MAX1116EKA-T - 8-Bit 100kSPS SAR ADC SOT-23-8 | Maxim Integrated
MPN: MAX1116EKA-T ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.42 | $1.42 |
| 10 | $1.27 | $12.70 |
| 100 | $1.08 | $108.00 |
| 500 | $0.92 | $460.00 |
| 1,000 | $0.78 | $780.00 |
MAX1116EKA-T Overview
A successive-approximation ADC is a type of data converter that uses a binary-search algorithm against an internal precision DAC to digitize an analog input in N clock cycles for N bits of resolution. SAR ADCs are prized for their deterministic latency, single-shot conversion capability, and absence of pipeline delay, making them the architecture of choice for multiplexed data-acquisition systems, sensor front-ends, and process-control loops where deterministic timing is required.
Key features include 8-bit resolution with no missing codes, an internal 2.048 V reference, an analog input range of 0 V to VREF (unipolar), a high-impedance analog input, and a hardware-/software-programmable power-down mode that drops quiescent current to <1 µA between conversions for battery-powered duty-cycled applications.
The MAX1116EKA-T uses Maxim's low-leakage CMOS SAR core with an internal charge-redistribution DAC and on-chip bandgap reference, eliminating the need for external reference components in cost-sensitive designs. The serial interface supports SPI, QSPI, and MICROWIRE hosts, allowing direct connection to most modern microcontrollers and DSPs without glue logic.
Typical applications include 4 mA to 20 mA loop-powered remote data-acquisition systems, battery-powered test equipment, low-power handheld portable devices, receive signal-strength indicators (RSSI) in radios, and general system-diagnostics monitoring. The wide operating temperature range of -40 °C to +85 °C makes it suitable for industrial-grade portable instruments. Provide a high-side LDO to power the converter when used on a 4 mA to 20 mA loop.
When designing with this part, place a 10 nF bypass capacitor as close as possible to VDD to keep digital switching noise out of the reference, and ensure the analog input source bandwidth matches the acquisition time (typically 625 ns at 100 kSPS) to avoid code-edge errors. The reference decoupling must be sized for the conversion clock; see the datasheet typical application circuit.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet alone.
Drop-in alternatives for MAX1116EKA-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 MAX1116EKA-T (same form factor and footprint) — differing in Analog Input Range, Package, Resolution.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
MAX1116EKA+T
✅ Drop-In📋 Reference alternative (not in catalog)
MAX1115EKA-T
✅ Drop-In📋 Reference alternative (not in catalog)
MAX1115EKA+G002
✅ Drop-In✓ In Stock
$2.18 / Unit
View Datasheet →MAX1116EKA+T10
✅ Drop-In📋 Reference alternative (not in catalog)
MAX1116EKA
✅ Drop-In📋 Reference alternative (not in catalog)
MAX1116EKA-T Maximum Ratings & Electrical Characteristics
| Resolution | 8 bits |
| Number of Inputs | 1 (single-ended) |
| Sampling Rate | 100 kSPS |
| Architecture | SAR (Successive Approximation) |
| Supply Voltage | 4.5 V to 5.5 V |
| Supply Current | 175 µA at 100 kSPS |
| Power-Down Current | <1 µA |
| Analog Input Range | 0 V to VREF (unipolar) |
| Internal Reference | 2.048 V |
| Data Interface | SPI, QSPI, MICROWIRE-compatible serial |
| Package | SOT-23-8 |
| Operating Temperature | -40 °C to +85 °C |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
| Package Footprint | ~30% of an 8-pin SO |
MAX1116EKA-T Pin Configuration
| Pin 1 | AIN — Analog input (0 V to VREF) |
| Pin 2 | GND — Ground |
| Pin 3 | CS — Chip-select (active-low) |
| Pin 4 | DOUT — Serial data output |
| Pin 5 | DIN — Serial data input |
| Pin 6 | SCLK — Serial clock input |
| Pin 7 | REF — Reference decoupling (internal 2.048 V) |
| Pin 8 | VDD — Power supply (+4.5 V to +5.5 V) |
Typical Applications
MAX1116EKA-T is suitable for 6 applications: 4-20 mA Loop-Powered Data Acquisition, Battery-Powered Test Equipment, Receive Signal-Strength Indicator (RSSI), System Diagnostics and Fault Monitoring, Handheld Portable Sensor Reading, Industrial Front-End Module.
