MAX1237EUA+TGA8 - 12-Bit 4-Ch 2-Wire Serial ADC | Analog Devices
MPN: MAX1237EUA+TGA8 ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $10.06 | $10.06 |
| 10 | $9.55 | $95.50 |
| 100 | $8.55 | $855.00 |
| 500 | $7.65 | $3,825.00 |
| 1,000 | $6.85 | $6,850.00 |
MAX1237EUA+TGA8 Overview
A SAR ADC is a type of analog-to-digital converter that uses a binary-search successive-approximation register to convert an analog input voltage into a digital code, one bit at a time, in N clock cycles for N-bit resolution. SAR ADCs sit in the broader hierarchy of data-converter ICs (ADC/DAC), themselves a subcategory of signal chain and mixed-signal integrated circuits. They are prized for low latency, deterministic conversion, excellent DC accuracy, and moderate-to-high speed without the pipeline latency of pipelined converters. The MAX1237's internal track/hold, voltage reference, clock, and I2C-compatible 2-wire serial interface integrate the full signal path, simplifying front-end design.
Key features include 12-bit resolution, 4 single-ended input channels, an integrated 2.048V reference (1V external reference option for FS range 1V to VDD), hardware-configurable I2C address pins (the MAX1237 variant supports four selectable slave addresses), an end-of-conversion interrupt, and an automatic low-power shutdown between conversions that drops supply current to under 1 uA. The MAX1237 is pin-compatible with the MAX1236 (4.096V internal reference) within the same family, simplifying reference-voltage selection in the same PCB footprint.
Typical applications include battery-powered data acquisition systems, portable instrumentation, temperature and sensor signal conditioning (with external signal conditioning), industrial process control loops, digital panel meters, and embedded system analog front-ends where I2C bus connectivity, low power, and small package size are required. Designers frequently pair the MAX1237 with microcontrollers featuring I2C controllers (e.g., MAX32xxx, STM32, or PIC families) to build compact 4-channel monitoring systems. The MAX1237EUA+TGA8 packaging variant is supplied in Tape & Reel packaging and is intended for high-volume manufacturing.
Drop-in alternatives for MAX1237EUA+TGA8 — 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 MAX1237EUA+TGA8 (same form factor and footprint) — differing in Package, Number of Input Channels, Sampling Rate, Differential Nonlinearity (DNL), Input Type.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
MAX1236EUA+T
✅ Drop-In📋 Reference alternative (not in catalog)
MAX1237EUA+T
✅ Drop-In📋 Reference alternative (not in catalog)
MAX1237EUA+
✅ Drop-In📋 Reference alternative (not in catalog)
MAX1237EUA
✅ Drop-In📋 Reference alternative (not in catalog)
MAX1236EUA+
✅ Drop-In📋 Reference alternative (not in catalog)
MAX1237EUA+TGA8 Maximum Ratings & Electrical Characteristics
| Resolution | 12 bit |
| Number of Input Channels | 4 single-ended (single-ended) |
| Architecture | SAR (Successive Approximation Register) |
| Sampling Rate | 94.4 ksps (max) |
| Supply Voltage Range | 2.7 V to 3.6 V or 4.5 V to 5.5 V |
| Supply Current (active) | 670 uA at max sampling rate |
| Supply Current (low-power) | below 230 uA |
| Internal Reference Voltage | 2.048 V (MAX1237) |
| External Reference Range | 1 V to VDD |
| Analog Input Range (FS) | 0 to VREF or 0 to VDD (when ext. REF applied) |
| Serial Interface | I2C-compatible 2-wire (400 kHz Fast Mode, 1.7 MHz High-Speed Mode) |
| Package | 8-pin uMAX (uSOP) |
| Operating Temperature Range | -40 C to +85 C |
| Input Type | Single-ended |
| Conversion Latency | SAR synchronous, no pipeline delay |
| RoHS Status | ROHS3 Compliant |
| Mounting Type | Surface Mount |
MAX1237EUA+TGA8 Pin Configuration
| Pin 1 | VDD — Positive supply voltage (2.7V-3.6V or 4.5V-5.5V) |
| Pin 2 | GND — Ground |
| Pin 3 | AIN0 — Analog input channel 0 |
| Pin 4 | AIN1 — Analog input channel 1 |
| Pin 5 | AIN2 — Analog input channel 2 |
| Pin 6 | AIN3 — Analog input channel 3 |
| Pin 7 | SDA — Serial data (I2C) |
| Pin 8 | SCL — Serial clock (I2C) |
Typical Applications
MAX1237EUA+TGA8 is suitable for 6 applications: Portable Battery-Powered Data Acquisition, Industrial Process Control Monitoring, Digital Panel Meter Front-End, Embedded System Analog Front-End, Temperature and Sensor Signal Acquisition, Power-Supply Output Voltage Monitoring.
