhancement (θJA = 206°C/W).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 8-bit SAR ADC applications.

Compared with AD7810YRZ and MAX1113EUA+, the AD7823YRZ uniquely balances ultra-low power at low throughput (54 µW), guaranteed operation to +125°C, and true drop-in compatibility with AD7810 in microSOIC - making it optimal for ruggedized, battery-constrained embedded systems demanding proven reliability.

Availability

AD7823YRZ is available at Aetrix Electronics and suitable for battery-powered test equipment, portable medical sensors, automotive cabin monitoring, and industrial motor current sensing requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for AD7823YRZ 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 Wilmington, MA.

The AD7823YRZ belongs to Analog Devices' precision SAR ADC product line, designed specifically for space-constrained, low-power, high-temperature data acquisition in portable and industrial systems - emphasizing integration, robustness, and ease of microcontroller interfacing.

FAQ

What is the maximum sampling rate achievable with the AD7823YRZ?

The AD7823YRZ achieves a maximum throughput rate of approximately 133 kSPS under optimal conditions: VDD = 5 V, fSAMPLE = 133 kHz, and microcontroller serial interface capable of sustaining ≥133 kSPS read cycles. This assumes Mode 1 (high-speed) operation with CONVST held high between conversions and minimal SCLK setup/hold overhead. Real-world rates depend on host MCU timing margins and bus loading.

Can the AD7823YRZ operate without an external voltage reference?

Yes, the AD7823YRZ supports VREF = VDD operation. Connecting VREF directly to VDD configures the ADC for ratiometric measurement, where full-scale input equals VDD. This eliminates the need for an external reference IC, reducing BOM cost and PCB area - provided system accuracy requirements align with VDD tolerance and drift.

How does the AD7823YRZ implement automatic power-down, and what is its impact on timing?

The AD7823YRZ enters automatic power-down when CONVST remains low at the end of conversion (Mode 2). Power-up time is 1.5 µs, conversion time is 5 µs max, so effective cycle time is 6.5 µs. This yields scalable power: 54 µW at 1 kSPS, 540 µW at 10 kSPS. Timing-critical designs must account for the 1.5 µs wake-up latency before conversion starts.

Is the AD7823YRZ pin-compatible with other members of the AD78xx family?

The AD7823YRZ shares the same 8-lead microSOIC (RM-8) pinout with AD7810YRZ and AD7811YRZ, enabling direct PCB replacement for resolution upgrades. However, AD7823YRZ differs electrically: it lacks the AD7810's internal reference and has distinct timing behavior in power-down mode. Always verify firmware timing and reference configuration when substituting.

What is the recommended layout practice for the analog input pins (VIN+, VIN–) of the AD7823YRZ?

For optimal performance, route VIN+ and VIN– differentially with matched trace lengths and minimal stubs; place a 1 nF ceramic capacitor close to VIN+ for AC applications. Keep VIN– stable - its voltage must vary less than ±0.5 LSB during conversion. Avoid routing near digital traces or noisy supplies, and use a solid ground plane beneath the ADC section to minimize noise coupling into the 3.5 pF sampling capacitor.