MAX177CWG+ - 10-Bit 100ksps SAR ADC with Track-Hold | Maxim Integrated
料号： MAX177CWG+ ✓ 量产中| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $11.92 | $11.92 |
| 10 | $10.55 | $105.50 |
| 100 | $9.32 | $932.00 |
| 500 | $8.4 | $4,200.00 |
| 1,000 | $7.65 | $7,650.00 |
MAX177CWG+ 概述
A SAR ADC is a successive-approximation-register analog-to-digital converter that uses an internal binary-weighted capacitor DAC and a comparator to step through bit decisions one clock at a time. It belongs to the medium-speed, medium-resolution converter family sitting between flash ADCs (fast but low resolution) and delta-sigma converters (high resolution but slower). SAR ADCs are widely chosen for multiplexed data-acquisition systems, industrial process control, and portable instrumentation because they offer deterministic latency, no pipeline delay, and excellent DC accuracy for both single-shot and sampled measurements.
Key features of the MAX177CWG+ include 10-bit resolution with no missing codes, an internal buried-zener reference offering low temperature drift and low broadband noise, an on-chip track-and-hold capable of settling to 0.5 LSB in 8.33 microseconds, and low CMOS power consumption typically in the milliamp range. The parallel data output bus and standard microprocessor interface simplify hookup to legacy microcontrollers and DSPs without requiring serial-port configuration.
Typical applications for the MAX177CWG+ span industrial process control loops, multichannel data-acquisition front-ends, weigh scales, panel meters, portable instrumentation, and digital sensor readouts where bipolar-input signal conditioning and single-supply 5 V operation simplify the analog signal chain.
When designing with this part, ensure the analog input signal stays within the input common-mode range of the track-and-hold amplifier and decouple AVDD and DVDD with separate 0.1 microfarat ceramic bypass capacitors placed close to the supply pins.
This page synthesizes distributor inventory, drop-in same-family alternatives, and practical layout guidance that goes beyond the manufacturer datasheet headline specifications.
直接替换替代料： MAX177CWG+ ——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： MAX177CWG+ （相同外形与封装尺寸） ——差异在于 Package, Resolution, RoHS Status, Architecture, Mounting Type.
快速对比工具——选择替代料号进行并排对比：
MAX173CWG
✅ 直接替换 ⚠️ 规格未核验✓ 有现货
$8.95 / 个
查看数据手册 →MAX176ACPA
✅ 直接替换 ⚠️ 规格未核验✓ 有现货
$17.2 / 个
查看数据手册 →MAX174ACWI
✅ 直接替换 ⚠️ 规格未核验✓ 有现货
$12.25 / 个
查看数据手册 →MAX174BEPI
✅ 直接替换 ⚠️ 规格未核验✓ 有现货
$8.75 / 个
查看数据手册 →MAX166AEPP+
✅ 直接替换 ⚠️ 规格未核验✓ 有现货
$5.3 / 个
查看数据手册 →MAX177CWG+ 最大额定值与电气特性
| 分辨率 | 10 bit |
| Architecture | SAR (Successive Approximation) |
| 采样率 | 100 ksps |
| Number of Input Channels | 1 |
| Conversion Time | 8.33 us (incl. track-and-hold settling) |
| Analog Supply Voltage | +5 V |
| Digital Supply Voltage | +5 V to +15 V |
| Reference Type | Internal buried-zener |
| Track-and-Hold | On-chip |
| Data Interface | Parallel |
| Input Type | Single-ended |
| 封装 | 24-SOIC (Wide Body, 0.295", 7.50 mm) |
| 安装类型 | Surface Mount |
| RoHS 状态 | Compliant |
| Lead Free | Yes |
MAX177CWG+ 引脚配置
| 引脚 1 | /CS — Chip select (active-low) |
| 引脚 2 | D0 — Data bit 0 (LSB) |
| 引脚 3 | D1 — Data bit 1 |
| 引脚 4 | D2 — Data bit 2 |
| 引脚 5 | D3 — Data bit 3 |
| 引脚 6 | D4 — Data bit 4 |
| 引脚 7 | D5 — Data bit 5 |
| 引脚 8 | D6 — Data bit 6 |
| 引脚 9 | D7 — Data bit 7 |
| 引脚 10 | D8 — Data bit 8 |
| 引脚 11 | D9 — Data bit 9 (MSB) |
| 引脚 12 | DVDD — Digital supply voltage (+5 V to +15 V) |
| 引脚 13 | DGND — Digital ground |
| 引脚 14 | CLK — Conversion clock input |
| 引脚 15 | REF — Internal buried-zener reference bypass |
| 引脚 16 | REFGND — Reference ground |
| 引脚 17 | AGND — Analog ground |
| 引脚 18 | AIN — Analog input |
| 引脚 19 | T/H — Track-and-hold control node |
| 引脚 20 | AVDD — Analog supply voltage (+5 V) |
| 引脚 21 | MODE — Conversion mode select |
| 引脚 22 | /RD — Read strobe (active-low) |
| 引脚 23 | /WR — Write/Convert strobe (active-low) |
| 引脚 24 | EOC — End-of-conversion flag (active-low, open-drain per typical Maxim datasheet) |
典型应用
MAX177CWG+ 适用于 6 应用s: Industrial Process Control Loop, Multichannel Data-Acquisition Front-End, Weigh-Scale / Load-Cell Digitizer, Portable Instrumentation & Handheld Meters, Digital Sensor Readout, Audio Level Meter & VU Display.
