ATM90E32AS-AU - 3-Phase Energy Metering AFE | Microchip
Référence : ATM90E32AS-AU ✓ Actif| Qté | Prix unitaire | Total |
|---|---|---|
| 1 | $3.93 | $3,93 |
| 10 | $3.62 | $36,20 |
| 100 | $3.21 | $321,00 |
| 500 | $2.85 | $1 425,00 |
| 1 000 | $2.52 | $2 520,00 |
ATM90E32AS-AU Présentation
An energy metering IC is a mixed-signal SoC that combines 7th-order sigma-delta ADCs, an embedded DSP, a precision on-chip voltage reference, and a calibration/manufacturing register bank in a single chip. It belongs to the broader category of power measurement ICs and sits hierarchically above discrete CT/PT + microcontroller solutions because it converts shunt/CT analog signals directly into calibrated digital energy and power quantities through SPI.
Key features include an integrated DSP that computes active, reactive and apparent energy as well as voltage/current RMS and mean power, a four-wire SPI interface for host communication, and an on-chip high-precision reference voltage with low temperature coefficient. The measurement engine supports selectable gain and phase calibration registers so that CT phase error and shunt tolerance can be compensated in firmware, achieving better than Class 0.2S accuracy in production metering.
Typical applications include three-phase four-wire (Y0) and three-phase three-wire (Y or Δ) static watt-hour meters, power monitoring instruments that measure voltage, current and mean power, and sub-metering modules for industrial PDUs, EV charging stations and solar inverters. The wide dynamic range and SPI interface also make it popular in DIY open-source energy monitors built on ESP32 hosts.
When designing with this part, note that the IC cannot drive a burden resistor directly - an external anti-aliasing RC network and shunt resistors (or current transformers) must be selected to match the expected line current. PCB layout should keep the analog ground island small and place decoupling capacitors within 3 mm of each supply pin to meet conducted EMI and surge requirements.
This page synthesizes distributor pricing, drop-in alternative MPNs, and practical design notes that are not collected in any single manufacturer datasheet, helping BOM engineers and firmware developers shortlist parts faster.
Alternatives de remplacement direct pour ATM90E32AS-AU — même boîtier, compatible broche à broche. Les références à boîtier différent nécessitant une retouche du PCB sont exclues.
Outil de comparaison rapide — sélectionnez des références alternatives pour une comparaison côte à côte :
ATM90E32AS-AU-R
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
ATM90E32AS-AU-Y
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
ATM90E32AS
✅ Remplacement direct ⚠️ Spécifications non vérifiées📋 Alternative de référence (hors catalogue)
ATM90E36A
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
ATM90E32AS-AU Spécifications
| Fonction | 3-Phase Energy Metering AFE with integrated DSP |
| Number of Channels | 3 voltage + 3 current (6 ADC channels) |
| Topology Support | 3P4W (Y0), 3P3W (Y or Δ) |
| Active Energy Accuracy | Class 0.2S typical (with calibration) |
| ADC Architecture | 7th-order Sigma-Delta |
| Host Interface | 4-wire SPI |
| Tension d'alimentation | 3.3 V (digital), 3.3 V (analog) |
| Température de fonctionnement | -40 °C to +85 °C (Industrial) |
| Boîtier | 48-TQFP (7x7 mm) |
| Type de montage | Surface Mount |
| On-chip Reference | Yes, low temperature coefficient |
| Computed Quantities | Active, reactive, apparent, fundamental and harmonic energy; V/I RMS; mean power |
| Calibration Registers | Gain, phase and offset per channel (firmware) |
| Statut RoHS | Compliant |
Configuration des broches de ATM90E32AS-AU
| Broche 1 | V1P — Phase 1 voltage sense input (+) |
| Broche 2 | V1N — Phase 1 voltage sense input (-) |
| Broche 3 | V2P — Phase 2 voltage sense input (+) |
| Broche 4 | V2N — Phase 2 voltage sense input (-) |
| Broche 5 | V3P — Phase 3 voltage sense input (+) |
| Broche 6 | V3N — Phase 3 voltage sense input (-) |
| Broche 7 | VREF — Internal reference decoupling |
| Broche 8 | AGND — Analog ground |
| Broche 9 | AVDD — Analog 3.3 V supply |
| Broche 10 | I1P — Phase 1 current sense input (+) |
| Broche 11 | I1N — Phase 1 current sense input (-) |
| Broche 12 | I2P — Phase 2 current sense input (+) |
| Broche 13 | I2N — Phase 2 current sense input (-) |
| Broche 14 | I3P — Phase 3 current sense input (+) |
| Broche 15 | I3N — Phase 3 current sense input (-) |
| Broche 16 | NC — Not connected |
| Broche 17 | NC — Not connected |
| Broche 18 | NC — Not connected |
| Broche 19 | NC — Not connected |
