MAX1115EKA+G002 - 8-Bit 100ksps Low-Power ADC | ADI
MPN: MAX1115EKA+G002 ✓ Hoạt độngMAX1115EKA+G002 Tóm tắt
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.
Bộ thay thế dễ dàng lắp đặt cho MAX1115EKA+G002 — cùng gói, chân-to-chân tương thích. Các bộ phận yêu cầu hàn PCB bị loại trừ.
Các biến thể trong loạt này
Các mẫu cùng loạt có thể lắp đặt dễ dàng tương thích với MAX1115EKA+G002 (cùng hình factor và footprint) — khác nhau ở Package, Resolution, Supply Voltage, Sampling Rate, Interface.
MAX1115EKA+T
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
MAX1116EKA+T
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
MAX1116EKA-T
✅ Drop-In ⚠️ Thông số chưa được xác minhLiên hệ để biết giá
Xem tài liệu →MAX1115EKA-T
✅ Drop-In ⚠️ Thông số chưa được xác minh📋 Tham chiếu thay thế (không có trong danh mục)
MAX1115EKA+T10
✅ Drop-In ⚠️ Thông số chưa được xác minh📋 Tham chiếu thay thế (không có trong danh mục)
MAX1115EKA+G002T
✅ Drop-In ⚠️ Thông số chưa được xác minh📋 Tham chiếu thay thế (không có trong danh mục)
MAX1116EKA+G002
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
MAX1115EKA+G002 Tỷ lệ tối đa & tính chất điện
| Độ phân giải | 8 bit |
| Tỷ lệ lấy mẫu | 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 |
| Điện áp tắt | < 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 |
| Khoảng nhiệt độ hoạt động | -40 C to +85 C |
| Hộp | 8-pin SOT-23 (EKA) |
| Kiểu lắp đặt | Surface Mount |
| Cấp MSL | 1 |
| Trạng thái RoHS | Compliant |
| Lead-Free | Yes |
Cấu hình chân MAX1115EKA+G002
| Chân 1 | AIN — Analog input (0 V to VREF) |
| Chân 2 | GND — Ground |
| Chân 3 | REF — Reference bypass/decoupling (internal +2.048 V or external override) |
| Chân 4 | SHDN — Active-low shutdown (< 1 µA Iq) |
| Chân 5 | DOUT — Serial data output (SPI/QSPI/MICROWIRE) |
| Chân 6 | SCLK — Serial clock input |
| Chân 7 | CS — Active-low chip select |
| Chân 8 | VDD — Positive supply (+2.7 V to +5.5 V) |
Ứng dụng tiêu biểu
MAX1115EKA+G002 phù hợp cho 6 Áp dụngs: 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.
Được đề xuất
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.
Được đề xuất
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.
Được đề xuất
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.
Được đề xuất
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.
Được đề xuất
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.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho MAX1115EKA+G002 — so sánh, hướng dẫn thiết kế và thông tin tuân thủ.
Hướng dẫn chọn lựa
So sánh với các sản phẩm thay thế
| Tham số | Sản phẩm này | 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 |
Bảo phân biệt quan trọng
- Lowest supply current 8-bit SAR ADC in SOT-23 (vsMAX1116EKA+T)
- Integrated VDD monitor channel replaces a discrete supply supervisor (vsMAX1115EKA+T)
- Hardware SHDN below 1 µA extends battery runtime in sleep-dominant duty cycles (vsMAX1115EKA+G002T)
Ghi chú thiết kế
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.
Thông tin tuân thủ
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.
