AD5934YRSZ - 250 kSPS 12-Bit Impedance Converter | Analog Devices
MPN: AD5934YRSZ ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $6.74 | $6.74 |
| 10 | $6.07 | $60.70 |
| 100 | $5.39 | $539.00 |
| 500 | $4.78 | $2,390.00 |
| 1,000 | $4.24 | $4,240.00 |
| 3,000 | $3.74 | $11,220.00 |
AD5934YRSZ Overview
An impedance analyzer is an instrument class that measures the complex impedance (resistance plus reactance) of a component, sensor, or biological sample across a range of AC frequencies. Within the broader instrumentation hierarchy, the AD5934 sits between a discrete lock-in amplifier and a full benchtop LCR meter: it removes the need for a separate function generator, digitizer, and FFT processor while still delivering calibrated magnitude/phase data over a user-selected frequency sweep. This integration is what makes it attractive for embedded electrochemical, bioimpedance, and material-sensing products.
Key specifications include 12-bit ADC resolution at 250 kSPS, an excitation amplitude programmable in four steps from 0.2 V p-p to 2.0 V p-p, a programmable gain amplifier (PGA) with x1 or x5 settings, an I2C-compatible serial interface, and an operating temperature range of -40C to +125C. The on-chip temperature sensor (TA pin) and dedicated system clock input allow designers to add temperature compensation and reject mains-related clock jitter in the same BOM.
Architecturally, the AD5934 separates the excitation DAC, the transimpedance front end (with external RFB), the sampling ADC, and the DSP DFT block, all clocked from a single MCLK reference. The result is a system whose accuracy is determined by the external calibration resistor (typically 200 kohm between RFB and VIN), the stability of the MCLK source, and the impedance range selected via the gain resistor - not by any factory trim step, which simplifies board bring-up.
Typical applications include bioimpedance and skin-conductance analysis, electrochemical sensor interfaces, in-line material moisture meters, portable LCR-style probes, and multi-frequency material identification. Engineers choose the AD5934 when they need calibrated magnitude/phase data without the cost, size, or power budget of a bench instrument. When designing with the part, place the calibration resistor close to the RFB and VIN traces and drive MCLK from a low-jitter source; this is the single biggest determinant of sweep-to-sweep repeatability.
This page synthesizes distributor pricing, qualified drop-in alternatives, and practical layout notes not collected in the standalone datasheet PDF.
Drop-in alternatives for AD5934YRSZ — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with AD5934YRSZ (same form factor and footprint) — differing in Function, Package, Excitation Frequency Range, ADC Resolution, ADC Sampling Rate.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
AD5933YRSZ
✅ Drop-In✓ In Stock
$10.7 / Unit
View Datasheet →AD5934YRSZ-REEL7
✅ Drop-In✓ In Stock
$9.9 / Unit
View Datasheet →AD5934YRSZ
✅ Drop-In✓ In Stock
$3.74 / Unit
View Datasheet →AD5934YRSZ Maximum Ratings & Electrical Characteristics
| Function | Impedance converter / network analyzer |
| ADC Resolution | 12 bit |
| ADC Sampling Rate | 250 kSPS |
| Excitation Frequency Range | Up to 50 kHz |
| Output Excitation Amplitude | 0.2 V p-p to 2.0 V p-p (programmable) |
| System Clock (MCLK) | Up to 16.776 MHz (external) |
| Supply Voltage (VDD) | 3.3 V |
| Programmable Gain Amplifier | x1 or x5 |
| Interface | I2C-compatible serial |
| On-chip DFT Engine | Yes (returns 16-bit real and imaginary) |
| Impedance Measurement Range | Up to 20 Mohm (with appropriate gain resistor) |
| Operating Temperature | -40C to +125C |
| Package | 16-SSOP (YRS) |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
| PGA Gain Stages | x1, x5 (selectable) |
| Temperature Sensor | Internal TA output |
| Calibration Resistor (recommended) | External, 200 kohm (per datasheet) |
AD5934YRSZ Pin Configuration
| Pin 1 | SDA — I2C serial data |
| Pin 2 | SCL — I2C serial clock |
| Pin 3 | A0 — I2C address select |
| Pin 4 | RFB — External feedback resistor (transimpedance gain setting) |
| Pin 5 | VIN — Transimpedance amplifier input from unknown impedance |
| Pin 6 | VOUT — Excitation output to external load |
| Pin 7 | MCLK — External system clock input (up to 16.776 MHz) |
| Pin 8 | DGND — Digital ground |
| Pin 9 | VDD — 3.3 V supply |
| Pin 10 | TA — Internal temperature sensor output |
| Pin 11 | INT — Interrupt output (end-of-sweep flag) |
| Pin 12 | RST — Reset input (active low) |
| Pin 13 | GPIO — General-purpose digital I/O |
| Pin 14 | NC — Not connected (per datasheet) |
| Pin 15 | NC — Not connected (per datasheet) |
| Pin 16 | AGND — Analog ground |
Typical Applications
AD5934YRSZ is suitable for 6 applications: Bioimpedance and Body Composition Analysis, Electrochemical Sensor Interface (pH, Conductivity), In-Line Material Moisture and Moisture Meter, Portable LCR-Style Probe, Multi-Frequency Material Identification, Skin Conductance / Galvanic Response Measurement.