Portable Battery-Powered Data Acquisition
The MAX1237EUA+TGA8 fits portable battery-powered data acquisition by drawing only 670 uA at 94.4 ksps and dropping below 230 uA in low-power modes, while its automatic shutdown between conversions reduces average current below 1 uA for duty-cycled sampling. Its wide 2.7V-3.6V supply range accepts a single Li-ion cell directly. The internal 2.048V reference provides a clean full-scale range for common sensor signals such as 0-2V analog outputs. The 4 single-ended channels multiplex multiple sensors through a single I2C bus pin pair - a critical advantage for handheld instruments where PCB real estate is constrained. Unlike higher-channel-count ADCs in the family, the 8-pin uMAX footprint keeps the entire analog front-end under 3 mm x 3 mm.
Recommended
Industrial Process Control Monitoring
For industrial process control loops the MAX1237EUA+TGA8 provides 12-bit resolution and 4 single-ended channels sufficient to monitor multiple 4-20 mA loop-derived voltages after signal conditioning. Its I2C-compatible interface supports 400 kHz Fast Mode and 1.7 MHz High-Speed Mode, enabling rapid multi-channel scans across long industrial backplanes. The 8-pin uMAX package operates across -40 C to +85 C, satisfying industrial temperature range requirements. The integrated 2.048V reference and track/hold eliminate the need for external precision references and reduce BOM cost. Designers pair the part with a microcontroller such as the MAX32xxx to build 4-channel sensor nodes that conform to standard industrial bus architectures.
Recommended
Digital Panel Meter Front-End
The MAX1237EUA+TGA8 is well-suited as the ADC front-end in digital panel meters because its 12-bit resolution (4096 LSBs) provides 0.025% nominal code step, and its integrated track/hold, voltage reference, clock, and I2C interface reduce the analog front-end to a handful of external components. The 4 single-ended channels can sequentially digitize voltage, current, and temperature signals via external transducers. The internal 2.048V reference stabilizes the FS range against supply variation, improving display accuracy across battery voltage decay. The 8-pin uMAX package fits into compact meter enclosures where assembly density is critical. The part's automatic shutdown feature extends battery life in portable meters by idling between user-triggered readings.
Recommended
Embedded System Analog Front-End
Embedded microcontroller systems benefit from the MAX1237EUA+TGA8 because it connects directly to any I2C controller on the host MCU through just two wires, leaving the remaining GPIOs free for digital I/O. Its I2C address-select pins allow up to four MAX1237 devices on the same bus, scaling to 16 channels total. The 12-bit resolution and 94.4 ksps throughput suit closed-loop control and monitoring applications such as motor current sensing, power-supply output voltage monitoring, and thermal feedback. The 2.7V-3.6V supply is compatible with 3.3V MCU rails, eliminating level shifters. The small 8-pin uMAX package integrates directly above or below the MCU on 2-layer PCBs.
Recommended
Temperature and Sensor Signal Acquisition
The MAX1237EUA+TGA8 works well as a multi-sensor acquisition front-end when paired with thermistor bridges, RTD signal conditioning, or analog-output temperature sensors such as the TMP series. Its low supply current (sub-1 uA in shutdown) enables duty-cycled temperature readings from battery-powered wireless sensor nodes. The internal 2.048V reference sets a precise excitation reference for ratiometric measurements, improving absolute temperature reading accuracy. Its 4 single-ended inputs can each be assigned to a different sensor location, while the I2C interface multiplexes multiple boards onto a single host bus. The 8-pin uMAX package fits inside TO-92-sized or smaller sensor housings.
