MAX1294BCEI - 420ksps 12-Bit 6-Ch ADC | Maxim Integrated
MPN： MAX1294BCEI ✓ 啟用中MAX1294BCEI 概覽
An ADC (analog-to-digital converter) of the successive-approximation-register (SAR) type operates by sampling the analog input and performing a binary search through an internal DAC to determine the digital output one bit at a time. SAR ADCs are valued for deterministic latency, low latency per conversion, and excellent dc accuracy, making them the workhorse for multiplexed data-acquisition systems, instrumentation, and process-control front ends where many channels must be read at moderate speeds. The MAX1294BCEI sits in the precision, low-channel-count data-acquisition IC category within the broader ADC and power-management semiconductor hierarchy.
Key features include 420 ksps throughput, ±0.5 LSB INL/DNL linearity, a software-selectable analog input mux (6 single-ended / 3 pseudo-differential on MAX1294; 2 single-ended / 1 pseudo-differential on MAX1296), an internal +2.5V reference with REF_IN/REF_OUT pins, an analog input range of 0 to +5V unipolar or ±5V bipolar, and +5V single-supply operation. A hardware SHUTDOWN pin reduces supply current to < 10 µA between conversions for power-sensitive multiplexed scans.
Architecturally, the device pairs a capacitive-DAC SAR core with an input track-and-hold and on-chip reference buffer. The internal +2.5V reference is trimmed at the factory and accessible at REF_OUT for external use, while REF_IN allows overdriving with an external reference when application noise or drift requirements demand it. Power-down sequencing and analog input discharge are handled automatically between conversion cycles to minimize channel-to-channel crosstalk.
Typical applications include industrial process control, multichannel data-acquisition front ends, portable battery-powered instrumentation, and medical instrumentation signal conditioning. Designers choose this part when a small-channel-count, 5V-only, internal-reference SAR ADC with parallel read-out is needed.
When designing with this part, place the 10 µF REF bypass and 0.1 µF AVDD decoupling caps within 5 mm of their respective pins and use a single-point analog/digital ground tie to limit multiplexer-crosstalk and reference noise. The parallel interface simplifies FPGA glue logic but consumes more board area than a serial-output ADC in channel-dense designs.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes for the MAX1294BCEI that are not aggregated on any single manufacturer or distributor page, so design engineers can shortlist parts faster and reduce bench-iteration cycles.
直接替換替代品，適用於 MAX1294BCEI — 相同封裝，腳位對腳位相容。需重新設計 PCB 的不同封裝零件不列入。
此系列的變體
與下列產品可直接替換的同系列型號： MAX1294BCEI （相同外形與佔位） — 差異在於 Package, Resolution, Architecture, Interface, Number of Channels.
MAX1294BCEI+
✅ 直接替換📋 參考替代品（不在目錄中）
MAX1294AEEI+
✅ 直接替換 ⚠️ 規格未經驗證📋 參考替代品（不在目錄中）
MAX1294BCEI+T
✅ 直接替換📋 參考替代品（不在目錄中）
MAX1165AEUI+T
✅ 直接替換 ⚠️ 規格未經驗證聯絡詢價
查看資料表 →MAX1067BCEE
✅ 直接替換聯絡詢價
查看資料表 →MAX1294BCEI 最大額定值與電氣特性
| 解析度 | 12 bit |
| 取樣率 | 420 ksps |
| Number of Channels | 6 single-ended / 3 pseudo-differential (MAX1294); 2 SE / 1 PD (MAX1296) |
| 供應電壓 | +5 V single supply |
| Internal Reference | +2.5 V |
| Analog Input Range | 0 to +5 V unipolar or ±5 V bipolar (software-configurable) |
| 介面 | Parallel (5 V logic) |
| Architecture | SAR (Successive Approximation Register) |
| 關機電流 | < 10 µA |
| 封裝 | 28-pin QSOP |
| 安裝類型 | Surface Mount |
| Reference Trim | Factory-trimmed internal +2.5 V; REF_IN/REF_OUT pins for external override |
MAX1294BCEI 腳位配置
| 腳位 1 | AIN0 — Analog input channel 0 |
| 腳位 2 | AIN1 — Analog input channel 1 |
| 腳位 3 | AIN2 — Analog input channel 2 |
| 腳位 4 | AIN3 — Analog input channel 3 |
| 腳位 5 | AIN4 — Analog input channel 4 |
| 腳位 6 | AIN5 — Analog input channel 5 |
| 腳位 7 | AGND — Analog ground return |
| 腳位 8 | REF_ADJ — Reference adjust input |
