MAX1241BEPA - 12-Bit SAR ADC, 73ksps, 2.7-5.25V | Maxim Integrated
料号： MAX1241BEPA ✓ 量产中| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $6.77 | $6.77 |
| 10 | $6.1 | $61.00 |
| 100 | $5.41 | $541.00 |
| 500 | $4.83 | $2,415.00 |
| 1,000 | $4.32 | $4,320.00 |
MAX1241BEPA 概述
A SAR ADC is a successive-approximation-register analog-to-digital converter that uses a comparator, an internal DAC, and a binary-search algorithm to convert an analog input into a digital code, typically in one to several microseconds. As a member of the SAR converter hierarchy -> ADC -> data converter -> signal chain IC -> mixed-signal semiconductor, the MAX1241BEPA is suited to medium-speed, medium-accuracy instrumentation and process-control applications where deterministic latency and simple serial interfacing outweigh the need for higher throughput or true bipolar input ranges.
Key features include an input track-and-hold (T/H) front end that eliminates the need for an external sample-and-hold, single-supply operation up to +5.25V, internal 2.5V reference, and a hardware shutdown pin that drops supply current to under 10uA. The MAX1241 supports an external reference input, allowing the full-scale range to be scaled to suit sensor outputs such as 4-20mA-derived voltages or thermocouple signals.
Architecturally, the MAX1241BEPA uses a BiCMOS SAR core with a charge-redistribution DAC, achieving 12-bit INL of +/-1 LSB and DNL of +/-1 LSB (max). Its serial clock rates up to 2.1MHz at 5V and SPI/QSPI/MICROWIRE-compatible logic enable straightforward connection to virtually any microcontroller or DSP without external glue logic.
Typical applications include portable data loggers, battery-powered instrumentation, process-control analog input modules, temperature sensor digitizers (with external reference trimming), and pen-digitizer / touch panels. The wide 2.7V-5.25V supply range also lets it operate directly from a 3.3V or 5V microcontroller rail.
When designing with this device, place the 0.1uF supply bypass capacitor as close to VDD as possible and ensure the REF bypass (typically 4.7uF) is low-ESR to keep reference noise below 1 LSB. The MAX1241BEPA differs from the MAX1240 in supply range (2.7V-5.25V vs 2.7V-3.6V) and the MAX1241AEPA in accuracy grade and operating temperature window.
This page consolidates distributor pricing (from DigiKey, Mouser, LCSC and Octopart snapshots as of 2026-10-14), parametric drop-in alternatives in the same 8-pin PDIP footprint, and practical layout guidance not always summarised on the manufacturer datasheet.
直接替换替代料： MAX1241BEPA ——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： MAX1241BEPA （相同外形与封装尺寸） ——差异在于 Package.
快速对比工具——选择替代料号进行并排对比：
MAX1241BCPA+
✅ 直接替换📋 参考替代料（不在目录中）
MAX1241ACPA+
✅ 直接替换📋 参考替代料（不在目录中）
MAX1241CCPA+
✅ 直接替换📋 参考替代料（不在目录中）
MAX1240BEPA+
✅ 直接替换✓ 有现货
$5.55 / 个
查看数据手册 →MAX1241CEPA+
✅ 直接替换📋 参考替代料（不在目录中）
MAX1241BEPA 最大额定值与电气特性
| 分辨率 | 12 bits |
| Architecture | SAR (Successive Approximation) |
| Number of Channels | 1 single-ended input |
| Sample Rate | 73 ksps (max) |
| Conversion Time | 7.5 us (typical) |
| Supply Voltage (VDD) | +2.7 V to +5.25 V (single supply) |
| Supply Current (Operating) | 1.3 mA (typical at 73 ksps, VDD=5V) |
| Supply Current (Power-Down) | 5 uW (max 10 uA typical) |
| Internal Reference | 2.5 V |
| External Reference Input | Supported |
| Input Range | 0 V to VREF (unipolar, single-ended) |
| INL (Integral Non-Linearity) | +/-1 LSB (max) |
| DNL (Differential Non-Linearity) | +/-1 LSB (max, no missing codes) |
| Serial Interface | SPI/QSPI/MICROWIRE-compatible (mode 0/MODE 0) |
| Serial Clock Frequency | Up to 2.1 MHz (VDD=5V); 1.0 MHz (VDD=3V) |
| 工作温度范围 | -40 C to +85 C (industrial) |
| 封装 | 8-pin PDIP (through-hole, 8-PDIP) |
| MSL 等级 | 1 (unlimited floor life) |
MAX1241BEPA 引脚配置
| 引脚 1 | VDD — Positive supply voltage (+2.7V to +5.25V) |
| 引脚 2 | AIN — Analog input (single-ended, 0V to VREF) |
| 引脚 3 | REF — Reference I/O (internal 2.5V out, or external reference in) |
| 引脚 4 | AGND — Analog ground - connect to DGND at a single point |
| 引脚 5 | DGND — Digital ground |
| 引脚 6 | SSTRB — Conversion-status output (active low, marks valid data) |
| 引脚 7 | DOUT — Serial data out (MSB-first, SPI/QSPI/MICROWIRE mode 0) |
| 引脚 8 | SCLK — Serial clock input (up to 2.1 MHz at VDD=5V, 1 MHz at VDD=3V) |
典型应用
MAX1241BEPA 适用于 6 应用s: Portable Battery-Powered Data Logger, Process Control Analog Input Module, Temperature Sensor Digitiser, Industrial Weigh Scale / Strain-Gauge Front End, Pen-Digitizer / Touch Panel Digitiser, Test & Measurement Handheld Instrument.
