MAX1228ACEP+T - 12-Bit 300ksps ADC w/ FIFO & Temp Sensor | Maxim
MPN： MAX1228ACEP+T ✓ 啟用中MAX1228ACEP+T 概覽
An SAR ADC is a type of analog-to-digital converter that uses a charge-redistribution DAC and a comparator to resolve one bit per clock cycle, achieving deterministic latency and low pipeline delay. Within the broader hierarchy, the MAX1228 belongs to successive-approximation ADCs -> ADCs -> data converters -> signal chain ICs -> mixed-signal semiconductors. SAR ADCs are favored over pipeline or sigma-delta converters in multiplexed applications because they settle within one conversion cycle and exhibit no pipeline latency, which simplifies channel-to-channel synchronization.
Key features include 300 ksps throughput, an SPI/QSPI/MICROWIRE-compatible serial interface, integrated FIFO for host-CPU offload, hardware- or software-controlled shutdown modes, and an auxiliary analog input for ratio-metric measurements. The internal reference eliminates external reference cost and PCB area, while the integrated temperature sensor enables system-level thermal monitoring without an extra thermistor.
Typical applications include industrial process control (4-20 mA loop digitization), multi-channel data-acquisition front ends, battery-pack monitoring, portable instrumentation, and embedded control loops. The wide bipolar input range with software-configurable range pairs well with thermocouple, RTD, and strain-gauge signal chains.
Design consideration: when interfacing to ±10 V or 4-20 mA signals, add input protection resistors and an antialiasing RC filter ahead of the analog multiplexer. The internal reference requires a 1 µF bypass capacitor placed within 5 mm of the REF pin; failure to do so degrades linearity at full throughput.
This page synthesizes cross-brand drop-in alternatives, parametric comparison, and practical design notes not found in the manufacturer datasheet alone.
直接替換替代品，適用於 MAX1228ACEP+T — 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： MAX1228ACEP+T （相同外形與佔位） — 差異在於 Mounting Type, Resolution, Analog Supply Voltage, Package, RoHS Status.
MAX1228ACEP+
✅ 直接替換聯絡詢價
查看資料表 →MAX1228BCEP+
✅ 直接替換📋 參考替代品（不在目錄中）
MAX1228BEEP+
✅ 直接替換📋 參考替代品（不在目錄中）
MAX1226CEP+
✅ 直接替換📋 參考替代品（不在目錄中）
MAX1230CEP+
✅ 直接替換📋 參考替代品（不在目錄中）
MAX1202ACAP
✅ 直接替換聯絡詢價
查看資料表 →MAX1228ACEP+T 最大額定值與電氣特性
| 解析度 | 12 bit |
| 取樣率 | 300 ksps |
| Architecture | SAR (Successive Approximation) |
| Number of Inputs | 6 / 12 (single-ended, software-configurable) |
| Input Type | Single-Ended, True Bipolar |
| Analog Input Range | -12 V to +12 V (software-configurable) |
| Internal Reference Voltage | 4.096 V |
| Internal Temperature Sensor Accuracy | ±1 °C |
| FIFO Buffer | 16 entries |
| 介面 | SPI / QSPI / MICROWIRE-compatible serial |
| 封裝 | 20-QSOP (SSOP, 0.154", 3.90 mm width) |
| 工作溫度範圍 | 0 °C to +70 °C (commercial grade, ACE suffix) |
| Temperature Grade | Commercial |
| Terminal Form | Gull Wing |
| 安裝類型 | Surface Mount |
| RoHS 狀態 | Compliant |
MAX1228ACEP+T 腳位配置
| 腳位 1 | AGND — Analog ground |
| 腳位 2 | AIN0 — Analog input 0 |
| 腳位 3 | AIN1 — Analog input 1 |
| 腳位 4 | AIN2 — Analog input 2 |
| 腳位 5 | AIN3 — Analog input 3 |
| 腳位 6 | AIN4 — Analog input 4 |
| 腳位 7 | AIN5 — Analog input 5 |
| 腳位 8 | AIN6 — Analog input 6 |
| 腳位 9 | AIN7 — Analog input 7 |
| 腳位 10 | AIN8 — Analog input 8 |
| 腳位 11 | AIN9 — Analog input 9 |
| 腳位 12 | AIN10 — Analog input 10 |
| 腳位 13 | AIN11 — Analog input 11 |
| 腳位 14 | REF — Internal 4.096 V reference (bypass with 1 µF) |
| 腳位 15 | DGND — Digital ground |
| 腳位 16 | DOUT — Serial data output |
| 腳位 17 | SSTRB — Serial strobe (conversion status) |
| 腳位 18 | CNVST — Conversion start input |
| 腳位 19 | CS — Chip select (active low) |
| 腳位 20 | SCLK — Serial clock input |
典型應用
MAX1228ACEP+T 適用於 6 應用s: Industrial Process Control & 4-20 mA Loop Digitization, Multi-Channel Data Acquisition Front End, Battery Pack Monitoring & Management, Portable Instrumentation & Handheld Testers, Embedded Control Loop Digitization, Medical Patient Monitoring & Diagnostic Equipment.
Industrial Process Control & 4-20 mA Loop Digitization
The MAX1228ACEP+T fits 4-20 mA loop digitization thanks to its true bipolar ±12 V input range, 12 single-ended channels, and integrated 4.096 V reference, all in one QSOP-20 footprint. With 300 ksps throughput, the device digitizes multiple sensor loops sequentially without pipeline delay, simplifying system timing. Place input protection resistors and an antialiasing RC filter ahead of AIN0-AIN11, and bypass REF with a 1 µF ceramic capacitor within 5 mm of the pin. Unlike external MUX+op-amp+ADC designs, this single-IC integration cuts BOM count by 5+ parts.
