MAX1393ETB+T - 12-Bit 312.5ksps SAR ADC | Maxim Integrated
MPN: MAX1393ETB+T ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $4.95 | $4.95 |
| 10 | $4.45 | $44.50 |
| 100 | $3.7 | $370.00 |
| 500 | $3.2 | $1,600.00 |
| 1,000 | $2.85 | $2,850.00 |
MAX1393ETB+T Overview
An SAR (Successive Approximation Register) ADC is a type of analog-to-digital converter that uses a binary search algorithm and an internal capacitive DAC to digitize an analog input one bit at a time per clock cycle. SAR ADCs sit within the broader data-converter hierarchy (ADC -> data converter -> signal chain IC -> mixed-signal semiconductor) and are favored for applications needing moderate resolution at low-to-moderate sampling rates, deterministic conversion latency, and very low power consumption.
The MAX1393 distinguishes itself with true-differential input capability in a single-channel configuration (or two single-ended channels), micropower operation suited for battery-powered systems, automatic shutdown between conversions to extend battery life, fast wake-up to resume sampling with minimal latency, and a compact TDFN-10 (3x3 mm) exposed-pad package that simplifies thermal dissipation and PCB layout. It supports an SPI/QSPI/MICROWIRE-compatible serial interface, simplifying connection to most modern microcontrollers and DSPs without bus-parallel pin overhead.
Architecturally, the MAX1393 combines a track/hold front-end, a charge-redistribution DAC, a SAR control core, and an internal 2.5V reference option (with external reference override). The SAR conversion cycle completes in approximately 18 clock cycles, with the SCLK / DOUT / CS three-wire bus enabling throughput up to 312.5 ksps at the rated 3V nominal VDD. The integrated reference and true-differential input reduce the external BOM, lowering both cost and PCB area for space-constrained designs.
Typical applications include portable and battery-powered instrumentation, sensor signal conditioning (thermistors, strain gauges, RTDs), handheld medical and fitness monitoring devices, industrial process monitoring loops (4-20 mA digitizers), data loggers, and consumer audio front-ends where 12-bit resolution is sufficient. The automatic shutdown feature extends coin-cell runtime in periodic-sampling architectures such as remote telemetry nodes.
When designing with the MAX1393, ensure the input signal common-mode voltage is within the supply range and use the exposed pad for thermal relief and low-impedance ground. Add a 0.1 uF decoupling capacitor close to VDD; place the reference capacitor near AVDD/REF as the datasheet recommends for optimal AC performance.
This page synthesizes current distributor stock, parametric drop-in alternatives, and design considerations not aggregated in the manufacturer datasheet alone, sourced from Maxim Integrated documentation and Octopart distributor feeds.
Drop-in alternatives for MAX1393ETB+T — 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 MAX1393ETB+T (same form factor and footprint) — differing in Number of Channels, Package, Input Type, Resolution, Operating Temperature.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
MAX1393MTB+T
✅ Drop-In✓ In Stock
$4.35 / Unit
View Datasheet →MAX1393ETB+
✅ Drop-In📋 Reference alternative (not in catalog)
MAX1396ETB+T
✅ Drop-In📋 Reference alternative (not in catalog)
MAX1396MTB+T
✅ Drop-In✓ In Stock
$3.18 / Unit
View Datasheet →MAX11164ETC+T
✅ Drop-In✓ In Stock
$5.54 / Unit
View Datasheet →MAX1393ETB+T Maximum Ratings & Electrical Characteristics
| Number of Channels | 1 (true-differential) / 2 (single-ended) |
| Resolution | 12 bit |
| Architecture | SAR (Successive Approximation Register) |
| Sampling Rate | 312.5 ksps |
| Supply Voltage (VDD) | 1.5 V to 3.6 V |
| Input Type | True-Differential / Single-Ended (configurable) |
| Serial Interface | SPI / QSPI / MICROWIRE compatible, 3-wire |
| Internal Reference | 2.5 V (external reference supported) |
| Package | 10-TDFN (3 mm x 3 mm) exposed pad |
| Mounting Type | Surface Mount |