Portable Battery-Powered Data Logger
The MAX1241BEPA fits portable battery-powered data loggers because its +2.7V to +5.25V supply range allows direct operation from two fresh AA cells, a 3.3V LDO, or a USB-derived 5V rail without level shifting. Its 7.5 microsecond conversion time at 73 ksps lets a low-power microcontroller sample sensors at 1 Hz to 10 kHz with deterministic latency, and the shutdown pin drops current to under 10 microampere between conversions - achieving the roughly 1000x active-to-standby ratio that drives multi-year coin-cell runtimes. Place a 4.7uF low-ESR bypass on REF (internal 2.5V reference) so reference drift does not eat into the +/1 LSB INL budget at slow sample rates.
推荐
Process Control Analog Input Module
In process-control analog input modules, the MAX1241BEPA digitises 4-20 mA-derived shunt voltages and thermocouple-conditioned thermocouple-conditioned millivolt signals with the SPI/QSPI/MICROWIRE-compatible serial interface directly wired to a PLC or industrial MCU. Driving the REF pin from an external +5.000V reference scales the 0-VREF unipolar input range to full industrial sensor spans, while the track-and-hold front end removes the need for an external sample/hold stage. Its -40 C to +85 C industrial temperature range tolerates cabinet locations, and the +/1 LSB INL/DNL means no missing codes across the SAR core.
推荐
Temperature Sensor Digitiser
The MAX1241BEPA is a natural fit for temperature-sensor digitisation with platinum RTDs, thermistors or solid-state sensors when paired with a low-offset front-end amplifier. The internal 2.5V reference plus an external ratiometric reference mode (driving the same excitation voltage to the RTD bridge and to REF) cancels lead-resistance and reference errors first-order, while the 12-bit resolution yields roughly 0.6 C per LSB over a 0-150 C span - more than enough for most HVAC and appliance loops. The 8-pin PDIP footprint keeps the analog front end compact enough to colocate the ADC with the sensor on a remote board.
推荐
Industrial Weigh Scale / Strain-Gauge Front End
Weigh-scale and strain-gauge front ends benefit from the MAX1241BEPA's differential-style measurement technique: a single-ended analog input digitises the bridge-output voltage with respect to REF, while ratiometric sensing (using the same REF-derived excitation for the bridge) cancels bridge self-heating drift. The SAR architecture's excellent noise rejection and lack of pipeline latency make the part safe for dc-stabilised measurements where readings must not strobe or wander, and the +/1 LSB INL delivers repeatable counts to within 0.024 percent over a 0-2.5V full scale.
推荐
Pen-Digitizer / Touch Panel Digitiser
The MAX1241BEPA's 73 ksps sample rate and 7.5 us conversion time make it usable in digitiser and touch-panel applications where the host samples X/Y or pressure line voltages at 1 kHz or higher. Its small 8-pin PDIP footprint keeps the analog frontend compact, while the SPI/QSPI/MICROWIRE-compatible serial data output drops cleanly into the host's SPI peripheral with no glue logic. Single-supply +2.7V to +5.25V operation also means the same ADC works whether the panel controller runs from a 3.3V LDO or a 5V regulated rail.