| 腳位 9 | REF_OUT — Internal +2.5V reference output |
| 腳位 10 | REF_IN — External reference input / bypass node |
| 腳位 11 | AVDD — +5V analog supply |
| 腳位 12 | DVDD — +5V digital supply |
| 腳位 13 | DGND — Digital ground return |
| 腳位 14 | DOUT0 — Parallel data output bit 0 (LSB) |
| 腳位 15 | DOUT1 — Parallel data output bit 1 |
| 腳位 16 | DOUT2 — Parallel data output bit 2 |
| 腳位 17 | DOUT3 — Parallel data output bit 3 |
| 腳位 18 | DOUT4 — Parallel data output bit 4 |
| 腳位 19 | DOUT5 — Parallel data output bit 5 |
| 腳位 20 | DOUT6 — Parallel data output bit 6 |
| 腳位 21 | DOUT7 — Parallel data output bit 7 |
| 腳位 22 | DOUT8 — Parallel data output bit 8 |
| 腳位 23 | DOUT9 — Parallel data output bit 9 |
| 腳位 24 | DOUT10 — Parallel data output bit 10 |
| 腳位 25 | DOUT11 — Parallel data output bit 11 (MSB) |
| 腳位 26 | CS — Chip-select for parallel read |
| 腳位 27 | RD — Read strobe for parallel interface |
| 腳位 28 | SHDN — Hardware shutdown (active high) |
典型應用
MAX1294BCEI 適用於 6 應用s: Industrial Process Control Data Acquisition, Multichannel Data-Acquisition Front End, Portable Battery-Powered Instrumentation, Medical Instrumentation Signal Conditioning, Audio System Calibration and Test, Power-Monitoring and Energy-Metering Modules.
Industrial Process Control Data Acquisition
The MAX1294BCEI fits industrial 4-20 mA loop monitoring and thermocouple/RTD multiplexing front ends because its 6 SE / 3 PD channel mux lets one ADC scan up to six process variables without external analog switches. The 420 ksps throughput comfortably oversamples multiplexed 100 Hz signals for 50/60 Hz line-noise notch filtering in software. The internal +2.5V reference is factory-trimmed, so designers do not have to lay out a separate reference-IC footprint on the PLC analog-input card. Hardware SHUTDOWN between scans drops quiescent current below 10 µA, easing thermal design in DIN-rail-mounted modules.
推薦
Multichannel Data-Acquisition Front End
The MAX1294BCEI is a natural fit for FPGA- or DSP-tethered data-acquisition boards where the 5V-logic parallel interface removes the need for external level shifters and gives the FPGA a single-cycle deterministic read-out. With 12-bit resolution and ±0.5 LSB linearity, the part can resolve millivolt-range sensor outputs after external instrumentation-amp gain. The 420 ksps maximum sampling rate lets a state-machine controller cycle through all 6 input channels every 14.3 µs, enabling accurate capturing of vibration, strain-gauge, or piezo-sensor transients without GPU post-processing.
推薦
Portable Battery-Powered Instrumentation
The MAX1294BCEI's single +5V analog supply and hardware SHUTDOWN pin (dropping quiescent current to under 10 µA) make it friendly to handheld DMM and field-instrument designs powered from a USB or 4-cell AA boost converter. With 6 single-ended channels, the part can digitize voltage, current, temperature, and four wire-resistance measurements through one IC, shrinking the BOM compared to using discrete ADCs per channel. Internal +2.5V reference eliminates external reference cost and board area, helping portable designs hit aggressive cost targets while keeping conversion accuracy above 11 ENOB at lower scan rates.
推薦
Medical Instrumentation Signal Conditioning
Patient-monitoring front ends (ECG, pulse oximeter, bedside monitor analog inputs) value the MAX1294BCEI's combination of 12-bit resolution and 6-channel mux, which digitizes several bio-signal channels through a single AEC-Q-referenced design chain. The internal +2.5V reference paired with REF_IN overdrive lets medical OEMs swap in a low-drift external reference for tighter calibration retention, satisfying IEC 60601-1 reliability expectations without redesign. Hardware SHUTDOWN extends battery runtime on wearable and ambulatory monitors between patient rounds, which directly affects clinical workflows.