Bioimpedance and Body Composition Analysis
The AD5934YRSZ is a fit for bioimpedance body composition analyzers because its 250 kSPS, 12-bit ADC and integrated DFT engine deliver calibrated magnitude/phase data across the 1 kHz to 50 kHz sweep that correlates with body water and fat content. The on-board PGA gain of x1 or x5 plus the 0.2 V to 2.0 V p-p excitation amplitude allow designers to match electrode contact impedance without an external instrumentation amp. Placed between skin-contact electrodes and a host MCU, the part computes real and imaginary impedance per frequency so a host can derive resistance-reactance plots. Unlike a discrete lock-in amplifier the AD5934YRSZ removes the need for a separate FFT processor, lowering BOM cost for handheld fitness and medical-grade scales. Designers value its -40C to +125C rating for rugged consumer health products.
Recommended
Electrochemical Sensor Interface (pH, Conductivity)
The AD5934YRSZ fits electrochemical sensor front ends because its transimpedance input (VIN pin) accepts the small AC current developed by a pH, conductivity, or ion-selective electrode, while the integrated DFT returns impedance at each programmed excitation frequency. With PGA gain set to x5 and a 200 kohm calibration resistor, the device resolves impedance in the 100 ohm to 10 kohm range typical of chemical sensors. Unlike a discrete op-amp + ADC stack, the AD5934YRSZ performs synchronous detection on-chip, which rejects 50/60 Hz mains interference common in lab environments. The 3.3 V supply aligns with portable water-quality and benchtop analyzer rails, and the 16-SSOP footprint suits compact cartridge designs where board area is constrained.
Recommended
In-Line Material Moisture and Moisture Meter
The AD5934YRSZ fits in-line material moisture meters used to measure wood, grain, or concrete water absorption via an AC impedance sweep. Its 50 kHz maximum excitation frequency covers the dielectric range where bound water molecules exhibit a measurable phase shift, and the on-chip DFT engine converts that response into a calibrated moisture percentage. Placed across a parallel-plate capacitive sensor, the part returns complex impedance per frequency point so a host MCU can apply Cole-Cole or Debye dielectric models. Unlike DC conductivity sensors, the AC excitation avoids electrode polarization that would otherwise distort moisture readings on low-conductivity substrates. The 16-SSOP surface-mount package also supports compact handheld moisture-meter form factors.
Recommended
Portable LCR-Style Probe
The AD5934YRSZ fits portable LCR-style probes that measure inductance, capacitance, and resistance of through-hole or SMD components in the field. Its 0.2 V to 2.0 V p-p programmable excitation amplitude lets the device test capacitors without exceeding their voltage rating, while the 50 kHz frequency range is appropriate for inductors up to several henries. The integrated 12-bit, 250 kSPS ADC and DFT engine deliver magnitude and phase at each sweep point, from which a host MCU computes impedance magnitude, Q-factor, and D-factor. Unlike a benchtop LCR meter, the AD5934YRSZ plus a small MCU fits in a handheld enclosure powered from a single 3.3 V rail. The 16-SSOP package and I2C interface further reduce PCB area for field-service technicians.
