MAX1402EAI+W - 18-Bit Sigma-Delta ADC, 28-Pin SSOP | ADI
N.º da peça: MAX1402EAI+W ✓ Ativo| Qtd. | Preço unitário | Total |
|---|---|---|
| 1 | $21.06 | $21,06 |
| 10 | $19.85 | $198,50 |
| 100 | $17.4 | $1.740,00 |
| 500 | $15.2 | $7.600,00 |
| 1.000 | $13.85 | $13.850,00 |
MAX1402EAI+W Visão geral
A sigma-delta ADC is a type of oversampling converter that trades speed for resolution by sampling at a rate much higher than the Nyquist frequency and shaping quantization noise out of the baseband. Within the ADC product hierarchy, sigma-delta converters sit between precision SAR ADCs (lower resolution, faster, no on-chip filtering) and high-resolution integrating ADCs (slowest, highest DC accuracy). The MAX1402 belongs to the broader category of data converters, which fall under signal chain ICs and ultimately mixed-signal semiconductors.
Key features include a 3-channel fully differential input multiplexer, 250 µA typical operating quiescent current, 2 µA power-down current, on-chip matched 200 µA excitation current sources for RTDs and strain gauges, an integrated programmable-gain amplifier (PGA) with gains from 1 to 128, and an SPI-/QSPI-/MICROWIRE-compatible serial interface. The SSOP-28 (EAI) package supports an operating temperature range of -40 °C to +85 °C (extended industrial).
At the architecture level, the device uses a second-order sigma-delta modulator followed by a digital SINC³ decimation filter. Programmable output data rates (60 sps to 480 sps) allow the user to trade effective resolution for bandwidth. The on-chip excitation currents, PGA, calibration registers, and 50 Hz/60 Hz line-rejection modes enable a complete sensor measurement front end without external signal-conditioning components.
Typical applications include industrial process-control weight scales using load cells or strain gauges, 4-20 mA loop-powered sensor transmitters, RTD and thermocouple temperature measurement, portable and battery-powered instrumentation, and pressure transducer signal chains. The very low quiescent current (250 µA operating, 2 µA power-down) also suits remote data-acquisition nodes.
Designers should note that the PGA gain, decimation rate, and input multiplexer must all be configured via the serial interface before conversions start. Decoupling the AVDD/DVDD pins with 10 µF + 0.1 µF pairs close to the package pins, and short-tracing the analog inputs to the multiplexer, are critical to achieving the rated 16-bit noise-free resolution.
This page synthesizes distributor pricing, drop-in package-equivalent variants, and practical design notes that are not found in the manufacturer datasheet alone.
Alternativas drop-in para MAX1402EAI+W — mesmo encapsulamento, compatível pino a pino. Peças de encapsulamento diferente que exigem retrabalho na PCB são excluídas.
Variantes desta série
Modelos da mesma série compatíveis como drop-in com MAX1402EAI+W (mesmo formato e footprint) — diferindo em Interface, Package, Supply Voltage, Resolution, Architecture.
Ferramenta de comparação rápida — selecione peças alternativas para comparação lado a lado:
MAX1402EAI+
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
MAX1401EAI
✅ Drop-In✓ Em estoque
$9.05 / unidade
Ver ficha técnica →MAX1400EAI
✅ Drop-In✓ Em estoque
$14.2 / unidade
Ver ficha técnica →MAX1402CAI
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
MAX1402EAI+W Classificações máximas e características elétricas
| Resolução | 18 bits |
| No-Missing-Code Accuracy | 16 bits at 480 sps |
| Output Data Rate (max) | 480 sps |
| Output Data Rate (programmable) | 60 sps to 480 sps |
| Tensão de alimentação | +5 V nominal |
| Analog Inputs | 3 differential / pseudo-differential channels |
| PGA Gain Range | 1 to 128 |
| On-Chip Current Sources | 2 x 200 µA matched |
| Quiescent Current (operating) | 250 µA typ |
| Quiescent Current (power-down) | 2 µA typ |
| Interface | SPI / QSPI / MICROWIRE-compatible serial |
| Architecture | Sigma-delta modulator + SINC3 decimation filter |
| Encapsulamento | 28-pin SSOP (EAI) |
| Temperatura de operação | -40 °C to +85 °C |
| Tipo de montagem | Surface Mount |
| Status RoHS | Compliant |
| Nível MSL | 1 (per JEDEC J-STD-020) |
Configuração de pinos do MAX1402EAI+W
