MAX145BEPA - 12-Bit 108ksps 2-Ch Serial ADC | Maxim Integrated
料号： MAX145BEPA ✓ 量产中| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $9.88 | $9.88 |
| 10 | $8.95 | $89.50 |
| 100 | $7.42 | $742.00 |
| 500 | $6.18 | $3,090.00 |
| 1,000 | $5.29 | $5,290.00 |
MAX145BEPA 概述
A SAR (Successive Approximation Register) ADC is a type of analog-to-digital converter that uses a binary search algorithm through an internal DAC to digitize an analog input one bit at a time per clock cycle. SAR ADCs are prized for low latency (deterministic acquisition time), high accuracy at moderate sample rates, and the absence of pipeline delay, making them well-suited to multiplexed multi-channel data-acquisition systems, instrumentation, and process control.
Key features include two single-ended analog input channels (CH0, CH1) selected via software, an analog supply range of +2.7V to +5.25V, an external reference input (REF), and a low supply current that drops to microamp levels in power-down mode. The MAX145BEPA industrial-grade (-40C to +85C) PDIP package supports through-hole assembly and is fully RoHS compliant in the + variant (MAX145BEPA+).
Architecturally, the MAX145BEPA integrates an input sample-and-hold, an internal 12-bit DAC, a comparator, a successive-approximation register, and SPI-compatible digital I/O on a single CMOS die. The automatic power-down function between conversions reduces average supply current to a fraction of the active value, which is critical for battery-powered or energy-harvesting applications.
Typical applications include portable data loggers, industrial process-control front-ends, battery-powered instrumentation, sensor signal conditioning read-out, and handheld metering equipment where 12-bit resolution at up to 108 kilosamples per second is sufficient. When laying out a PCB, keep analog and digital grounds joined at a single point near the ADC GND pin to preserve the 12-bit accuracy across the full sample rate.
直接替换替代料： MAX145BEPA ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
本系列中的变体
可与以下型号直接替换的同系列型号： MAX145BEPA （相同外形与封装尺寸） ——差异在于 Conversion Time, Input Type, Number of Channels, Operating Temperature Range, RoHS Status.
快速对比工具——选择替代料号进行并排对比：
MAX145AEPA
✅ 直接替换✓ 有现货
$5.2 / 个
查看数据手册 →MAX145BEPA+
✅ 直接替换📋 参考替代料（不在目录中）
MAX144BEPA
✅ 直接替换📋 参考替代料（不在目录中）
MAX145BEPA 最大额定值与电气特性
| 分辨率 | 12 bits |
| Number of Channels | 2 (single-ended) |
| Sample Rate | 108 ksps |
| Conversion Time | 7.4 us (successive approximation) |
| Wake-Up Time from Power-Down | 2.5 us |
| Analog Supply Voltage | +2.7 V to +5.25 V |
| Digital Logic Supply | Same as analog supply (single supply) |
| Input Type | Single-ended, CH0 / CH1 |
| Reference Input | External (REF pin) |
| Serial Interface | 3-wire SPI / QSPI / MICROWIRE-compatible |
| Built-in Clock | Yes (internal) |
| Automatic Power-Down | Yes (between conversions) |
| 封装 | 8-pin PDIP (through-hole) |
| 工作温度范围 | -40 C to +85 C (industrial) |
| 安装类型 | Through-Hole |
| RoHS 状态 | Compliant (MAX145BEPA+ variant) |
MAX145BEPA 引脚配置
| 引脚 1 | VDD — Power supply (+2.7V to +5.25V) |
| 引脚 2 | CH0 — Analog input channel 0 |
| 引脚 3 | CH1 — Analog input channel 1 (MAX145 only) |
| 引脚 4 | GND — Ground |
| 引脚 5 | REF — External reference voltage input |
| 引脚 6 | DOUT — Serial data output (SPI) |
| 引脚 7 | CS — Chip select (active low) |
| 引脚 8 | DIN/SCLK — Serial data in / serial clock (shared SPI input) |
典型应用
MAX145BEPA 适用于 6 应用s: Battery-Powered Data Logger, Industrial Process-Control Front-End, Handheld Metering & Test Equipment, Sensor Signal Conditioning Read-Out, Portable Medical Monitoring Devices, Automotive Sensor Read-Out (Non-Safety).
Battery-Powered Data Logger
The MAX145BEPA's 12-bit resolution and 108 ksps sample rate allow accurate digitization of slow analog sensor channels such as temperature, pressure and battery voltage in portable data-logging equipment. According to the MAX144/MAX145 datasheet, automatic power-down reduces active current to a few microamps between conversions, enabling months of operation from a single Li-ion or AA battery pack. With 2 multiplexed channels (CH0/CH1) and an external reference, the MAX145BEPA delivers sufficient dynamic range for sensor signal conditioning while keeping the BOM small.
推荐
Industrial Process-Control Front-End
In PLC analog input modules and process-control instrumentation, the MAX145BEPA digitizes 4-20 mA current-loop or 0-10V transducer signals with 12-bit accuracy at up to 108 ksps aggregate throughput. Its +2.7V to +5.25V single-supply operation tolerates 24V industrial rails after external signal conditioning, and its -40C to +85C industrial temperature grade covers factory-floor environments. The 3-wire SPI interface connects directly to host microcontrollers and PLC communication ASICs without external glue logic.
