MAX1115EKA+G002 - 8-Bit 100ksps Low-Power ADC | ADI
MPN: MAX1115EKA+G002 ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.85 | $3.85 |
| 10 | $3.47 | $34.70 |
| 100 | $2.98 | $298.00 |
| 500 | $2.55 | $1,275.00 |
| 1,000 | $2.18 | $2,180.00 |
MAX1115EKA+G002 Overview
An ADC (analog-to-digital converter) is an integrated circuit that converts a continuous-time, continuous-amplitude analog voltage into a discrete digital code proportional to the input. SAR (successive-approximation-register) ADCs, which is the architecture used in the MAX1115 family, sample the input once per conversion, run an internal DAC comparison loop, and output the code via a serial interface — offering an excellent trade-off between speed, accuracy, and power for general-purpose data acquisition in the 8-14 bit range. They sit below delta-sigma and pipelined ADCs in resolution but above simple integrating ADCs in speed.
Key features include 8-bit resolution, ±0.5 LSB (typ) DNL/INL, internal 2.048 V reference with external override capability, hardware- or software-controlled shutdown to <1 µA, an on-chip VDD monitor channel, and a serial interface compatible with SPI, QSPI, and MICROWIRE. The internal T/H and dedicated SHDN pin simplify power-sequencing in battery systems where quiescent current directly determines runtime. The 8-pin SOT-23 footprint occupies roughly 9 mm² of board area — about 60% less than an 8-pin SOIC, ideal for space-constrained wearables and portable instrumentation.
Internally, the device uses a charge-redistribution switched-capacitor DAC and a comparator running from an internal oscillator. Conversions complete in under 10 µs; the SCLK-driven serial interface shifts out MSB-first conversion results without an external clock. The integrated reference and VDD monitor reduce external BOM cost by approximately $0.10-$0.20 vs discrete implementations.
Typical applications include portable battery-powered instrumentation, handheld multimeters, loop-powered 4-20 mA sensor transmitters, consumer audio level metering, and isolated industrial sensor front ends where a small, low-power ADC digitizes a slow analog signal before isolation.
When designing with the MAX1115EKA, keep the analog input band-limited well below the Nyquist frequency (50 kHz at 100 ksps), place a 0.1 µF decoupling capacitor within 5 mm of the VDD pin, and bypass REF2 with at least 1 µF for low-noise conversions. The internal reference has a limited drive capability — driving external loads beyond a few µA will degrade linearity.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for MAX1115EKA+G002 — 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 MAX1115EKA+G002 (same form factor and footprint) — differing in Package, Resolution, Supply Voltage, Sampling Rate, Interface.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
MAX1115EKA+T
✅ Drop-In📋 Reference alternative (not in catalog)
MAX1116EKA+T
✅ Drop-In📋 Reference alternative (not in catalog)
MAX1116EKA-T
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$0.78 / Unit
View Datasheet →MAX1115EKA-T
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
MAX1115EKA+T10
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
MAX1115EKA+G002T
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
MAX1116EKA+G002
✅ Drop-In📋 Reference alternative (not in catalog)
MAX1115EKA+G002 Maximum Ratings & Electrical Characteristics
| Resolution | 8 bit |
| Sampling Rate | 100 ksps |
| Number of Channels | 1 |
| Architecture | SAR (Successive Approximation) |
| Supply Voltage Range | +2.7 V to +5.5 V |
| Supply Current (typ at 100 ksps) | 175 µA |
| Shutdown Current | < 1 µA |
| Internal Reference Voltage | +2.048 V |
| Analog Input Range | 0 V to VREF (internal or external) |
| DNL (typ) | ±0.5 LSB |
| INL (typ) | ±0.5 LSB |
| Digital Interface | SPI / QSPI / MICROWIRE compatible |
| Operating Temperature Range | -40 C to +85 C |
| Package | 8-pin SOT-23 (EKA) |
| Mounting Type | Surface Mount |
| MSL Level | 1 |
| RoHS Status | Compliant |
| Lead-Free | Yes |
MAX1115EKA+G002 Pin Configuration
| Pin 1 | AIN — Analog input (0 V to VREF) |
| Pin 2 | GND — Ground |
| Pin 3 | REF — Reference bypass/decoupling (internal +2.048 V or external override) |
| Pin 4 | SHDN — Active-low shutdown (< 1 µA Iq) |
| Pin 5 | DOUT — Serial data output (SPI/QSPI/MICROWIRE) |
| Pin 6 | SCLK — Serial clock input |
| Pin 7 | CS — Active-low chip select |
| Pin 8 | VDD — Positive supply (+2.7 V to +5.5 V) |
Typical Applications
MAX1115EKA+G002 is suitable for 6 applications: Portable Battery-Powered Instrumentation, Loop-Powered 4-20 mA Sensor Transmitters, Handheld Multimeter Digitizer Front End, Consumer Audio VU Meter / Level Indicator, Wearables and Fitness Sensor Readout, Isolated Industrial Sensor Front End.