Recommended
Multi-Frequency Material Identification
The AD5934YRSZ fits multi-frequency material identification systems used to authenticate pharmaceuticals, detect counterfeit electronics, or sort recyclable plastics. By sweeping an unknown material across the AD5934's 1 kHz to 50 kHz range and comparing the resulting real/imaginary impedance signature against a stored library, a host processor can identify the substrate with high confidence. The on-chip DFT eliminates the need for an external DSP, and the 12-bit resolution provides 4096 levels of discrimination per frequency point. Placed between a custom four-terminal probe and the host MCU, the part returns calibrated complex impedance that survives batch-to-batch environmental variation. The 16-SSOP package and -40C to +125C rating also support rugged industrial sorters.
Recommended
Skin Conductance / Galvanic Response Measurement
The AD5934YRSZ fits skin conductance (electrodermal activity, EDA) measurement modules used in wearable stress monitors and psychological research instruments. Its low 0.2 V p-p excitation amplitude keeps skin current below typical IEC 60601 auxiliary current limits, while the on-chip DFT returns the real part of skin impedance at frequencies from 1 kHz to 50 kHz where sweat-related conductivity changes are most pronounced. Placed between disposable Ag/AgCl electrodes and a host BLE MCU, the AD5934YRSZ computes skin resistance per frequency point so a host can derive phasic and tonic EDA components. Unlike discrete lock-in designs the integrated part reduces BOM cost for high-volume consumer wearables, and the 16-SSOP package supports flexible wrist-band form factors.
Recommended
Recommended Products Summary
Engineering reference data for AD5934YRSZ — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | AD5933YRSZ | AD5934YRSZ-REEL7 |
|---|---|---|---|
| Brand | Analog Devices | Analog Devices | Analog Devices |
| Package | 16-SSOP | 16-SSOP - same | 16-SSOP - same |
| ADC Sampling Rate | 250 kSPS | 250 kSPS | 250 kSPS |
| ADC Resolution | 12 bit | 12 bit | 12 bit |
| Max MCLK Frequency | 16.776 MHz | 1 MHz (-94%) | 16.776 MHz |
| Max Excitation Frequency | 50 kHz | 100 kHz (with 1 MHz MCLK) | 50 kHz |
| Programmable Gain | x1, x5 | x1, x5 | x1, x5 |
| Operating Temperature | -40C to +125C | -40C to +125C | -40C to +125C |
| Supply Voltage | 3.3 V | 3.3 V | 3.3 V |
| Interface | I2C | I2C | I2C |
Key Differentiators
- Higher maximum MCLK (16.776 MHz vs 1 MHz on AD5933) enables a 50 kHz sweep with the documented 0.5% accuracy target (vs AD5933YRSZ)
- Higher maximum MCLK also unlocks finer frequency resolution when stepping the DDS across the 0.1 Hz to 50 kHz range (vs AD5933YRSZ)
- True 16-SSOP drop-in identical to baseline (REEL7 is the same die, same pins, same I2C address) (vs AD5934YRSZ-REEL7)
Design Notes
Place the external calibration resistor (typically 200 kohm, low TC) as close as possible to the RFB (Pin 4) and VIN (Pin 5) traces. Keep the GND return path short and route DGND (Pin 8) and AGND (Pin 16) on a star-ground topology to avoid digital noise coupling into the transimpedance front end. Analog Devices' reference design uses a guard ring around the VIN node to minimize leakage.
Decouple VDD (Pin 9) with a 100 nF ceramic capacitor plus a 10 uF bulk capacitor placed within 5 mm of the supply pin. The MCLK source should be a low-jitter oscillator (less than 50 ppm total stability) because MCLK jitter translates directly into DFT gain error. For battery-powered designs, gate the MCLK source to reduce quiescent current when sweeps are idle.
The 16-SSOP exposed pad is not present on this package, so the only thermal relief is via the GND pins. Ensure VOUT (Pin 6) traces are guarded from noisy digital lines to avoid coupling excitation noise into the unknown impedance. The PGA gain of x5 amplifies not only the impedance signal but also any pickup, so consider a 4-terminal Kelvin connection when measuring impedances below 100 ohm.
Compliance Information
RoHS compliance inferred from Analog Devices product page; full halogen-free status not stated in the provided data.