推荐
Handheld Metering & Test Equipment
The MAX145BEPA's small 8-pin PDIP footprint and low average supply current make it ideal for handheld multimeters, insulation testers and portable calibration instruments. According to the MAX144/MAX145 datasheet, the 2.5 microsecond wake-up from power-down enables continuous on-demand conversions triggered by the host microcontroller, while preserving battery life between measurement cycles. The 7.4 microsecond acquisition-to-conversion latency is fast enough to capture transient signals during automated test sequences.
推荐
Sensor Signal Conditioning Read-Out
For strain-gauge bridges, thermocouple amplifiers and other low-bandwidth sensor front-ends, the MAX145BEPA provides 12-bit resolution with low integral nonlinearity suitable for capturing sensor output voltages in the millivolt-to-5V range. Its external reference input allows scaling the ADC full-scale range to the sensor output swing, maximizing effective resolution. The 3-wire SPI/QSPI/MICROWIRE-compatible interface simplifies integration with common low-power MCUs and DSPs in embedded sensor nodes.
推荐
Portable Medical Monitoring Devices
The MAX145BEPA's combination of 12-bit resolution, 108 ksps capability, low power consumption and -40C to +85C temperature range suits battery-powered medical monitoring peripherals such as pulse-oximeter front-ends, blood-pressure monitor signal read-out, and bedside patient monitors requiring 1-2 analog channels. According to the datasheet, automatic power-down and 2.5 microsecond wake-up minimize average current draw, while the SPI interface enables direct connection to low-power MCUs typically used in medical device designs.
推荐
Automotive Sensor Read-Out (Non-Safety)
While the MAX145BEPA is not AEC-Q100 qualified, its -40C to +85C industrial temperature range and 5V supply tolerance suit non-safety automotive applications such as cabin climate sensor read-out, body-comfort modules and infotainment analog audio level sensing. The 8-pin PDIP package is preferred for prototyping and through-hole production runs in aftermarket automotive electronics. For safety-critical powertrain or ADAS applications requiring AEC-Q100, choose a qualified alternative.
推荐
推荐产品汇总
工程参考数据： MAX145BEPA ——对比、设计指导和合规信息。
选型指南
与替代料对比
| 参数 | 本产品 | MAX145AEPA | MAX145BEPA+ | MAX144BEPA |
|---|---|---|---|---|
| Package | PDIP-8 | PDIP-8 - same | PDIP-8 - same | PDIP-8 - same |
| Brand | Maxim Integrated | Maxim Integrated - same | Maxim Integrated - same | Maxim Integrated - same |
| Resolution | 12 bits | 12 bits | 12 bits | 12 bits |
| Number of Channels | 2 (CH0, CH1) | 2 (CH0, CH1) | 2 (CH0, CH1) | 1 (CH0 only) |
| Sample Rate | 108 ksps | 108 ksps | 108 ksps | 108 ksps |
| Supply Voltage | +2.7V to +5.25V | +2.7V to +5.25V | +2.7V to +5.25V | +2.7V to +5.25V |
| INL/DNL Grade | Standard (B-grade) | A-grade (tighter linearity) | Standard (B-grade), RoHS | Standard (B-grade) |
| RoHS Compliance | Non-compliant (no + suffix) | Non-compliant (no + suffix) | RoHS-compliant (+ suffix) | Non-compliant (no + suffix) |
| Operating Temperature | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C |
关键差异点
- Same-die A-grade with tighter linearity, drop-in compatible （对比 MAX145AEPA)
- RoHS-compliant variant of the same die （对比 MAX145BEPA+)
- Compatible 1-channel variant when CH1 is not used （对比 MAX144BEPA)
设计说明
Route analog (CH0, CH1, REF) and digital (DOUT, DIN/SCLK, CS) traces separately, and join analog and digital grounds at a single point - typically at the ADC GND pin or at the decoupling-capacitor ground. According to the MAX144/MAX145 datasheet reference layout, this star-ground topology preserves 12-bit accuracy at full 108 ksps by preventing digital switching currents from corrupting the analog input and reference voltages.
Place a 0.1 microfarate ceramic decoupling capacitor as close as possible to the VDD pin and a 10 microfarate bulk bypass capacitor at the board supply entry. According to the MAX144/MAX145 datasheet, the internal reference/sample-and-hold settling is sensitive to high-frequency VDD ripple - good bypassing ensures specified INL/DNL is achieved. For systems operating above 50 ksps continuous, add an additional 1 microfarate capacitor in parallel with the 0.1 microfarate.
Do not leave any unused analog input (e.g. CH1 on MAX145) floating - tie unused inputs to midscale or ground to prevent charge-injection crosstalk into the active channel. The REF pin must be driven by a low-impedance reference (or a 10 microfarate + 0.1 microfarate RC network) - never leave REF floating or the conversions will be invalid. The CS pin must be held low during the entire conversion to avoid losing synchronization.
合规信息
Non-compliant for RoHS as the legacy MAX145BEPA lacks the + suffix. The MAX145BEPA+ variant is RoHS compliant and lead-free. Not AEC-Q100 qualified - not suitable for automotive safety-critical applications. Choose qualified parts (e.g. MAX11120ATI+T) for AEC-Q100 designs.