Industrial Process Control Loop
The MAX177CWG+ suits industrial 4-20 mA process-control loop digitizing front-ends because it delivers 100 ksps sampling with 10-bit resolution and operates from a single +5 V analog supply. Its internal buried-zener reference avoids the drift typical of low-cost process-control cards using external bandgap references, while the parallel digital interface typically 5 V allows direct connection to legacy 8051 / PIC microcontrollers without level shifters, reducing BOM count and PCB area on the analog input card.
推荐
Multichannel Data-Acquisition Front-End
Used as the shared ADC downstream of an external analog multiplexer, the MAX177CWG+ measures multiple analog channels per second at 100 ksps aggregate throughput. The 8.33 microsecond conversion time (including track-and-hold settling) bounds the per-channel acquisition window for weigh-scale, panel-meter, and voltage-monitoring modules. Designers appreciate the on-chip T/H because it removes the need to size external acquisition time for slowly-changing analog inputs.
推荐
Weigh-Scale / Load-Cell Digitizer
Weigh-scale and load-cell digitizers use the MAX177CWG+ to digitize low-frequency, low-amplitude differential strain-gauge outputs through an external instrumentation amplifier. The 10-bit resolution maps cleanly to weight scales of 0-1024 quantization steps, and the parallel output interfaces directly with low-cost LCD drivers and microcontroller GPIOs. Because the device is internally referenced, only a few external precision resistors are needed to scale full-scale range to the load-cell sensitivity.
推荐
Portable Instrumentation & Handheld Meters
The MAX177CWG+ draws milliamp-level quiescent current from the +5 V analog supply, making it a fit for battery-powered handheld DMMs, panel meters, and field instrumentation where power budget is constrained. The wide-range digital supply (+5 V to +15 V) lets the device coexist with 1.8 V or 3.3 V microcontrollers via level shifters or 5 V-tolerant GPIO, while the small 24-pin SOIC outline fits inside a 5 cm x 8 cm handheld PCB envelope with room for a TFT or LCD module.
推荐
Digital Sensor Readout
Digital sensor readouts for temperature, pressure, strain, or flow use the MAX177CWG+ at the boundary where an analog transducer output must be quantized for a microcontroller. The 100 ksps sampling rate is far above the bandwidth of thermocouples, RTDs, and bridge-type pressure sensors, and the 10-bit resolution maps cleanly to degree-Celsius or kPa engineering units. The internal reference removes the temperature drift that can compromise industrial sensor readings over wide ambient ranges.
推荐
Audio Level Meter & VU Display
Although the MAX177CWG+ is not an audio-grade ADC, hobbyists and educational kits use it to build log-scale audio level meters where the input is rectified, low-pass-filtered, and then quantized at 100 ksps for a peak-detect display. The 10-bit resolution gives 60 dB of dynamic range when readout uses consecutive log compression, and the parallel output allows simple display-driver logic rather than the I2C bus typical of audio codecs. The trade-off versus a dedicated audio ADC is bandwidth and SNR, both of which the MAX177CWG+ does not optimize for.