| Automatic Shutdown | Yes (auto power-down between conversions) |
MAX1393ETB+T Pin Configuration
| Pin 1 | AIN+ — Positive analog input (true-differential mode) or AIN1 (single-ended mode) |
| Pin 2 | AIN- — Negative analog input (true-differential mode) or AIN0 (single-ended mode) |
| Pin 3 | GND — Ground reference for analog and digital domains |
| Pin 4 | VDD — Power supply input (1.5 V to 3.6 V) |
| Pin 5 | REF — Reference voltage input/output (internal 2.5 V or external reference) |
| Pin 6 | CS — Chip select (active low) for serial interface |
| Pin 7 | SCLK — Serial clock input |
| Pin 8 | DOUT — Serial data output (SPI/QSPI/MICROWIRE) |
| Pin 9 | SHDN — Shutdown input (active low) for automatic power-down |
| Pin 10 | NC — Not connected (per datasheet); internal bond to GND |
Typical Applications
MAX1393ETB+T is suitable for 7 applications: Portable Battery-Powered Instrumentation, Sensor Signal Acquisition (RTD/Thermistor/Bridge), Handheld Medical and Fitness Monitoring Devices, Industrial Process Monitoring (4-20 mA Loop Digitization), Consumer Audio and Voice Front-End, Remote IoT Sensor Nodes, Data Logger Front-End (Environmental Monitoring).
Portable Battery-Powered Instrumentation
The MAX1393ETB+T's 1.5V to 3.6V single-supply operation and automatic shutdown between conversions extend battery runtime in handheld multimeters and portable data loggers. Its 312.5 ksps throughput captures fast transients in sensor sweeps while the micropower shutdown (sub-microamp class) preserves coin-cell life across thousands of hourly samples. The 10-TDFN exposed pad provides thermal relief for continuous sampling in compact handheld enclosures.
Recommended
Sensor Signal Acquisition (RTD/Thermistor/Bridge)
The MAX1393ETB+T's true-differential input rejects common-mode noise from industrial sensor wiring (RTDs, strain gauges, load cells) while the integrated 2.5V reference and 312.5 ksps throughput digitize bridge outputs in real time. The differential architecture is essential when sensor leads run near switching power stages, allowing sub-1 LSB noise performance. Designers add an external instrumentation amp (e.g., MAX4475) for thermocouple-grade precision.
Recommended
Handheld Medical and Fitness Monitoring Devices
The MAX1393ETB+T fits handheld pulse oximeters, glucose meters, and fitness wearables where 12-bit resolution is sufficient for heart-rate, SpO2, and bio-impedance signal digitization. Its 1.5V minimum supply runs directly from a single coin cell, while the SPI/QSPI-compatible 3-wire interface connects to low-power MCUs without bus contention. The exposed-pad 10-TDFN package measures 3x3 mm, ideal for wrist-worn form factors.
Recommended
Industrial Process Monitoring (4-20 mA Loop Digitization)
The MAX1393ETB+T digitizes 4-20 mA current-loop signals in industrial process transmitters and remote telemetry units. Its 1.5V to 3.6V supply tolerates loop-drop voltage variations while the true-differential input rejects ground-loop noise from long cable runs. The 12-bit resolution (1.22 mV at 5V reference) gives 0.024% full-scale precision, suitable for process-control loops in factory automation.
Recommended
Consumer Audio and Voice Front-End
The MAX1393ETB+T digitizes microphone pre-amplifier signals in smart speakers, voice remotes, and hearing-aid accessories. Its 312.5 ksps sampling rate captures full 100 kHz audio bandwidth, while the true-differential input rejects common-mode hum from USB and switching-power noise. The micropower shutdown between samples extends battery life in always-listening voice-trigger devices.
Recommended
Remote IoT Sensor Nodes
The MAX1393ETB+T's automatic shutdown and fast wake-up are ideal for LoRaWAN, Zigbee, and BLE IoT sensor nodes that wake periodically to sample and transmit. The 1.5V to 3.6V supply aligns with single-cell Li-ion or 2x AA battery stacks, while the 3-wire SPI interface shares a bus with most low-power MCUs. Each sample cycle draws only microamps, extending multi-year battery life on remote field deployments.