Recommended
Power-Supply Output Voltage Monitoring
Power-supply designers use the MAX1237EUA+TGA8 to monitor multiple output rails (3.3V, 1.8V, 1.2V, 0.9V) of a multi-rail PMIC or discrete regulator tree. Its 4-channel input connects to divided-down versions of each rail, and the 12-bit resolution provides 0.8 mV per LSB at a 3.3V FS - sufficient margin for detecting drift and out-of-regulation events. The I2C interface connects to a supervisory MCU or PMIC, allowing the host to log rail health and trigger protection. The wide 4.5V-5.5V supply option supports direct connection to a 5V auxiliary rail. The internal 2.048V reference provides stability for long-term voltage monitoring where absolute accuracy matters.
Recommended
Recommended Products Summary
Engineering reference data for MAX1237EUA+TGA8 — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | MAX1236EUA+T | MAX1237EUA+T | MAX1237EUA+ | MAX1237EUA | MAX1236EUA+ |
|---|---|---|---|---|---|---|
| Package | 8-pin uMAX | 8-pin uMAX | 8-pin uMAX | 8-pin uMAX | 8-pin uMAX | 8-pin uMAX |
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices |
| Resolution | 12 bit | 12 bit | 12 bit | 12 bit | 12 bit | 12 bit |
| Input Channels | 4 single-ended | 4 single-ended | 4 single-ended | 4 single-ended | 4 single-ended | 4 single-ended |
| Internal Reference | 2.048 V | 4.096 V | 2.048 V | 2.048 V | 2.048 V | 4.096 V |
| Sampling Rate | 94.4 ksps | 94.4 ksps | 94.4 ksps | 94.4 ksps | 94.4 ksps | 94.4 ksps |
| Supply Voltage | 2.7V-3.6V / 4.5V-5.5V | 2.7V-3.6V / 4.5V-5.5V | 2.7V-3.6V / 4.5V-5.5V | 2.7V-3.6V / 4.5V-5.5V | 2.7V-3.6V / 4.5V-5.5V | 2.7V-3.6V / 4.5V-5.5V |
| Packaging Form | Tape & Reel (GA8 suffix) | Tape & Reel | Tape & Reel | Tube | Bulk | Tube |
Key Differentiators
- Internal 2.048V reference optimized for low-voltage sensor signals (vs MAX1236EUA+T)
- Lowest quiescent current in the family for battery applications (vs MAX1238/MAX1239)
- Industry-standard I2C-compatible 2-wire interface (vs SPI-interface ADCs (e.g., MAX1030))
Design Notes
The MAX1237EUA+TGA8 draws 670 uA at 94.4 ksps and drops below 230 uA in low-power modes, with automatic shutdown between conversions reducing average current to under 1 uA for duty-cycled sampling. Decouple VDD with a 0.1 uF ceramic capacitor placed within 5 mm of the VDD pin, plus a 1 uF to 10 uF bulk capacitor for transient suppression during conversion bursts.
Route analog input traces (AIN0-AIN3) as short, parallel-routed differential pairs with GND guard traces to minimize digital crosstalk. Keep the analog input traces away from the SDA/SCL traces and from switching regulator or high-frequency digital lines. Place the device close to the analog signal source to reduce trace capacitance and pickup. The exposed pad of the uMAX package ties to GND for thermal and noise reasons; provide multiple vias to a GND copper pour.
Estimated: ensure SDA and SCL are pulled up to VDD with 2.2 kohm to 10 kohm resistors per I2C specification; values too high cause rise-time violations at 400 kHz Fast Mode. Do not exceed VDD on analog inputs; for input signals beyond VREF or VDD, add external clamping or signal conditioning. When using the external reference mode, ensure REF is driven by a low-noise, low-drift source - do not leave floating. Verify I2C address selection (AD0 pin) to avoid conflicts when stacking multiple MAX1237 devices on the same bus.
Compliance Information
ROHS3 Compliant per ICS-Embedded listing. REACH and conflict minerals compliance status not explicitly stated in the verified web data - set to unknown. AEC-Q100 not applicable - this is a general-purpose industrial/commercial ADC, not an automotive-qualified part.
