TC3400VPA - 16-Bit Sigma-Delta ADC, 8-PDIP | Microchip
部品番号: TC3400VPA ✓ 生産中| 数量 | 単価 | 小計 |
|---|---|---|
| 1 | $3.95 | $3.95 |
| 10 | $3.45 | $34.50 |
| 100 | $2.78 | $278.00 |
| 500 | $2.35 | $1,175.00 |
| 1,000 | $2.05 | $2,050.00 |
TC3400VPA 概要
An ADC (analog-to-digital converter) is an integrated circuit that samples continuous analog voltage signals and converts them into discrete digital codes usable by microcontrollers and processors. Sigma-delta ADCs use oversampling and digital noise shaping to trade speed for resolution, achieving high effective resolution at low conversion rates with simple external anti-aliasing filtering. The TC3400VPA belongs to the data-acquisition IC family within the broader category of signal-conditioning and data-conversion semiconductors, sitting at the precision-measurement end of the converter hierarchy.
Key features include +2.7V to +5.5V single-supply operation, 260 uA typical operating supply current, 0.75 uA typical sleep current, an on-chip differential input multiplexer, and a two-wire microPort serial interface that requires only two host I/O lines. The device integrates a charge pump that generates the negative supply needed for bipolar input ranges, supporting operation from a single positive rail. Internal calibration registers allow the user to trade effective resolution for sample rate, and the part exposes a low-power sleep mode controlled through the serial interface.
Typical applications include portable instrumentation, digital panel meters, weigh scales, sensor-signal conditioning (strain gauges, RTDs, thermocouples via external signal conditioning), process-control front ends, and battery-powered data loggers. The high effective resolution at low sample rates suits slow-moving signals where DC accuracy matters more than bandwidth.
When designing with this device, place a 0.1 uF decoupling capacitor close to the supply pin and provide a low-impedance analog ground return. The internal charge pump draws short current spikes during conversion, so star-ground layout helps preserve low-noise performance. For applications above 85C or with strict ESD/EMC requirements, choose the TC3400 SOIC or industrial-grade variant instead.
ドロップイン代替品: TC3400VPA — 同一パッケージでピン互換。PCBの作り直しが必要な異なるパッケージの部品は除外されています。
クイック比較ツール — 並列比較する代替部品を選択:
TC3400EUA
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TC3400VUA
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TC3400XUA
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MCP3421A0T-E/CH
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TC3400VPA 最大定格＆電気的特性
| 分解能 | 16 bits (15 bits plus sign) |
| Converter Type | Sigma-Delta |
| Number of Input Channels | 1 differential |
| Sample Rate (16-bit) | 8 samples per second |
| Sample Rate (10-bit) | 512 samples per second |
| Supply Voltage Range | +2.7 V to +5.5 V |
| Operating Supply Current | 260 uA (typical) |
| Sleep Current | 0.75 uA (typical) |
| Data Interface | Serial (microPort, 2-wire) |
| 動作温度 | 0C to +85C |
| パッケージ | 8-PDIP (0.300 in / 7.62 mm) |
| 実装タイプ | Through-Hole |
| Packaging | Tube |
TC3400VPA ピン構成
| ピン 1 | VREF — External reference voltage input |
| ピン 2 | AIN+ — Differential analog input positive |
| ピン 3 | AIN- — Differential analog input negative |
| ピン 4 | GND — Ground |
| ピン 5 | SCLK — Serial clock input (microPort) |
| ピン 6 | SDATA — Serial data (microPort, bidirectional) |
| ピン 7 | CS — Chip select / enable input |
| ピン 8 | VDD — Positive supply voltage (+2.7 V to +5.5 V) |
主な用途
TC3400VPA の用途: 6 件s: Digital Weigh Scales, Digital Panel Meters, Battery-Powered Data Loggers, Strain Gauge and Load Cell Readout, Process Control Front End, Portable Medical Instrumentation.
