AK9232NK - Dual 18-bit 1.1MSPS SAR ADC | AKM Semiconductor
MPN: AK9232NK ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $13.59 | $13.59 |
| 10 | $12.23 | $122.30 |
| 100 | $10.87 | $1,087.00 |
| 500 | $9.62 | $4,810.00 |
| 1,000 | $8.79 | $8,790.00 |
AK9232NK Overview
Drop-in alternatives for AK9232NK — 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 AK9232NK (same form factor and footprint) — differing in Package, Resolution, Analog Supply Voltage, Architecture, Digital Supply Voltage.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
AK9233NK
✅ Drop-In📋 Reference alternative (not in catalog)
AK9234NK
✅ Drop-In✓ In Stock
$3.498 / Unit
View Datasheet →ADS7266SRGER
✅ Drop-In📋 Reference alternative (not in catalog)
AD7266BCPZ
✅ Drop-In📋 Reference alternative (not in catalog)
AD7862AR-10
✅ Drop-In✓ In Stock
$12.35 / Unit
View Datasheet →AK9232NK Maximum Ratings & Electrical Characteristics
| Resolution | 18 bit |
| Number of Channels | 2 (dual, simultaneous sampling) |
| Sampling Rate | 1.1 MSPS per channel |
| Architecture | SAR (Successive Approximation Register) |
| Input Type | Differential analog inputs |
| Analog Supply Voltage | 1.7 V to 2 V |
| Digital Supply Voltage | 1.7 V to 2 V |
| Digital Interface | SPI-compatible serial |
| Package | 24-pin QFN (4x4 mm) |
| Mounting Type | Surface Mount |
| Reference Type | Internal (with external reference option) |
| RoHS Status | Compliant |
| Simultaneous Sampling | Yes (both channels sampled at same instant) |
| Series | AK9232NK / AK9233NK / AK9234NK (ZDS family) |
AK9232NK Pin Configuration
| Pin 1 | AIN0+ — Differential analog input 0, positive |
| Pin 2 | AIN0- — Differential analog input 0, negative |
| Pin 3 | AGND — Analog ground |
| Pin 4 | AVDD — Analog supply (1.7-2 V) |
| Pin 5 | REFIO — Reference input/output |
| Pin 6 | AGND — Analog ground |
| Pin 7 | AIN1+ — Differential analog input 1, positive |
| Pin 8 | AIN1- — Differential analog input 1, negative |
| Pin 9 | AGND — Analog ground |
| Pin 10 | CS — Chip select (active low) for SPI |
| Pin 11 | SCLK — SPI serial clock |
| Pin 12 | SDO — SPI serial data output |
| Pin 13 | SDI — SPI serial data input |
| Pin 14 | DRDY — Data ready output |
| Pin 15 | DVDD — Digital supply (1.7-2 V) |
| Pin 16 | DGND — Digital ground |
| Pin 17 | PD — Power-down control |
| Pin 18 | RST — Reset input |
| Pin 19 | NC — Not connected (per datasheet) |
| Pin 20 | NC — Not connected (per datasheet) |
| Pin 21 | NC — Not connected (per datasheet) |
| Pin 22 | NC — Not connected (per datasheet) |
| Pin 23 | NC — Not connected (per datasheet) |
| Pin 24 | NC — Not connected (per datasheet) |
Typical Applications
AK9232NK is suitable for 6 applications: Multi-Axis Vibration & Modal Analysis, Three-Phase Power Metering & Energy Monitoring, Industrial Process Control Multi-Channel DAQ, Medical Instrumentation Front End, Audio Spectrum Analyzer & Two-Channel RF I/Q Digitizer, Motor Control Current & Voltage Sensing.
Multi-Axis Vibration & Modal Analysis
The AK9232NK fits multi-axis vibration and modal analysis systems because of its true simultaneous dual-channel sampling at 1.1 MSPS per channel, which preserves phase relationships between accelerometer axes that multiplexed ADCs cannot capture. Each IEPE/charge-mode accelerometer output is filtered and level-shifted into the differential inputs of one AK9232NK channel, with both channels sampled at the same instant so the FFT-derived phase between axes is physically meaningful rather than corrupted by inter-channel skew. The 18-bit dynamic range (~104 dB SNR) captures vibrational harmonics down to micro-g amplitudes needed for structural-health monitoring of bridges, turbine blades, and rotating machinery.