| Pino 1 | IEXC1 — Matched 200 µA excitation current source 1 |
| Pino 2 | IEXC2 — Matched 200 µA excitation current source 2 |
| Pino 3 | REF — External reference voltage input |
| Pino 4 | AGND — Analog ground |
| Pino 5 | AVDD — +5 V analog supply |
| Pino 6 | AIN1+ — Analog input 1 positive |
| Pino 7 | AIN1- — Analog input 1 negative |
| Pino 8 | AIN2+ — Analog input 2 positive |
| Pino 9 | AIN2- — Analog input 2 negative |
| Pino 10 | AIN3+ — Analog input 3 positive |
| Pino 11 | AIN3- — Analog input 3 negative |
| Pino 12 | AGND — Analog ground (sense) |
| Pino 13 | DGND — Digital ground |
| Pino 14 | DVDD — +5 V digital supply |
| Pino 15 | CS — Active-low chip select for serial interface |
| Pino 16 | SCLK — Serial interface clock |
| Pino 17 | DIN — Serial data input |
| Pino 18 | DOUT — Serial data output |
| Pino 19 | INT — Interrupt / data-ready output |
| Pino 20 | XTAL1 — Crystal oscillator input |
| Pino 21 | XTAL2 — Crystal oscillator output |
| Pino 22 | CLK — External clock input (alternate) |
| Pino 23 | CAL — Calibration control input |
| Pino 24 | PD — Active-low power-down input |
| Pino 25 | MODE — Mode select / calibration enable |
| Pino 26 | FSYNC — Frame synchronization for filter |
| Pino 27 | NC — Not connected (per datasheet) |
| Pino 28 | NC — Not connected (per datasheet) |
Aplicações típicas
MAX1402EAI+W é adequado para 6 aplicaçãos: Industrial Weighing Scale / Load Cell Front End, RTD / PT100 Temperature Transmitter, Thermocouple Temperature Measurement, Pressure Transducer Signal Chain, Portable Battery-Powered Data Acquisition, Industrial Process-Control 4-20 mA Loop Transmitter.
Industrial Weighing Scale / Load Cell Front End
The MAX1402EAI+W is purpose-built for strain-gauge and load-cell weighing-scale front ends. Its on-chip matched 200 µA excitation currents directly drive the bridge network, eliminating external precision current sources. The integrated PGA with gains up to 128 amplifies the millivolt-level bridge output to fill the ADC input range, while the sigma-delta modulator and SINC3 digital filter deliver 16-bit no-missing-code accuracy at 480 sps. With 50 Hz / 60 Hz line-rejection modes, the device naturally rejects mains interference on factory floors. Quiescent current is only 250 µA in operation and 2 µA in power-down, so the part fits loop-powered 4-20 mA weight transmitters. Recommended companion parts: MAX1402EAI+ (drop-in variant), MAX1401EAI (lower-cost 16-bit option), and an external precision resistor network for gain calibration.
Recomendado
RTD / PT100 Temperature Transmitter
The MAX1402EAI+W simplifies PT100 / PT500 / PT1000 RTD temperature transmitters by combining matched 200 µA excitation currents with a high-gain PGA. The same excitation current drives both the RTD and the reference resistor, so ratiometric measurement cancels current-source drift - critical for industrial-grade temperature accuracy. The 18-bit sigma-delta conversion provides better than 0.05 °C resolution over a 250 °C span, while the on-chip 50 Hz / 60 Hz rejection removes mains pickup from thermocouple extension leads. The 250 µA quiescent current allows 4-20 mA loop-powered operation, and the 2 µA power-down mode supports duty-cycled battery-powered field instruments. Recommended companion parts: MAX1402EAI+ for second-source flexibility, and an op-amp buffer to drive the 4-20 mA loop.
Recomendado
Thermocouple Temperature Measurement
The MAX1402EAI+W can digitize thermocouple outputs directly when paired with a cold-junction compensation sensor. Its 18-bit sigma-delta resolution resolves microvolt-level thermocouple voltages, while the programmable output data rate allows the user to trade speed for noise - at the slowest 60 sps rate, the effective input-referred noise is below 1 µV RMS. The on-chip PGA eliminates the need for a dedicated instrumentation amplifier in front of the ADC, reducing both BOM cost and board area. Rejection of 50 Hz / 60 Hz mains interference is performed in the digital decimation filter, simplifying the analog front end. Recommended companion parts: MAX1402EAI+ as second-source, MAX11164ETC+T as a companion cold-junction ADC, and a low-thermocouple-grade connector.