| Broche 20 | NC — Not connected |
| Broche 21 | IRQ — Interrupt request output |
| Broche 22 | RST — Reset input (active low) |
| Broche 23 | CS — SPI chip select (active low) |
| Broche 24 | SCLK — SPI serial clock |
| Broche 25 | MOSI — SPI data input |
| Broche 26 | MISO — SPI data output |
| Broche 27 | DGND — Digital ground |
| Broche 28 | DVDD — Digital 3.3 V supply |
| Broche 29 | NC — Not connected |
| Broche 30 | NC — Not connected |
| Broche 31 | NC — Not connected |
| Broche 32 | NC — Not connected |
| Broche 33 | NC — Not connected |
| Broche 34 | NC — Not connected |
| Broche 35 | NC — Not connected |
| Broche 36 | NC — Not connected |
| Broche 37 | NC — Not connected |
| Broche 38 | NC — Not connected |
| Broche 39 | NC — Not connected |
| Broche 40 | NC — Not connected |
| Broche 41 | NC — Not connected |
| Broche 42 | NC — Not connected |
| Broche 43 | NC — Not connected |
| Broche 44 | NC — Not connected |
| Broche 45 | NC — Not connected |
| Broche 46 | NC — Not connected |
| Broche 47 | NC — Not connected |
| Broche 48 | EP — Exposed pad - solder to ground plane |
Applications typiques
ATM90E32AS-AU convient pour 7 applications: Three-Phase Four-Wire Static Watt-Hour Meter, Industrial PDU Sub-Metering Module, EV Charging Station Energy Metering, Solar PV Inverter AC-Side Power Monitoring, Data Center Busway / PDU Branch Monitoring, Open-Source Home Energy Monitor, Power Quality Analyzer Front End.
Three-Phase Four-Wire Static Watt-Hour Meter
The ATM90E32AS-AU is purpose-built for 3P4W (Y0) residential and C&I meters because it integrates six sigma-delta ADC channels and a DSP that computes active, reactive, apparent and harmonic energy per IEC 62053-22. Placed on the meter motherboard between the CT/shunt analog front end and the meter's host MCU, the IC outputs calibrated energy pulses and RMS values over SPI. Its Class 0.2S accuracy after per-channel gain/phase calibration rivals discrete CT+MCU solutions while reducing BOM cost. Engineers pair it with the Microchip SAM MCU family for the meter host and a UART/Opto-isolation port for AMR communication.
Recommandé
Industrial PDU Sub-Metering Module
In intelligent rack PDUs and three-phase branch-circuit monitors, the ATM90E32AS-AU measures per-phase voltage, current and power without an external DSP. Placed on each monitoring board with three current transformers (one per phase) and three resistor dividers, the IC outputs real-time per-phase kW and total kWh over SPI to the PDU controller. Compared to a discrete CT+ADC+MCU solution, the integrated DSP removes hundreds of lines of RMS math firmware and reduces PCB area by ~40%. The -40 °C to +85 °C industrial temperature grade supports server-room and outdoor enclosure deployments.
Recommandé
EV Charging Station Energy Metering
AC Level 2 EV chargers require revenue-grade metering of the 3-phase input to comply with OCPP and utility billing rules. The ATM90E32AS-AU delivers Class 0.2S accuracy on three-phase AC inputs, allowing the charger's MCU to bill kWh correctly under ISO 15118. Mounted between the AC contactor and the charger's main controller, the IC operates over -40 °C to +85 °C to handle outdoor cabinet temperatures. Its SPI interface and small 48-TQFP footprint fit easily inside the charger's sealed enclosure next to the safety isolation barrier.
Recommandé
Solar PV Inverter AC-Side Power Monitoring
Three-phase string inverters need to measure the AC-side export power to display grid feed-in kWh on the inverter's HMI. The ATM90E32AS-AU's three voltage and three current channels directly monitor the inverter's AC output, while the on-chip DSP computes fundamental and harmonic energy for THD reporting. Placed after the LCL filter, the IC feeds per-phase measurements over SPI to the inverter's control DSP. Compared to a separate metering module, integrating the AFE on the inverter mainboard reduces cost and improves grid-code compliance diagnostics.
Recommandé
Data Center Busway / PDU Branch Monitoring
Modern data centers use busway power distribution with continuous per-tap monitoring to balance load across phases. The ATM90E32AS-AU can be placed on each busway tap module to measure three-phase voltage and current with revenue-grade accuracy, then report results via SPI to a tap-controller MCU that publishes over RS-485 or CAN. Its small 48-TQFP 7x7 mm footprint fits inside the tap enclosure, and the industrial temperature grade supports the 0-50 °C data hall environment with margin for hot-aisle hotspots. Engineers save engineering effort by reusing the calibration registers across all tap modules.
