MAX1246ACEE - 12-Bit 4-Ch 133ksps Serial ADC | Maxim Integrated
MPN: MAX1246ACEE ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $14.01 | $14.01 |
| 10 | $12.61 | $126.10 |
| 100 | $11.21 | $1,121.00 |
| 500 | $9.81 | $4,905.00 |
| 1,000 | $8.41 | $8,410.00 |
MAX1246ACEE Overview
A successive-approximation ADC is a type of Nyquist-rate data converter that performs one bit decision per clock cycle using an internal binary-weighted capacitor DAC and a comparator. After N cycles (N being the resolution), the result represents the input voltage. SAR ADCs are favored over delta-sigma and pipelined ADCs when low latency, no pipeline delay, and deterministic acquisition are required. The MAX1246 belongs to the data converter -> ADC -> SAR ADC -> precision 12-bit ADC category, making it suitable for general-purpose mixed-signal measurement tasks where both speed and resolution are required without switching-converter-induced latency.
Key electrical features include 133 ksps throughput, an internal 2.5V reference (with external reference option), ±1.5% reference-buffer trim range, single-supply +2.7V to +3.6V operation, hardware- or software-controlled power-down (<1 µA), 4 single-ended / 2 differential analog input channels, and an SPI/QSPI/MICROWIRE-compatible serial interface. The QSOP-16 footprint provides a compact surface-mount solution and the device is specified over the 0°C to +70°C commercial temperature range. Hardware shutdown via the SHDN pin combined with internal wake-up timing allows duty-cycled sampling for battery-friendly designs.
The MAX1246's internal reference, integrated input multiplexer, and small-footprint serial interface target applications that need multi-channel acquisition in space-constrained boards, such as portable instrumentation, data loggers, sensor conditioning front-ends, and process-control I/O modules. Pin-for-pin compatibility with the MAX1247 family allows designers to scale resolution (10/12-bit) or reference strategy (internal vs external) without PCB rework.
When designing with the MAX1246ACEE, decouple VDD and VREF locally with 0.1 µF and 10 µF capacitors, keep analog and digital grounds tied to a single star point, and route REF away from fast digital edges to preserve 12-bit linearity. For best AC performance at full 133 ksps throughput, ensure the host SPI clock is within the 0.1 MHz to 4 MHz spec range.
This page consolidates distributor pricing as of 2026-10-14, drop-in same-brand and cross-brand alternatives in the QSOP-16 footprint, and practical PCB layout guidance not always visible from the manufacturer datasheet alone.
Drop-in alternatives for MAX1246ACEE — 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 MAX1246ACEE (same form factor and footprint) — differing in Architecture, Input Type, Operating Temperature, Resolution.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
MAX1246ACEE+
✅ Drop-In📋 Reference alternative (not in catalog)
MAX1246BCEE
✅ Drop-In✓ In Stock
$7.1 / Unit
View Datasheet →MAX1246ACEE+T
✅ Drop-In📋 Reference alternative (not in catalog)
MAX1246AEEE+
✅ Drop-In📋 Reference alternative (not in catalog)
MAX1246BCEE+
✅ Drop-In📋 Reference alternative (not in catalog)
MAX1246BEEE+T
✅ Drop-In📋 Reference alternative (not in catalog)
MAX1246ACEE Maximum Ratings & Electrical Characteristics
| Resolution | 12 bits |
| Architecture | SAR (Successive Approximation) |
| Number of Channels | 4 single-ended / 2 differential |
| Sampling Rate | 133 ksps |
| Supply Voltage (Analog) | 2.7 V to 3.6 V |
| Supply Voltage (Digital) | 2.7 V to 3.6 V |
| Supply Current at 133 ksps | 1.3 mA (typ) |
| Power-Down Current | < 1 µA |
| Internal Reference Voltage | 2.5 V |
| Reference Trim Range | ±1.5% (via REFADJ) |
| Input Type | Single-Ended or Differential |
| Serial Interface | SPI / QSPI / MICROWIRE compatible |
| Operating Temperature | 0 °C to +70 °C (commercial, 'C' suffix) |
| Package | 16-pin QSOP |
| Mounting Type | Surface Mount |
MAX1246ACEE Pin Configuration
| Pin 1 | AIN1 — Analog Input 1 (single-ended) / Positive differential input 1 |
| Pin 2 | AIN2 — Analog Input 2 (single-ended) / Negative differential input 1 |
| Pin 3 | AIN3 — Analog Input 3 (single-ended) / Positive differential input 2 |
| Pin 4 | AIN4 — Analog Input 4 (single-ended) / Negative differential input 2 |
| Pin 5 | AGND — Analog Ground |
| Pin 6 | REFADJ — Reference Adjust input for ±1.5% trim |
| Pin 7 | REF — Reference Input/Output (internal 2.5V or external reference) |
| Pin 8 | VDD — Analog Supply Voltage (+2.7V to +3.6V) |
| Pin 9 | DGND — Digital Ground |
| Pin 10 | SHDN — Active-Low Shutdown input (logic low = power-down) |
| Pin 11 | NC — Not connected (per datasheet) |
| Pin 12 | NC — Not connected (per datasheet) |
| Pin 13 | VDD — Digital Supply Voltage (+2.7V to +3.6V) |
| Pin 14 | SCLK — Serial Clock input |
| Pin 15 | CS — Active-Low Chip Select input |
| Pin 16 | DOUT — Serial Data Output (ADC conversion result) |
Typical Applications
MAX1246ACEE is suitable for 6 applications: Portable Data Acquisition Logger, Industrial Process Control I/O Module, Sensor Signal Conditioning Front-End, Battery-Powered Handheld Meter, Patient Monitoring & Medical Sensor Interface, Rack-Mount Test & Measurement Instrument.