推薦
Multi-Channel Data Acquisition Front End
The MAX1228ACEP+T's 12 single-ended inputs at 12-bit/300 ksps are ideal for multi-channel data acquisition boards sampling thermocouples, RTDs, and strain gauges. The integrated 16-entry FIFO buffers burst-conversion sequences, offloading the host MCU in real-time control systems. The internal ±1 °C temperature sensor enables on-board cold-junction compensation alongside the same SPI bus. Compared with discrete ADC + external MUX designs, the MAX1228 reduces PCB area by ~30% and removes firmware overhead for channel sequencing.
推薦
Battery Pack Monitoring & Management
The MAX1228ACEP+T is well suited to battery-pack monitoring because its bipolar ±12 V input range covers individual cell voltages from a multi-cell stack directly, eliminating external resistive dividers for low-channel-count stacks. With 300 ksps throughput and 12-bit resolution, it tracks State-of-Charge parameters across 12 cells simultaneously. Low-power shutdown modes extend battery life in portable packs, and the SPI-compatible interface runs from any embedded microcontroller. The internal temperature sensor additionally monitors pack thermal conditions on a dedicated ADC channel.
推薦
Portable Instrumentation & Handheld Testers
Portable instrumentation benefits from the MAX1228ACEP+T's small QSOP-20 footprint, integrated reference, FIFO buffer, and temperature sensor - eliminating multiple external components and shrinking handheld PCB area. The 300 ksps throughput enables responsive real-time waveforms on handheld oscilloscope probes and field-tester front ends. Hardware shutdown modes extend battery runtime in mobile form factors. The internal ±1 °C temperature sensor also enables self-calibration routines during boot-up.
推薦
Embedded Control Loop Digitization
Embedded control loops - motor control, PLCs, and HVAC systems - benefit from the MAX1228ACEP+T's deterministic SAR conversion latency, which avoids the pipeline delays of higher-speed pipeline ADCs. With 12-bit resolution and 12 channels, it directly digitizes multiple feedback signals (current, voltage, temperature, position) without external multiplexing. The SPI interface is compatible with all major microcontroller families, and the FIFO supports deterministic sampling at fixed loop rates.
推薦
Medical Patient Monitoring & Diagnostic Equipment
The MAX1228ACEP+T suits medical patient monitoring front ends where multi-channel sensor digitization (ECG, SpO2, temperature, respiration) requires low power, small footprint, and reliable SAR conversion. Its 12-bit resolution suffices for vitals monitoring; the internal temperature sensor provides on-board ambient tracking; and the FIFO offloads host processors in compliance-critical devices. Bipolar inputs simplify electrode and transducer interfaces. For diagnostic imaging or higher-precision applications, a 16-bit companion ADC is recommended alongside this part.
推薦
推薦產品摘要
工程參考資料，適用於 MAX1228ACEP+T — 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 | MAX1228ACEP+ | MAX1228BCEP+ | MAX1228BEEP+ | MAX1226CEP+ | MAX1230CEP+ | MAX1202ACAP |
|---|---|---|---|---|---|---|---|
| Brand | Analog Devices (Maxim) | Analog Devices (Maxim) | Analog Devices (Maxim) | Analog Devices (Maxim) | Analog Devices (Maxim) | Analog Devices (Maxim) | Analog Devices (Maxim) |
| Package | 20-QSOP | 20-QSOP (same) | 20-QSOP (same) | 20-QSOP (same) | 20-QSOP (same) | 20-QSOP (same) | 20-QSOP (same) |
| Resolution | 12 bit | 12 bit | 12 bit | 12 bit | 12 bit | 12 bit | 14 bit |
主要差異化特點
- 12 single-ended channels with internal reference and FIFO in a 20-QSOP (對比MAX1226CEP+)
- Higher-resolution upgrade path within same package (對比MAX1202ACAP)
- Drop-in speed upgrade available (對比MAX1228BCEP+)
設計說明
Bypass the analog (AVDD) and digital (DVDD) supply pins individually with 0.1 µF ceramic capacitors placed within 5 mm of each pin, plus a bulk 10 µF tantalum capacitor at the supply entry point. AGND and DGND should be tied at a single star ground near the device; failure to isolate the noisy digital return from the analog ground return introduces conversion noise and degrades the 12-bit linearity.
Route analog input traces (AIN0-AIN11) as far from the SCLK and DOUT traces as possible, and guard them with an AGND pour to minimize digital crosstalk. Place the input protection resistors and antialiasing RC filter network as close to the AIN pins as possible; long input traces pick up switching noise from the digital interface. The QSOP-20 thermal pad (if present) should be soldered to the AGND pour for mechanical and thermal stability.
Do not omit the 1 µF REF bypass capacitor; the internal 4.096 V reference requires this bypass for stability and linearity at full 300 ksps throughput. Also, ensure the CNVST pulse meets the minimum high-pulse width (typically 40 ns); an excessively short CNVST may not initiate conversion. When using the internal temperature sensor, configure the multiplexer to the temperature channel and observe the calibration offset specified in the datasheet for accurate ±1 °C readings.
合規資訊
RoHS and REACH compliance per Maxim/Analog Devices product declaration. Not AEC-Q100 qualified - choose MAX1228AEEP+ variants for extended-temperature applications. Halogen-free status not stated in public datasheets - confirm with manufacturer for specific revisions.