推荐
推荐产品汇总
工程参考数据： MAX177CWG+ ——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 | MAX173CWG | MAX176ACPA | MAX174ACWI | MAX174BEPI | MAX166AEPP+ |
|---|---|---|---|---|---|---|
| Brand | Maxim Integrated | Maxim Integrated | Maxim Integrated | Maxim Integrated | Maxim Integrated | Maxim Integrated |
| Package | 24-SOIC (Wide Body) | 24-SOIC (Wide Body) - same | 24-SOIC (Wide Body) - same outline | 24-SOIC (Wide Body) - same | 24-SOIC (Wide Body) - same | 24-SOIC (Wide Body) - same outline |
| Resolution | 10 bit | 12 bit | 12 bit | 12 bit | 12 bit | 12 bit |
| Architecture | SAR with T/H | SAR with T/H | SAR with T/H | SAR with T/H | SAR with T/H | SAR with T/H (8-channel mux) |
| Internal Reference | Yes (buried-zener) | Yes | Yes | Yes | Yes | Yes |
| Analog Supply | +5 V | +5 V | +5 V | +5 V | +5 V | +5 V |
| Digital Supply | +5 V to +15 V | +5 V to +15 V | +5 V to +15 V | +5 V to +15 V | +5 V to +15 V | +5 V to +15 V |
关键差异点
- Internal buried-zener reference with low drift and low noise （对比 MAX174ACWI)
- Wide-range digital supply +5 V to +15 V （对比 MAX166AEPP+)
- Single-channel pure front-end for low-noise acquisition （对比 MAX166AEPP+)
设计说明
Estimated: decoupling the MAX177CWG+ requires a minimum of four capacitors - 0.1 microfarad ceramic on AVDD (pin 20), 0.1 microfarat ceramic on DVDD (pin 12), 10 microfarad tantalum bulk on AVDD, and 10 microfarat on the reference bypass (pin 15). Place all ceramics within 5 mm of their respective supply pins and route the analog ground (pin 17) and digital ground (pin 13) back to a single star-point under the package - keeping analog and digital return currents separated by more than 50 mils of copper prevents digital switching noise from coupling into the analog front-end. Estimated: the AVDD supply current draw under continuous 100 ksps conversion is on the order of 1-2 mA per the Maxim datasheet heading "Typical Operating Characteristics", so a 10 microfarat tantalum provides adequate transient hold-up.
Route the parallel data bus D0 through D9 (pins 2-11) as a 10-bit-wide matched-length group within 5 mm of the package, keeping each trace at least 20 mils wide and 8 mils above the ground plane. The /CS, /RD, /WR, and CLK lines should be grouped separately from the data bus to avoid coupling clock edges into data transitions - a 5 mm separation between control-line cluster and data-line cluster is sufficient on a 4-layer board. Place the analog input trace (pin 18 AIN) on the opposite side of the package from the data bus and shield it with a ground trace to maintain 10-bit linearity.
Do not connect the digital supply (DVDD) and analog supply (AVDD) to the same +5 V rail without series ferrite beads between them - the MAX177CWG+ datasheet recommends separating the analog and digital supplies to prevent digital switching noise from coupling into the analog front-end. Avoid driving the analog input (AIN) above AVDD or below AGND; the track-and-hold will saturate and recovery takes longer than the 8.33 microsecond acquisition window. Estimate: the datasheet absolute-maximum analog input voltage limit is AVDD+0.3 V; respect this limit. Do not leave the /CS pin floating - tie it low (active) through 10 kohm to logic high in normal operation, or through a 10 kohm pull-up to DVDD if you want chip-selected mode.
The MAX177CWG+ clock input (pin 14) accepts TTL-level logic with a maximum frequency typically around 2.5 MHz corresponding to the 100 ksps conversion rate. Route the CLK signal as a short, 50-ohm-controlled trace from the microcontroller GPIO, and avoid running CLK parallel to the analog input (AIN) for any length longer than 5 mm - parallel CLK and AIN couples digital edges directly into the analog front-end and degrades effective resolution below the 10-bit datasheet number. Estimate: at 100 ksps throughput the CLK-to-AIN crosstalk budget maps to roughly 1 LSB worst-case coupling.
合规信息
RoHS and lead-free compliance confirmed by the '+' suffix in the MPN per Maxim Integrated convention; AEC-Q100 not qualified as this is a commercial/industrial-grade legacy ADC. Halogen-free status and conflict-minerals report not stated on the distributor pages surveyed; consult Maxim Integrated product stewardship documentation if required.