Portable Battery-Powered Instrumentation
The MAX1115EKA+G002 is purpose-built for handheld battery-powered instruments where its 8-bit 100 ksps SAR ADC and 175 µA supply current directly extend battery runtime. Operates from a single lithium or two-AA cells across +2.7 V to +5.5 V without external level shifters, and the integrated track/hold removes the need for an external buffer at the analog input. In a typical digital multimeter or portable data-logger design, the part digitizes a slow analog sensor at 100 ksps while drawing less than the self-discharge current of an alkaline AA cell. Hardware SHDN drops supply current below 1 µA between conversions, allowing burst-mode operation that further reduces average power to single-digit µA in sleep-dominant duty cycles.
Recommended
Loop-Powered 4-20 mA Sensor Transmitters
The MAX1115EKA+G002 suits 4-20 mA industrial sensor transmitters because its +2.7 V minimum supply voltage fits within the 3.5 mA minimum loop compliance budget after current-setting resistor losses. The internal +2.048 V reference eliminates an external reference IC, and the SPI-compatible serial interface can be galvanically isolated via a digital isolator before the loop transmitter. At 100 ksps the part digitizes a slow thermocouple or RTD signal with 1 LSB = 8 mV resolution — adequate for 1 %-FS industrial sensor readouts. Hardware shutdown below 1 µA helps meet NAMUR NE43 fault-signaling current budgets when the loop controller enters failure mode.
Recommended
Handheld Multimeter Digitizer Front End
In a handheld digital multimeter, the MAX1115EKA+G002 digitizes auto-ranging voltage and current measurements with 8-bit resolution sufficient for the 3.5-digit display segment. The internal +2.048 V reference doubles as a calibration check via the VDD-monitor channel, eliminating a separate supply-monitoring ADC. The 8-pin SOT-23 (EKA) package occupies only ~9 mm² of PCB area — critical for handheld form factors where analog front end, MCU, display, and battery share a small board. SHDN control allows the MCU to power-gate the ADC between range-change operations, extending battery life to several hundred hours on two AA cells.
Recommended
Consumer Audio VU Meter / Level Indicator
The MAX1115EKA+G002 serves as a low-cost audio level digitizer in consumer VU meters, headphone amplifiers, and stereo receivers where 8-bit resolution is sufficient for bar-graph level display. Its 100 ksps sampling rate captures audio envelopes well above the audible band, and the integrated track/hold converts bursty audio peaks without external anti-alias filtering beyond a simple RC network. The SOT-23 footprint saves board space in compact audio dongles. With only 175 µA supply current the part adds negligible load to USB-powered headphone amps — preserving battery life for the active audio stages.
Recommended
Wearables and Fitness Sensor Readout
Wearable fitness bands and smartwatches leverage the MAX1115EKA+G002 to digitize optical heart-rate, skin-temperature, and battery-voltage telemetry signals with minimal current drain. The +2.7 V minimum supply rail works directly from a single Li-ion cell, and the <1 µA hardware-shutdown current allows the MCU to power-cycle the ADC between sensor reads for average current below 5 µA — critical for week-long battery-life targets. The integrated VDD-monitor channel replaces a discrete voltage divider for battery-fuel gauging, saving board area on a tight 1.4-inch diameter wearable PCB.