推荐
Test & Measurement Handheld Instrument
Handheld test and measurement instruments exploit the MAX1241BEPA's combination of low quiescent current, integrated 2.5V reference and 12-bit accuracy to digitise voltage, current and sensor-derived signals in battery-powered multimeters. The shutdown pin's <10uA standby current preserves battery life when the meter is in hold, while the 73 ksps throughput supports 1000+ readings per second on demand for transient capture. The MAX1241BEPA's 8-pin PDIP pinout also allows a single PCB layout to be reused across 3.3V and 5V instrument SKUs with only a BOM swap.
推荐
推荐产品汇总
工程参考数据： MAX1241BEPA ——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 | MAX1241BCPA+ | MAX1241ACPA+ | MAX1241CCPA+ | MAX1240BEPA+ | MAX1241CEPA+ |
|---|---|---|---|---|---|---|
| Package | 8-PDIP (through-hole) | 8-PDIP - same | 8-PDIP - same | 8-PDIP - same | 8-PDIP - same | 8-PDIP - same |
| Brand | Maxim Integrated | Maxim Integrated | Maxim Integrated | Maxim Integrated | Maxim Integrated | Maxim Integrated |
| Resolution | 12 bits | 12 bits | 12 bits | 12 bits | 12 bits | 12 bits |
| Sample Rate | 73 ksps | 73 ksps | 73 ksps | 73 ksps | 73 ksps | 73 ksps |
| Supply Voltage | +2.7V to +5.25V | +2.7V to +5.25V | +2.7V to +5.25V | +2.7V to +5.25V | +2.7V to +3.6V | +2.7V to +5.25V |
| Internal Reference | 2.5V | 2.5V | 2.5V | 2.5V | 2.5V | 2.5V |
| Operating Temperature | -40 C to +85 C (B-grade industrial) | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C |
| Shutdown Current (SHDN bar) | <10 uA (5 uW max) | <10 uA | <10 uA | <10 uA | <10 uA | <10 uA |
关键差异点
- Wider supply-voltage headroom (5.25V vs 3.6V) （对比 MAX1240BEPA+)
- B-grade +/1 LSB INL industrial accuracy （对比 MAX1241BCPA+ (B-grade vs A/C siblings))
- Internal 2.5V reference with external override （对比 MAX1084BCSA+ (12-bit-only ADC, no internal 2.5V ref))
设计说明
Place a 0.1uF ceramic bypass as close to VDD (pin 1) as the 8-PDIP pin pitch allows - the SAR converter draws brief current spikes during the internal DAC settling period, and any series inductance between VDD and the chip can couple switching noise into the analog input. Also bypass VREF (pin 3) with a 4.7uF low-ESR capacitor (tantalum or polymer aluminum) per Maxim's reference design to keep reference noise below 1 LSB; using a ceramic-only bypass here will allow noise-induced gain error.
Route the analog input (AIN, pin 2) on a top-layer guard trace that is bounded by ground flood on both sides. Maxim's MAX1241 datasheet recommends keeping the analog trace short and away from SCLK (pin 8) and DOUT (pin 7) traces to avoid digital feedback into the analog front end. Reference the ADC analog ground (AGND, pin 4) and digital ground (DGND, pin 5) together at a single star ground near the reference bypass capacitor, not at multiple points.
When using an external reference instead of the internal 2.5V bandgap, buffer the reference with a low-noise op-amp such as the MAX6126 or MAX6325 to avoid reference current transients during the 7.5 us conversion. Drive REF from an op-amp with <5 uV/ms slew rate of its own and route the reference trace on the bottom layer with a top-side ground flood for shielding - using a high-impedance source here will couple sample-and-hold clock glitches into the SAR comparator and add 1-2 LSB of noise.
Do not apply inputs above VDD or below AGND to AIN (pin 2) - exceeding the rail can latch up the ESD diodes and permanently damage the part. Also note that the MAX1241 requires 13 SCLK edges to complete a conversion (a starter bit + 12 data bits), not 12; leaving the chip with no SCLK after the 13th edge stalls the conversion. Finally, ensure SCLK is idle-low before CS is asserted - mode 0 (CPOL=0, CPHA=0) is mandatory.
合规信息
RoHS/REACH/lead-free status was not explicitly stated in the provided web data for the MAX1241BEPA (no '+' suffix visible in the queried MPN). The Maxim 'B' suffix indicates industrial temperature grade; RoHS compliance for the non-'+' part cannot be confirmed from the supplied snippet and is reported as unknown. AEC-Q100 does not apply (industrial/non-automotive). Check the ADI/Maxim product page for definitive compliance data.