Digital Weigh Scales
The TC3400VPA's 16-bit effective resolution at 8 conversions per second and integrated charge pump for bipolar inputs make it well-suited to weigh-scale signal chains. Its sigma-delta architecture shapes quantization noise out of the low-frequency band where load-cell signals reside, providing inherent rejection of 50/60 Hz mains interference without external filtering. Paired with a load cell (typically 350 ohm bridge, 1 mV/V sensitivity) and a low-noise instrumentation amplifier such as the Microchip MCP6N11, the TC3400VPA delivers the dynamic range required for commercial scales (typically 0.01 percent nonlinearity over a 1 kg to 100 kg range). The 0.75 uA sleep current allows battery-powered portable scales to retain the last reading for months on a single coin cell. Compared to a higher-speed SAR ADC, the TC3400VPA trades bandwidth for resolution, which is exactly the trade-off weigh-scale designs need.
おすすめ
Digital Panel Meters
The TC3400VPA is a strong fit for digital panel meters measuring DC voltage, current, temperature, or pressure in industrial front panels. Its single +2.7 V to +5.5 V supply and 260 uA operating current enable direct connection to common 5 V or 3.3 V microcontroller rails without auxiliary regulators, simplifying the meter BOM. The microPort 2-wire serial interface requires only two I/O pins on the host MCU, leaving more pins available for displays, buttons, and communication. With 16-bit resolution at 8 samples per second, the TC3400VPA easily resolves 4-1/2 digit panel-meter accuracy (approximately 20,000 counts) for slowly varying process signals. The internal charge pump handles bipolar inputs so a single positive rail suffices for +/-10 V measurements after external resistive division.
おすすめ
Battery-Powered Data Loggers
The TC3400VPA's 0.75 uA sleep current and 260 uA active current make it well-suited to long-life battery-powered data loggers used in environmental monitoring, cold-chain transport, and remote sensor installations. The device can be placed in sleep mode between samples and woken via its serial interface, drawing essentially zero current in standby. Its 16-bit sigma-delta resolution accurately digitizes slow-changing signals such as battery voltage, temperature (via external RTD or thermistor bridge), and humidity (via external capacitive sensor). With 8 samples per second capability, the TC3400VPA can oversample for averaging and noise reduction, extending battery life by allowing the host microcontroller to remain in sleep longer between burst-sampling events. A typical AA-battery logger can run for months to years depending on sample interval.
おすすめ
Strain Gauge and Load Cell Readout
The TC3400VPA is widely used to digitize strain-gauge bridge outputs in structural-health monitoring, force gauges, and pressure transducers. The 16-bit effective resolution at low sample rates exceeds the typical strain-gauge accuracy requirement of approximately 0.05 percent, while the integrated charge pump allows bipolar excitation of the bridge from a single positive supply rail. Combined with a low-noise instrumentation amplifier (MCP6N11 or equivalent) and a precision reference (MCP1525 or MCP1541), the TC3400VPA implements a complete 4-wire strain-gauge readout channel. Sigma-delta noise shaping provides inherent rejection of mains-frequency interference picked up by long sensor cables, a common issue in industrial strain-gauge installations. The microPort interface allows a small 8-pin MCU to read the ADC with minimal firmware overhead.
おすすめ
Process Control Front End
The TC3400VPA suits industrial process-control front ends measuring 4-20 mA loop signals, RTD temperatures, or thermocouple-derived voltages after external conditioning. Its bipolar-input capability (via internal charge pump) and 16-bit resolution at 8 conversions per second give the dynamic range needed for loop-powered transmitters and remote I/O modules. The compact 8-PDIP package and minimal external component count (one bypass cap and a reference) simplify manufacturing and reduce field-service complexity. The microPort interface allows isolated signal-chain designs using digital isolators on the two serial lines while keeping the ADC side of the isolation barrier simple. Industrial PLC and DCS integrators often choose the TC3400 family for slow-but-accurate analog inputs where sigma-delta noise shaping is preferred over SAR conversion.
おすすめ
Portable Medical Instrumentation
The TC3400VPA's combination of low power (260 uA active, 0.75 uA sleep), small package, and 16-bit resolution suits portable medical devices such as blood-pressure monitors, glucose meters, and pulse oximeters where battery life and measurement precision are equally critical. Its differential input and integrated charge pump support direct connection to bridge-type pressure sensors or photodiode amplifiers used in pulse-oximetry front ends. The sigma-delta noise shaping rejects ambient 50/60 Hz interference common in clinical environments, eliminating the need for expensive shielding or active filtering. Compliance with IEC 61010-1 for measurement equipment is achievable through additional external protection, and the part's long-term availability from Microchip provides the lifecycle support required for medical device production runs.