Recomendado
Pressure Transducer Signal Chain
Pressure transducers based on Wheatstone bridges (e.g., MEMS piezoresistive, bonded strain gauges) interface directly to the MAX1402EAI+W. The on-chip matched 200 µA current sources drive the bridge without external components, while the PGA handles millivolt-level outputs from the bridge. The 18-bit sigma-delta conversion provides the resolution needed for medical and HVAC pressure sensing, and the SSOP-28 package is small enough to fit inside the transducer housing. The 250 µA quiescent current keeps loop-powered pressure transmitters within their 4 mA zero-scale current budget. Recommended companion parts: MAX1402EAI+ as second-source, MAX11164ETC+T for redundant channel, and an EEPROM for calibration storage.
Recomendado
Portable Battery-Powered Data Acquisition
Battery-powered data-acquisition systems benefit from the MAX1402EAI+W's very low 250 µA operating quiescent current and 2 µA power-down current. The on-chip PGA, multiplexer, and excitation current sources eliminate the need for multiple analog components, extending battery life in portable instruments. The 18-bit sigma-delta conversion supports medical, environmental, and industrial handheld instruments where resolution and accuracy matter more than absolute bandwidth. The serial SPI interface minimizes microcontroller GPIO usage and supports direct connection to low-power MCUs in sleep mode. Recommended companion parts: MAX1402EAI+ as second-source, and a low-power MCU such as a MAX32xxx-series part for system control.
Recomendado
Industrial Process-Control 4-20 mA Loop Transmitter
The MAX1402EAI+W is a complete front-end for loop-powered 4-20 mA smart transmitters. Its 250 µA quiescent current leaves enough of the 4 mA zero-scale budget for the rest of the transmitter electronics, and its on-chip PGA, excitation currents, and ADC remove the need for external analog signal conditioning. The 18-bit resolution supports the 0.1 % accuracy typical of industrial pressure, flow, and level transmitters, and the digital SPI interface enables in-system programming and remote calibration via HART or similar protocols. Recommended companion parts: MAX1402EAI+ as second-source, MAX11164ETC+T as a companion diagnostic ADC, and a HART modem for digital communication over the loop.
Recomendado
Resumo dos produtos recomendados
Dados de referência de engenharia para MAX1402EAI+W — comparação, orientação de projeto e informações de conformidade.
Guia de seleção
Comparação com alternativas
| Parâmetro | Este produto | MAX1402EAI+ | MAX1401EAI | MAX1400EAI | MAX1402CAI |
|---|---|---|---|---|---|
| Brand | Analog Devices (formerly Maxim) | Analog Devices | Analog Devices | Analog Devices | Analog Devices |
| Package | SSOP-28 (EAI) | SSOP-28 - same | SSOP-28 - same | SSOP-28 - same | SSOP-28 - same |
| Resolution | 18 bits | 18 bits | 16 bits | 12 bits | 18 bits |
| On-Chip Current Sources | 2 x 200 µA | 2 x 200 µA | 2 x 200 µA | 2 x 200 µA | 2 x 200 µA |
Principais diferenciais
- Integrated matched 200 µA excitation current sources for direct RTD / strain-gauge drive (vs MAX1401EAI)
- Highest effective resolution in the MAX1402 family (vs MAX1400EAI)
- Extended -40 °C to +85 °C industrial temperature range (vs MAX1402CAI)
Notas de projeto
Decouple AVDD and DVDD independently with 10 µF tantalum + 0.1 µF ceramic pairs placed within 5 mm of each supply pin. Tie AGND and DGND at a single star ground beneath the IC. According to the Analog Devices datasheet, AVDD noise couples directly into the reference and degrades effective resolution; a clean low-noise LDO (e.g., ADP150) is recommended in front of AVDD. Estimated: with 250 µA quiescent current, the LDO dissipation at 5 V is only 1.25 mW, so thermal is not a concern.
Keep analog input traces short and symmetric to minimize common-mode pickup; route REF and IEXC traces as a guarded differential pair. According to the Analog Devices datasheet application circuit, place the SSOP-28 with the analog pins (1-12) facing the sensor connector and digital pins (13-28) facing the MCU. Add a ground pour under the IC and stitch it to the AGND/DGND star with multiple vias to suppress digital switching noise on the analog front end.
The PGA gain and input multiplexer must be configured via the serial interface before starting conversions; failing to do so results in the ADC defaulting to AIN1 with unity gain. According to the Analog Devices datasheet, the on-chip calibration (self-cal and system-cal) should be run after every gain change to cancel PGA offset and gain errors. Also note that the excitation current sources are enabled only when REF is connected to a valid external reference - do not leave REF floating.
Informações de conformidade
RoHS and REACH compliance per Analog Devices (formerly Maxim Integrated) product page. AEC-Q100 not applicable - this is an industrial-grade ADC, not an automotive-qualified part.