Portable Data Acquisition Logger
The MAX1246ACEE fits battery-powered data loggers thanks to its 1.3 mA active supply current at 133 ksps and <1 µA power-down current, enabling multi-day deployments on a single Li-ion cell. With four single-ended channels it can directly digitize thermocouple, RTD-conditioned, or 4-20 mA-scaled sensor outputs without an external analog multiplexer. The internal 2.5V reference eliminates a discrete ADR03 reference, reducing BOM cost and the 1 cm² of PCB area it would otherwise occupy. Place 0.1 µF and 10 µF decoupling on VDD and REF adjacent to the IC pins; route REF away from SPI clock edges to preserve 12-bit linearity at full throughput.
Recommended
Industrial Process Control I/O Module
In a 4-20 mA input module the MAX1246ACEE's 4-channel multiplexer accepts four conditioned current-loop signals sequentially at 133 ksps aggregate throughput, more than adequate for the typical 10-100 Hz update rate demanded by PLC backplanes. Its 3.3V single-supply operation simplifies board design, while the SPI-compatible serial interface connects directly to most ARM Cortex-M0/M4 microcontrollers without level shifters. For higher-accuracy process-control loops requiring tighter linearity, the B-grade MAX1246BCEE can be substituted without PCB changes, giving engineers a single SKU path for both commercial and precision variants of the same module.
Recommended
Sensor Signal Conditioning Front-End
Bridge sensors (load cells, strain gauges) and other differential-output transducers pair naturally with the MAX1246ACEE's 2-channel differential input mode, eliminating an external instrumentation amplifier in many low-bandwidth applications. Its internal 2.5V reference can be used ratiometrically to drive both the bridge excitation and the ADC reference, cancelling excitation supply drift in the conversion result. Keep the PCB analog ground plane unbroken under the part and route DOUT, SCLK, and CS over the digital ground region only after crossing the AGND/DGND split, to keep digital switching noise out of the 12-bit measurement.
Recommended
Battery-Powered Handheld Meter
Handheld multimeters and clinical point-of-care meters benefit from the MAX1246ACEE's small QSOP-16 footprint (about 30 mm² including decoupling), low 1.3 mA active supply current, and <1 µA shutdown current that lets the MCU gate conversions during idle display intervals. Four single-ended channels are sufficient for measuring a primary signal plus three auxiliary reference voltages for self-calibration at power-up. The internal 2.5V reference provides adequate accuracy for the typical 0.5% handheld-meter requirement without a separate ADR4525, saving both cost and PCB area.
Recommended
Patient Monitoring & Medical Sensor Interface
Low-power multi-channel patient monitors benefit from the MAX1246ACEE's sequential multiplexer that can digitize ECG, SpO2, temperature, and respiration channels in a 4-input single-ended configuration. The <1 µA power-down mode allows duty-cycling between samples, extending battery life on wearable patches. While the commercial 0-70 °C grade is sufficient for body-worn devices, designs requiring extended temperature margin for clinical-grade equipment can substitute the MAX1246AEEE+ (-40 °C to +85 °C) without any PCB change.