おすすめ
おすすめ製品の概要
エンジニアリング参考データ: TC3400VPA — 比較、設計ガイダンス、コンプライアンス情報。
選定ガイド
代替品との比較
| パラメータ | この製品 | TC3400EUA | TC3400VUA | TC3400XUA | MCP3421A0T-E/CH |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 8-PDIP (0.300 in) | 8-SOIC - same die | 8-MSOP - same die | 8-MSOP lead-free - same die | SOT-23-6 |
| Resolution | 16 bits | 16 bits | 16 bits | 16 bits | 18 bits |
| Sample Rate (max) | 8 sps @ 16-bit / 512 sps @ 10-bit | 8 sps @ 16-bit / 512 sps @ 10-bit | 8 sps @ 16-bit / 512 sps @ 10-bit | 8 sps @ 16-bit / 512 sps @ 10-bit | 3.75 to 240 sps |
| Supply Voltage | +2.7 V to +5.5 V | +2.7 V to +5.5 V | +2.7 V to +5.5 V | +2.7 V to +5.5 V | +2.7 V to +5.5 V |
| Operating Current | 260 uA | 260 uA | 260 uA | 260 uA | 145 uA |
| Sleep Current | 0.75 uA | 0.75 uA | 0.75 uA | 0.75 uA | 0.1 uA |
| Interface | microPort (2-wire serial) | microPort (2-wire serial) | microPort (2-wire serial) | microPort (2-wire serial) | I2C (standard 2-wire) |
| Price (qty 1) | $3.95 | $2.95 | $2.85 | $2.90 | $1.85 |
主な差別化要因
- True single-supply operation with internal bipolar charge pump （vs MCP3421A0T-E/CH)
- Proprietary microPort interface requires only two MCU pins （vs MCP3421A0T-E/CH)
- Through-hole PDIP package option for prototype and hobby markets （vs TC3400EUA (SOIC))
設計ノート
The TC3400VPA requires a clean +2.7 V to +5.5 V supply; place a 0.1 uF ceramic decoupling capacitor as close as possible to the VDD pin (pin 8) with a low-impedance ground return. The internal charge pump draws short current spikes during conversion, so a star-ground layout with separate analog and digital ground returns is recommended. For battery-powered applications, route the VDD pin through a low-quiescent LDO (e.g., Microchip MCP1700 with 1.6 uA Iq) rather than the battery directly to suppress supply noise. The 0.75 uA sleep current assumes the serial interface is idle; verify by checking the CS pin is held high in sleep to disable the internal oscillator.
Route the analog input traces (AIN+ at pin 2, AIN- at pin 3) as a tightly-coupled differential pair with ground guarding on both sides to reject common-mode noise. Keep digital traces (SCLK at pin 5, SDATA at pin 6, CS at pin 7) physically separated from the analog traces and cross them only at right angles. The TC3400VPA's sigma-delta modulator is sensitive to digital noise coupling onto the analog inputs; ensure the PCB's analog ground plane is contiguous under the device and not interrupted by digital return currents.
Use a 4-layer PCB with a dedicated ground plane (layer 2) and power plane (layer 3) for best noise performance; a 2-layer board is acceptable for hobby or low-noise-budget designs if the ground side is kept mostly unbroken under the device. Place the VREF bypass capacitor (typically 0.1 uF ceramic in parallel with 10 uF tantalum) within 5 mm of pin 1; VREF is the reference node for the sigma-delta modulator and any noise here directly degrades conversion accuracy. Add a small ferrite bead (600 ohm at 100 MHz) in series with VDD if the supply is shared with switching regulators or other noisy digital circuitry.
コンプライアンス情報
TC3400VPA is a through-hole PDIP part, generally not RoHS-compliant; the same silicon is offered in lead-free SOIC (TC3400XUA) for RoHS-compliant designs. AEC-Q100 is not applicable because the part is not specified for automotive use.