4-20 mA Loop-Powered Data Acquisition
The MAX1116EKA-T is well-suited to 4-20 mA loop-powered data acquisition because of its 175 µA supply current at 100 kSPS and <1 µA power-down current between conversions, which fits within the residual budget of a typical 4-20 mA loop after the loop-powered sensor. Its 8-bit resolution (one LSB = 8 mV with the internal 2.048 V reference) is adequate for industrial process variables like temperature, pressure, and flow-rate telemetry. The integrated 2.048 V reference eliminates the need for external reference components, reducing total BOM cost in remote sensor nodes. Compared to a sigma-delta ADC, the SAR architecture provides deterministic single-cycle conversion latency, which simplifies loop-response timing. Place a 10 nF bypass capacitor at the VDD pin and add ESD protection at the analog input.
Recommended
Battery-Powered Test Equipment
The MAX1116EKA-T's 175 µA active supply current and <1 µA power-down mode make it attractive for handheld battery-powered test equipment that must digitize analog signals at low duty cycle. The hardware-/software-programmable power-down lets the host microcontroller shut the ADC down between samples, extending battery runtime by orders of magnitude. Its small SOT-23-8 footprint (~30% of an 8-pin SO) saves board space in compact handheld housings. The SPI-compatible serial interface allows direct connection to low-power microcontrollers such as the MAX32U2 in this same voltage range. With -40 °C to +85 °C operation, the part works in field and lab environments. Add a Schottky reverse-polarity protection diode at the battery terminal for handheld robustness.
Recommended
Receive Signal-Strength Indicator (RSSI)
The MAX1116EKA-T is well-suited as an RSSI digitizer in sub-GHz radio front-ends, where it converts an analog RSSI voltage from the receiver IF chain into an 8-bit digital value for the host MCU. Its 100 kSPS sampling rate is more than adequate for the slow-changing RSSI levels produced by RF AGC loops, and its SAR architecture avoids the group-delay artifacts that pipeline ADCs introduce. The single-ended analog input accepts 0 V to VREF and can be tied directly to the receiver's RSSI op-amp output. The 2.048 V internal reference gives an 8 mV LSB, which provides ~1 dB of RSSI resolution when paired with a typical 60 mV/dB log-amp slope. Add a small RC filter at AIN to clean IF ripple.
Recommended
System Diagnostics and Fault Monitoring
The MAX1116EKA-T is a strong fit for system-diagnostics and fault-monitoring designs where many analog rails need periodic digitization at low cost and small footprint. Its on-chip reference, track-and-hold, and SPI interface let an MCU poll several rails through an external analog mux without external signal-conditioning components. The deterministic SAR latency simplifies fault-timing analysis in safety-critical firmware. The 8-bit resolution is adequate for monitoring supply rails (12 V, 5 V, 3.3 V) via resistive dividers, current-sensor outputs, and temperature sensors. With a -40 °C to +85 °C operating range, the part is industrial-grade. Add a TVS at AIN and route the analog trace away from switching nodes.
Recommended
Handheld Portable Sensor Reading
The MAX1116EKA-T is ideal for handheld portable sensor-reading applications such as spot meters, environmental sensors, and handheld gas detectors where low cost, small package, and low power are all critical. The SOT-23-8 footprint (~30% of an 8-pin SO) reduces PCB area, and the <1 µA power-down current lets the ADC idle for the majority of the battery's life while a sample is taken once every few seconds. The 8-bit output is sufficient for display-driving and threshold-detection tasks typical of portable instruments. The integrated 2.048 V reference avoids adding cost in BOM-constrained designs. Compared to an external ADC + reference solution, the integrated reference saves 2-4 mm² in typical layouts.