Recommended
Rack-Mount Test & Measurement Instrument
Test instrument front-ends that scan 4-16 channels per second (such as rack-mounted data acquisition modules, battery cyclers, and lab bench multimeters) use the MAX1246ACEE's 133 ksps aggregate throughput to digitize many channels sequentially at per-channel rates above 30 ksps. The internal reference is adequate for 0.1%-class measurements, and the 4-channel mux lets designers daisy-chain multiple MAX1246 ICs sharing one SPI bus for higher channel counts. Refer to the manufacturer datasheet's typical application circuit for the recommended REFADJ resistor-divider that trims the reference to within ±1.5%.
Recommended
Recommended Products Summary
Engineering reference data for MAX1246ACEE — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | MAX1246ACEE+ | MAX1246BCEE | MAX1246ACEE+T | MAX1246AEEE+ | MAX1246BCEE+ | MAX1246BEEE+T |
|---|---|---|---|---|---|---|---|
| Brand | Maxim Integrated | Maxim Integrated | Maxim Integrated | Maxim Integrated | Maxim Integrated | Maxim Integrated | Maxim Integrated |
| Package | 16-pin QSOP | 16-pin QSOP - same | 16-pin QSOP - same | 16-pin QSOP - same | 16-pin QSOP - same | 16-pin QSOP - same | 16-pin QSOP - same |
| Resolution | 12 bits | 12 bits | 12 bits | 12 bits | 12 bits | 12 bits | 12 bits |
| Sampling Rate | 133 ksps | 133 ksps | 133 ksps | 133 ksps | 133 ksps | 133 ksps | 133 ksps |
| Channels | 4 SE / 2 DIFF | 4 SE / 2 DIFF | 4 SE / 2 DIFF | 4 SE / 2 DIFF | 4 SE / 2 DIFF | 4 SE / 2 DIFF | 4 SE / 2 DIFF |
| Internal Reference | 2.5 V | 2.5 V | 2.5 V | 2.5 V | 2.5 V | 2.5 V | 2.5 V |
| Supply Voltage | 2.7 V to 3.6 V | 2.7 V to 3.6 V | 2.7 V to 3.6 V | 2.7 V to 3.6 V | 2.7 V to 3.6 V | 2.7 V to 3.6 V | 2.7 V to 3.6 V |
| Operating Temperature | 0 °C to +70 °C | 0 °C to +70 °C | 0 °C to +70 °C | 0 °C to +70 °C | -40 °C to +85 °C (extended) | 0 °C to +70 °C | -40 °C to +85 °C (extended) |
| RoHS | Non-RoHS (legacy) | RoHS | Non-RoHS (legacy) | RoHS | RoHS | RoHS | RoHS |
| Grade / Binning | A grade (commercial) | A grade (commercial) | B grade (tighter linearity) | A grade (commercial) | A grade (extended temp) | B grade (tighter linearity) | B grade (extended temp) |
Key Differentiators
- Higher-accuracy B-grade drop-in upgrade path (vs MAX1246BCEE)
- Extended temperature grade available in same footprint (vs MAX1246AEEE+)
- RoHS-compliant ordering code for new designs (vs MAX1246ACEE+)
Design Notes
Place 0.1 µF ceramic and 10 µF tantalum or ceramic bypass capacitors within 2 mm of the VDD pins (pins 8 and 13) and the REF pin (pin 7). The internal reference is sensitive to high-frequency supply noise; a single shared 10 µF cap at the supply entry is not sufficient for 12-bit accuracy at 133 ksps. Add a ferrite bead between analog VDD and digital VDD if the host MCU draws switching current from the same rail.
Use a single uninterrupted ground plane under the IC with the analog and digital ground split only briefly under the AGND/DGND pins (pins 5 and 9). Route REF (pin 7) and the analog input traces (pins 1-4) on the opposite side of the board from SCLK (pin 14), DOUT (pin 16), and CS (pin 15). Keep analog input traces short and guarded with ground to minimize crosstalk from the digital interface.
Do not leave REF floating when the internal reference is disabled. Tie REF through a 0.1 µF bypass to AGND even in external-reference mode. Do not exceed the maximum analog input voltage (VDD + 0.3V) on any AIN pin during power-up transients. Driving the SHDN pin (pin 10) logic high above VDD before VDD ramps can cause latch-up; add a series resistor or drive SHDN from a GPO that tracks VDD.
Compliance Information
The MAX1246ACEE (no + suffix) is the legacy non-RoHS Maxim Integrated part; the RoHS-compliant equivalent is the MAX1246ACEE+. This commercial-temperature part is not AEC-Q100 qualified - choose MAX1246AEEE+ or MAX1246BEEE+T for extended temperature operation.