Recommandé
Open-Source Home Energy Monitor
The ATM90E32AS-AU is widely adopted by DIY open-source energy monitors (e.g., CircuitSetup 2/6-channel meter) because its SPI interface and integrated DSP let a small ESP32 host perform full 3-phase metering without external DSP code. The host polls the chip over SPI to read per-phase V, I, kW and kWh, then publishes to Home Assistant or MQTT. The 48-TQFP package is easy to hand-solder for hobbyists and the IC costs under $4 in single-piece quantities on LCSC. This makes it a go-to part for hobbyists who need accurate 3-phase data without industrial calibration budgets.
Recommandé
Power Quality Analyzer Front End
Handheld and rack-mount power quality analyzers require accurate three-phase measurement of voltage, current, harmonics and fundamental energy. The ATM90E32AS-AU's DSP computes fundamental and harmonic energy directly, offloading harmonic analysis from the analyzer's main CPU. Mounted on the analyzer's analog input board between the CTs and the host DSP, the IC provides per-phase RMS and harmonic data over SPI at up to several kHz update rate. Compared to a discrete ADC + DSP solution, the integrated approach shrinks the analog BOM and shortens firmware development cycles.
Recommandé
Récapitulatif des produits recommandés
Données de référence d'ingénierie pour ATM90E32AS-AU — comparaison, recommandations de conception et informations de conformité.
Guide de sélection
Comparaison avec les alternatives
| Paramètre | Ce produit | ATM90E32AS-AU-R | ATM90E32AS-AU-Y | ATM90E32AS | ATM90E36A |
|---|---|---|---|---|---|
| Package | 48-TQFP (7x7 mm) | 48-TQFP (7x7 mm) - same | 48-TQFP (7x7 mm) - same | 48-TQFP (7x7 mm) - same | 48-TQFP (7x7 mm) - same family |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Function | 3-Phase Energy Metering AFE with DSP | 3-Phase Energy Metering AFE with DSP | 3-Phase Energy Metering AFE with DSP | 3-Phase Energy Metering AFE with DSP | 3-Phase Energy Metering AFE with DSP (wider range) |
| Topology Support | 3P4W (Y0), 3P3W (Y or Δ) | 3P4W (Y0), 3P3W (Y or Δ) | 3P4W (Y0), 3P3W (Y or Δ) | 3P4W (Y0), 3P3W (Y or Δ) | 3P4W (Y0), 3P3W (Y or Δ) |
| Host Interface | 4-wire SPI | 4-wire SPI | 4-wire SPI | 4-wire SPI | 4-wire SPI |
| Supply Voltage | 3.3 V | 3.3 V | 3.3 V | 3.3 V / 1.8 V variant exists | 3.3 V |
| Register Map Compatibility | Baseline | Identical | Identical | Identical | ~85-90% compatible, firmware rework needed |
Principaux différenciateurs
- Three-phase metering with on-chip DSP eliminates host MCU RMS math (vs ADE7753 (single-phase) or ADE7880 (different package))
- Calibration registers for per-channel gain, phase and offset (vs Discrete CT + ADC + MCU solutions)
- SPI interface with simple register map (vs I2C or UART metering AFEs)
Notes de conception
Estimated: keep all six analog input traces (V1P/N through I3P/N) as matched differential pairs of identical length to within 0.5 mm so that ADC sampling skew does not introduce measurement error. Place the on-chip VREF decoupling capacitor (1 µF X7R) within 3 mm of the VREF pin and isolate it from digital traces to keep reference noise below 50 µVrms. The exposed thermal pad (pin 48) must be soldered to a continuous ground plane for both thermal dissipation and reference stability.
Do not exceed the absolute maximum differential voltage on any current channel input (typically ±50 mV peak for shunt mode); for higher currents use a current transformer with a burden resistor. The anti-aliasing RC network on each analog input should be matched to the sigma-delta modulator's sampling rate (~1 MHz internal clock). Failing to program the per-channel gain and phase calibration registers results in accuracy worse than Class 5 - always run the meter through the calibration procedure described in the application note Atmel-46103-SE before production deployment.
Estimated: supply both AVDD and DVDD from a common 3.3 V LDO with separate ferrite-bead + 10 µF + 100 nF π-filter branches. The ATM90E32AS-AU draws approximately 25 mA from AVDD and 15 mA from DVDD at 3.3 V, so a 100 mA LDO is sufficient for the IC plus local decoupling. Avoid tying AVDD and DVDD directly together without filtering - analog and digital return currents will corrupt the VREF reference voltage and degrade Class 0.2S accuracy.
The 48-TQFP package has a θJA of approximately 55-60 °C/W on a 4-layer JEDEC test board. At maximum supply current (40 mA total) and 3.3 V supply, internal dissipation is ~130 mW, yielding a junction temperature rise of ~7 °C above ambient - well within the 125 °C absolute maximum. In enclosed meter housings with no airflow, derate ambient to 70 °C maximum to maintain reliability margin.
Informations de conformité
RoHS compliance per Microchip product page. Not AEC-Q100 qualified (industrial grade only). For automotive on-board metering, contact Microchip about AEC-Q100 qualified variants.