Recommended
Industrial Front-End Module
The MAX1116EKA-T is well-suited to industrial front-end modules that aggregate analog sensor signals (temperature, pressure, level, position) into a digital bus for a downstream PLC or controller. Its SPI/QSPI/MICROWIRE-compatible serial interface supports direct connection to most industrial-grade microcontrollers and DSPs, eliminating the need for glue logic. The SAR core's deterministic latency simplifies synchronization in multi-channel time-multiplexed designs. The on-chip VDD monitor and internal reference cut down the analog BOM, and the small SOT-23-8 footprint lets the ADC sit on the same board as an MUX for up to 8 inputs. The -40 °C to +85 °C operating range meets industrial temperature requirements. Add isolation barriers for high-voltage industrial interfaces.
Recommended
Recommended Products Summary
Engineering reference data for MAX1116EKA-T — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | MAX1116EKA+T | MAX1115EKA-T | MAX1115EKA+G002 | MAX1116EKA+T10 | MAX1116EKA |
|---|---|---|---|---|---|---|
| Package | SOT-23-8 | SOT-23-8 - same | SOT-23-8 - same | SOT-23-8 - same | SOT-23-8 - same | SOT-23-8 - same |
| Brand | Analog Devices (Maxim Integrated) | Analog Devices - same | Analog Devices - same | Analog Devices - same | Analog Devices - same | Analog Devices - same |
| Resolution | 8 bit | 8 bit | 8 bit | 8 bit | 8 bit | 8 bit |
| Sampling Rate | 100 kSPS | 100 kSPS | 100 kSPS | 100 kSPS | 100 kSPS | 100 kSPS |
| Supply Voltage | 4.5 V to 5.5 V | 4.5 V to 5.5 V | 2.7 V to 5.5 V | 2.7 V to 5.5 V | 4.5 V to 5.5 V | 4.5 V to 5.5 V |
| Supply Current | 175 µA | 175 µA | 175 µA | 175 µA | 175 µA | 175 µA |
| Internal Reference | 2.048 V | 2.048 V | 2.048 V | 2.048 V | 2.048 V | 2.048 V |
| Operating Temperature | -40 °C to +85 °C | -40 °C to +85 °C | -40 °C to +85 °C | -40 °C to +85 °C | -40 °C to +85 °C | -40 °C to +85 °C |
Key Differentiators
- Integrated 2.048 V reference eliminates external reference cost (vs MAX1115EKA-T)
- Optimized for +5 V supply systems (vs MAX1115EKA-T)
- SAR architecture provides deterministic single-cycle latency (vs Generic sigma-delta ADC)
Design Notes
Place a 10 nF ceramic bypass capacitor as close as possible to the VDD pin (pin 8) to keep digital switching noise out of the internal reference. A larger bulk capacitor (1 µF to 10 µF) on the same VDD trace further suppresses low-frequency ripple. Decouple the REF pin (pin 7) with a 1 µF to 10 µF ceramic to prevent reference transients from coupling into the analog input during the track-and-hold acquisition.
Route the analog input (AIN, pin 1) trace away from the serial clock (pin 6) and serial data lines (pins 4 and 5) to minimize digital-to-analog crosstalk. Use a guarded ground pattern around the analog input node and place the device close to the analog signal source to reduce the input track length and pickup.
Do not exceed the absolute-maximum analog input of VDD + 5 mV; otherwise the ESD diode will forward-bias and degrade linearity. Ensure the host MCU configures the SCLK frequency to be within the datasheet-specified range for the chosen supply voltage; an out-of-spec SCLK will violate the acquisition time and cause missing codes.
The internal track-and-hold acquires the analog input in 625 ns at 100 kSPS. Estimated: the analog signal source bandwidth should be at least 1.6 MHz so that the source settles within the acquisition window with <1 LSB of error. Add an RC buffer at AIN when sampling high-impedance sources.
Compliance Information
RoHS-compliant per Maxim/Analog Devices product page. Not AEC-Q100 qualified (industrial temperature range only). Lead-free and halogen-free per DigiKey/Mouser listings.