Recommended
Data Logger Front-End (Environmental Monitoring)
The MAX1393ETB+T samples temperature, humidity, pressure, and gas sensors in standalone environmental data loggers with months-to-years battery runtime. Its 312.5 ksps throughput over-samples low-bandwidth sensors for digital filtering, while the 12-bit resolution gives 0.024% full-scale precision for sub-0.1C temperature logging when paired with calibrated thermistors. The compact 10-TDFN package enables pocket-sized form factors.
Recommended
Recommended Products Summary
Engineering reference data for MAX1393ETB+T — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | MAX1393MTB+T | MAX1393ETB+ | MAX1396ETB+T | MAX1396MTB+T |
|---|---|---|---|---|---|
| Brand | Analog Devices / Maxim Integrated | Analog Devices / Maxim Integrated | Analog Devices / Maxim Integrated | Analog Devices / Maxim Integrated | Analog Devices / Maxim Integrated |
| Package | 10-TDFN (3x3) EP | 10-TDFN (3x3) EP - same | 10-TDFN (3x3) EP - same | 10-TDFN (3x3) EP - same | 10-TDFN (3x3) EP - same |
| Resolution | 12 bit | 12 bit | 12 bit | 12 bit | 12 bit |
| Sampling Rate | 312.5 ksps | 312.5 ksps | 312.5 ksps | 312.5 ksps | 312.5 ksps |
| Number of Channels | 1 diff / 2 SE | 1 diff / 2 SE | 1 diff / 2 SE | 2 diff / 4 SE | 2 diff / 4 SE |
| Supply Voltage | 1.5 V to 3.6 V | 1.5 V to 3.6 V | 1.5 V to 3.6 V | 1.5 V to 3.6 V | 1.5 V to 3.6 V |
| Internal Reference | 2.5 V | 2.5 V | 2.5 V | 2.5 V | 2.5 V |
| Automatic Shutdown | Yes | Yes | Yes | Yes | Yes |
Key Differentiators
- True-differential input in a single-channel 10-TDFN ADC (vs MAX1393MTB+T)
- Channel-count flexibility via same-footprint family (vs MAX1396ETB+T)
- Lower throughput floor than higher-speed SARs in same package (vs MAX11164ETC+T)
Design Notes
The MAX1393ETB+T draws supply current in the sub-100 uA range during conversion and drops to a few microamps in automatic shutdown between conversions. Place a 0.1 uF X7R ceramic decoupling capacitor within 3 mm of the VDD pin and a 10 uF bulk capacitor at the board's power input. Decouple AVDD/DVDD if applicable, and tie the exposed pad to a clean analog ground island with multiple vias for thermal and noise performance.
Route the analog input traces as a matched-pair differential microstrip with 50 ohm characteristic impedance and constant coupling. Keep the SCLK/DOUT/CS digital traces away from the analog input pair to avoid digital switching noise coupling into the input. Place a guard ring (grounded trace) around the analog input pins and connect the reference capacitor (typically 0.1 uF) as close to the REF pin as possible for AC performance.
Do not exceed the absolute maximum analog input voltage beyond the supply rails (input ESD diodes will forward-conduct and corrupt the conversion). Always perform a dummy conversion after power-up or after exiting shutdown to flush the internal capacitive DAC, as the first conversion after wake-up may contain residual charge from the track/hold. Reference decoupling with an external capacitor is mandatory when using the internal 2.5 V reference.
The MAX1393ETB+T's true-differential input rejects common-mode noise, but mismatched source impedance (e.g., 1 kΩ on AIN+ and 10 kΩ on AIN-) degrades CMRR. Drive the inputs from a low-impedance source (<= 100 Ω) or buffer with a precision op-amp. Keep the input bandwidth well below the sampling rate (Fs/2 or less) to avoid aliasing; add an external anti-aliasing RC filter before the AIN+/AIN- pins.
Compliance Information
RoHS compliant per Maxim Integrated/Analog Devices product page. Lead-free (Pb-free) per datasheet. Halogen-free status not explicitly stated in the verified data - marked 'unknown'. Not AEC-Q100 qualified - use AEC-Q100-qualified parts for automotive.