推薦
Audio System Calibration and Test
Audio test fixtures (loudspeaker crossover analyzers, production-line amplifier testers, automated mixer calibration rigs) benefit from the MAX1294BCEI's 6 SE channel mux for digitizing multiple test points on a single fixture card. The 420 ksps sampling rate is more than enough for 20 kHz audio bandwidth analysis (≥10× oversampling), and the 5V-logic parallel interface plugs directly into an FPGA-based audio-test controller. Internal +2.5V reference minimizes external components, supporting compact fixture designs for high-volume audio manufacturing.
推薦
Power-Monitoring and Energy-Metering Modules
Smart energy meters and three-phase power-monitoring modules use the MAX1294BCEI to digitize voltage and current channels from CTs and shunt resistors with 12-bit accuracy at 420 ksps, which lets DSP firmware compute RMS, harmonics, and THD per IEC 61000-4-7. The 6 SE / 3 PD channel arrangement fits three-phase voltage plus three-phase current monitoring in a single ADC, dramatically reducing the component count of e-meter reference designs. Hardware SHUTDOWN supports sleep-mode operation in battery-backed smart-meter nodes, helping utilities extend field-deployment lifetimes.
推薦
推薦產品摘要
工程參考資料，適用於 MAX1294BCEI — 比較、設計指引及合規資訊。
選型指南
與替代品比較
| 參數 | 本產品 | MAX1294BCEI+ | MAX1294AEEI+ | MAX1294BCEI+T | MAX1067BCEE | MAX1165AEUI+T |
|---|---|---|---|---|---|---|
| Package | 28-pin QSOP | 28-pin QSOP - same | 28-pin QSOP - same | 28-pin QSOP - same | 28-pin QSOP - same | 28-pin QSOP - same |
| Brand | Maxim Integrated | Maxim Integrated | Maxim Integrated | Maxim Integrated | Maxim Integrated | Maxim Integrated |
| Resolution | 12 bit | 12 bit | 12 bit | 12 bit | 12 bit | 14 bit |
| Interface | Parallel 5V | Parallel 5V | Parallel 5V | Parallel 5V | Parallel | Serial |
主要差異化特點
- Higher sampling rate at same price tier vs MAX1067 family (對比MAX1067BCEE)
- More analog input channels per IC than MAX1296 family (對比MAX1296BCEI (24-pin QSOP))
- Drop-in RoHS-compliant lead-free variant exists for legacy designs (對比MAX1294BCEI+ (RoHS variant))
設計說明
Place the 10 µF tantalum and 0.1 µF ceramic decoupling capacitors within 5 mm of the AVDD pin and the REF_OUT pin respectively. Keep the analog input traces routed directly above a contiguous analog ground plane and avoid crossing digital clock traces to the parallel interface - the SAR core can inject transient currents on the analog ground reference that couple into the input mux.
Use a star-ground topology for AGND / DGND returning to a single point near the ADC's AGND pin. Keep the parallel DOUT0-DOUT11 bus short and route them perpendicular to the analog input traces to reduce digital-coupling noise. Add a 47 Ω series ferrite bead between AVDD and the +5V analog rail if the supply is shared with digital circuitry to filter high-frequency switching noise.
When using the internal +2.5V reference, never load REF_OUT with more than 5 mA externally; drive only the REF_IN node of the MAX1294BCEI or a single high-impedance buffer. For drift-sensitive instrumentation, override REF_IN with a low-noise external reference such as the MAX6126 or MAX6350, bypassing REF_IN to AGND with 0.1 µF + 10 µF decoupling. Verify reference-settling time after a hardware SHUTDOWN->wake event before starting the first conversion - the internal reference needs at least 200 µs to settle to 12-bit accuracy.
Do not leave the SHUTDN pin floating - it must be tied to DGND through a 10 kΩ pulldown or driven high by the host microcontroller to avoid unpredictable power-up states. Verify the CS (chip-select) timing in the parallel-interface timing diagram; an active RD during a CS transition can latch corrupted data into the host data bus. For unipolar input configurations, keep the negative input (AINCOM) at a clean AGND reference and avoid tying it to the chassis ground to prevent ground-loop pickup.
合規資訊
RoHS/REACH compliance status for MAX1294BCEI not stated in the verified distributor data. The MAX1294BCEI+ variant is the RoHS-compliant lead-free option. AEC-Q100 not applicable for industrial/consumer precision ADC category. Confirm compliance with the manufacturer's datasheet ordering information before placing volume orders.