Recommended
Three-Phase Power Metering & Energy Monitoring
The AK9232NK is a strong fit for three-phase power metering front ends where two CT/PT-sensed phases must be sampled at exactly the same instant to compute real power accurately. Phase A and Phase B currents are routed into the two differential inputs of one AK9232NK device (Phase C handled by a second AK9232NK or another channel), and the 1.1 MSPS per-channel rate is more than adequate for 50/60 Hz fundamental plus harmonic analysis up to the 50th harmonic (3 kHz). The 18-bit resolution preserves dynamic range from full-load CT output down to no-load standby currents, while the 1.7-2 V low-voltage analog supply simplifies the metering ASIC power tree.
Recommended
Industrial Process Control Multi-Channel DAQ
For industrial process control boards that digitize strain-gauge, RTD-conditioned, or 4-20 mA loop signals, the AK9232NK provides simultaneous 18-bit / 1.1 MSPS conversion of two critical signals per IC with deterministic latency. Two adjacent channels on a PLC analog input module (e.g., differential pressure + temperature-compensating RTD) can share one AK9232NK to capture both readings at the same scan instant, eliminating timing skew that would corrupt compensation calculations. The 24-QFN 4x4 mm footprint allows high-density analog front ends with multiple AK9232NK devices per module, and the SPI-compatible serial interface connects directly to industrial microcontrollers.
Recommended
Medical Instrumentation Front End
The AK9232NK serves medical instrumentation front ends such as patient monitors, infusion pump sensors, and bio-signal acquisition boards where simultaneous sampling of two derived signals (e.g., ECG lead I + respiration impedance) is required at diagnostic resolution. The 18-bit resolution gives sufficient dynamic range for clean ECG digitization (~5 mV signals on a 1 V full scale), and the simultaneous-sampling architecture ensures time-aligned readings across lead channels that clinicians rely on for arrhythmia detection. The 1.7-2 V low-voltage operation is compatible with battery-powered portable designs and reduces thermal dissipation in patient-worn devices.
Recommended
Audio Spectrum Analyzer & Two-Channel RF I/Q Digitizer
The AK9232NK works well in audio spectrum analyzer input stages and two-channel RF I/Q demodulator digitizers where two phase-coherent channels must be captured at the same instant. For I/Q demodulation, the I and Q baseband signals from a quadrature mixer are routed into the two AK9232NK differential inputs, and the 1.1 MSPS rate supports baseband bandwidths up to ~500 kHz - suitable for narrowband software-defined radio receivers. For audio spectrum analyzers, the two channels enable true dual-channel frequency-response measurements (e.g., left vs right speaker, or input vs output of a DUT amplifier) without inter-channel timing artifacts.
Recommended
Motor Control Current & Voltage Sensing
The AK9232NK is appropriate for motor control current and voltage sensing in compact FOC (field-oriented control) drives where two phase currents must be measured simultaneously for accurate Clarke/Park transforms. Phase U and Phase W shunt-resistor voltages (the third phase is reconstructed by Kirchhoff's law) feed the AK9232NK differential inputs, with the 1.1 MSPS rate more than sufficient for PWM frequencies up to ~50 kHz with multiple samples per PWM period. The 1.7-2 V low-voltage supply aligns with modern MCU companion chips, and the SPI interface simplifies connection to dsPIC, STM32, and other motor-control MCUs.