Recommended
Isolated Industrial Sensor Front End
In an isolated industrial sensor module — such as a PLC analog input, a motor-drive phase-current monitor, or a process-control transmitter — the MAX1115EKA+G002 digitizes a low-bandwidth analog signal before the isolation barrier. Its SPI-compatible serial interface is readily bridged by a digital isolator or opto-isolator, allowing the high-voltage field side and the low-voltage logic side to communicate across 5 kVRMS isolation. The 100 ksps sampling rate supports typical 4 kHz process-control bandwidths (well above the Nyquist limit), and the 175 µA supply current stays within the energy-harvesting or auxiliary-supply budget of an isolated front-end module.
Recommended
Recommended Products Summary
Engineering reference data for MAX1115EKA+G002 — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | MAX1115EKA+T | MAX1116EKA+T | MAX1115EKA+G002T |
|---|---|---|---|---|
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices |
| Package | 8-pin SOT-23 (EKA) | 8-pin SOT-23 (EKA) - same | 8-pin SOT-23 (EKA) - same | 8-pin SOT-23 (EKA) - same |
| Resolution | 8 bit | 8 bit | 8 bit | 8 bit |
| Sampling Rate | 100 ksps | 100 ksps | 100 ksps | 100 ksps |
| Supply Voltage Range | +2.7 V to +5.5 V | +2.7 V to +5.5 V | +4.5 V to +5.5 V | +2.7 V to +5.5 V |
| Supply Current (100 ksps) | 175 µA | 175 µA | 175 µA | 175 µA |
| Internal Reference | +2.048 V | +2.048 V | +2.048 V | +2.048 V |
| Serial Interface | SPI / QSPI / MICROWIRE | SPI / QSPI / MICROWIRE | SPI / QSPI / MICROWIRE | SPI / QSPI / MICROWIRE |
| Operating Temperature | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C |
Key Differentiators
- Lowest supply current 8-bit SAR ADC in SOT-23 (vs MAX1116EKA+T)
- Integrated VDD monitor channel replaces a discrete supply supervisor (vs MAX1115EKA+T)
- Hardware SHDN below 1 µA extends battery runtime in sleep-dominant duty cycles (vs MAX1115EKA+G002T)
Design Notes
Place a 0.1 µF X7R ceramic decoupling capacitor within 5 mm of the VDD pin (pin 8) and a 10 µF bulk capacitor on the same rail. The internal +2.048 V reference should be bypassed with at least 1 µF X7R at the REF pin (pin 3) to minimize conversion-to-conversion noise. Do not draw more than a few µA from the REF pin — driving external loads will degrade DNL and INL linearity. Estimated: a 1 µF REF bypass holds droop under 5 mV during a 100 ksps conversion burst, well within the ±0.5 LSB linearity budget at 8 mV/LSB.
Route AIN (pin 1) as a short, guarded trace with a ground keep-out island on either side. Avoid routing digital SPI signals (SCLK, DOUT, CS) parallel to AIN for more than 5 mm to prevent capacitive coupling of digital edges into the analog input. Tie SGT high through a 100 kΩ resistor if hardware shutdown is not used. Keep the VDD trace wide enough to handle the 175 µA peak inrush during each conversion — a 0.5 mm trace is more than sufficient.
Do not drive AIN above VREF or below GND — the input track/hold will forward-bias the ESD diodes and inject distortion or damage the cell. Do not enable the MAX1115 (vs MAX1116) on a 5 V supply and expect MAX1116 behavior — the MAX1116 has tighter noise specs at 5 V but operates only above +4.5 V. When reading the VDD-monitor channel, account for the internal reference being rati-on-unpowered (VDD falls below +2.7 V); the monitor channel gives a proportional code only when VDD is within the operating range.
Source-impedance at AIN should be kept below 5 kΩ to avoid conversion errors from the track/hold acquisition-time budget. The MAX1115 acquisition time is approximately 400 ns; a 5 kΩ source driving the 16 pF internal sampling capacitor settles within ~2 LSB at full speed. For higher source impedances, add an external op-amp buffer such as the MAX4475 or a similar low-noise CMOS amplifier. Estimated: at 100 ksps with 5 kΩ source, the settling error is < 1 LSB.
Compliance Information
RoHS-compliant lead-free variant (G002 suffix per Maxim legacy ordering code). Industrial temperature grade -40 C to +85 C. Not AEC-Q100 qualified; for automotive applications, select a MAX1115xTQ Automotive grade or equivalent. Halogen-free status not explicitly documented in retrieved data — marked unknown.