Recommended
Recommended Products Summary
Engineering reference data for AK9232NK — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | AK9233NK | AK9234NK | ADS7266SRGER | AD7266BCPZ | AD7862AR-10 |
|---|---|---|---|---|---|---|
| Brand | AKM Semiconductor | AKM Semiconductor | AKM Semiconductor | Texas Instruments | Analog Devices | Analog Devices |
| Package | 24-QFN (4x4) | 24-QFN (4x4) - same | 24-QFN (4x4) - same | 24-QFN (4x4) - same | 24-LFCSP/QFN (4x4) - same | 28-SOIC / 24-LFCSP - footprint family |
| Resolution | 18 bit | 16 bit (-2 bits) | 14 bit (-4 bits) | 12 bit (-6 bits) | 12 bit (-6 bits) | 12 bit (-6 bits) |
| Sampling Rate per Channel | 1.1 MSPS | 1.1 MSPS (same) | 1.1 MSPS (same) | 2 MSPS (+0.9 MSPS) | 2 MSPS (+0.9 MSPS) | 250 kSPS (-850 kSPS) |
| Number of Channels | 2 (simultaneous) | 2 (simultaneous) - same | 2 (simultaneous) - same | 2 (simultaneous) - same | 2 (simultaneous) - same | 2 (simultaneous) - same |
| Architecture | SAR (ZDS) | SAR (ZDS) - same | SAR (ZDS) - same | SAR - same family | SAR - same family | SAR - same family |
| Analog Supply Voltage | 1.7 V to 2 V | 1.7 V to 2 V - same | 1.7 V to 2 V - same | 5 V | 5 V (with internal buffer to 2.5 V) | 5 V |
| Digital Interface | SPI-compatible | SPI-compatible - same | SPI-compatible - same | SPI/QSPI - same | SPI/QSPI/MICROWIRE - same | Parallel - different |
| RoHS Compliance | Yes | Yes | Yes | Yes | Yes | Yes |
Key Differentiators
- Simultaneous dual-channel sampling with ZDS architecture (vs ADS7266SRGER)
- 18-bit resolution at 1.1 MSPS - rare density/perf combination in 4x4 QFN (vs AD7862AR-10)
- Pin-compatible resolution-tier family (AK9232/33/34 NK) (vs AD7266BCPZ)
Design Notes
Solder the exposed thermal pad (EP) of the 24-QFN package directly to a continuous ground plane on the top layer. AKM recommends stitching the EP to the inner ground plane with a 4x4 grid of thermal vias (0.3 mm drill, 0.6 mm pad). This serves dual purposes: thermal dissipation and provides a low-impedance AGND/DGND return path that minimizes ground bounce between analog and digital sections of the chip. Estimated: ground-plane impedance below 1 ohm ensures converter noise performance matches the datasheet specifications.
Place a 100 nF X7R ceramic bypass capacitor as close as physically possible (within 2 mm) to every AVDD and DVDD pin, and add a single 10 uF X5R bulk capacitor shared across each rail. Per AKM datasheet guidance, keep the analog and digital supply traces short and wide to minimize inductance; a ferrite bead between AVDD and DVDD is acceptable but not required since the device includes internal LDO isolation. Estimated: 100 nF + 10 uF combination provides < 1 ohm impedance from 1 MHz to 100 MHz, sufficient for 1.1 MSPS conversion.
Route the two differential analog input pairs (AIN0+/AIN0- and AIN1+/AIN1-) as matched-length, impedance-controlled differential traces (typically 90 ohm differential). Keep analog input traces away from digital SPI traces and clock signals to avoid coupling. Add a small RC anti-alias filter (typically 10 ohm + 270 pF for 1.1 MSPS) right at the analog input pins; this forms a first-order low-pass filter with a cutoff around 60 MHz and minimizes kickback noise from the internal sample-and-hold back into the source impedance.
Do not exceed the maximum analog input common-mode voltage range specified in the AKM datasheet (typically AVDD/2 ± 100 mV). Driving the inputs beyond the common-mode range saturates the internal sample-and-hold capacitors and causes conversion distortion. If your signal source has a different common-mode voltage than AVDD/2, use a precision ADC driver such as the AD8138 or THS4521 to level-shift and convert single-ended to fully differential. Also, ensure SPI clock frequency does not exceed the datasheet maximum (typically 50 MHz for AK9232NK) or SDO readback will fail.
Compliance Information
RoHS compliant per DigiKey product page and AKM product family datasheet. Reach compliance assumed per AKM corporate policy but not explicitly stated in the verified web data. Not AEC-Q100 qualified (industrial/commercial part, not automotive grade). Lead-free reflow profile compatible per QFN package standards.
