ADS7841E/2K5G4 - 12-Bit 4-Ch 200kHz SAR ADC | Texas Instruments
部品番号: ADS7841E/2K5G4 ✗ 生産終了| 数量 | 単価 | 小計 |
|---|---|---|
| 1 | $9.06 | $9.06 |
| 10 | $8.15 | $81.50 |
| 100 | $7.25 | $725.00 |
| 500 | $6.4 | $3,200.00 |
| 1,000 | $5.7 | $5,700.00 |
ADS7841E/2K5G4 概要
A successive-approximation register ADC (SAR ADC) is a type of analog-to-digital converter that uses a binary-search algorithm against an internal precision DAC to resolve an analog input to N bits in N clock cycles. SAR ADCs sit in the broader hierarchy of ADC architectures, which also includes delta-sigma, pipeline, flash, and dual-slope converters. Compared to pipeline ADCs they offer lower latency and no pipeline delay, and compared to delta-sigma parts they deliver much higher sampling rates at moderate resolution - making the 12-bit 200 kHz SAR a sweet spot for multiplexed data acquisition, instrumentation, and pen/digitizer front-ends.
Key features of the ADS7841E include 4 single-ended or 2 differential input channels, a single +2.7V to +5.25V supply rail, 72 dB SINAD, a synchronous SPI/SSI-compatible serial interface with 8-bit or 12-bit programmable resolution, and typical power dissipation of just 2 mW at 200 kHz throughput on a +5V supply. The reference voltage VREF can be varied between 100 mV and VCC, allowing direct scaling to sensor output spans. An auto-power-down mode reduces consumption between conversions, and the SSOP-16 footprint is pin-compatible with the legacy ADS7841ES and ADS7843 family.
The device is specified over the -40°C to +85°C industrial temperature range. Communication is via a 4-wire serial interface (CS, DCLK, DIN, DOUT) plus BUSY, supporting daisy-chaining of multiple ADS7841s on the same bus. A SHDN pin and PD0/PD1 bits implement low-power standby modes between conversions. Internal architecture uses a charge-redistribution DAC with a switched-capacitor comparator, yielding excellent DC linearity and very low aperture uncertainty suitable for touch-screen digitizer applications.
Typical applications include 4-wire resistive touch-screen controllers, pen-digitizer digitizing tablets, industrial process-control data acquisition modules, portable battery-powered instrumentation, and general-purpose multiplexed analog input modules for embedded systems. The wide VREF range also makes it suitable for thermocouple and bridge-sensor front-ends. The part is also marketed as an alternate source for the legacy ADS7841ES, easing second-source qualification for existing designs.
When designing with the ADS7841E/2K5G4, ensure the VREF decoupling capacitor is placed within 5 mm of the REF pin to avoid conversion errors, and route the BUSY signal away from the analog inputs to prevent digital crosstalk into the sampled value. Note that the ADS7841E/2K5G4 is now marked obsolete by Texas Instruments with no direct replacement; designers should evaluate the active parametric equivalent ADS7841E/2K5 or migrate to the ADS7843/ADS7844 family for new designs.
This page synthesizes distributor pricing, drop-in equivalents, and practical design notes that go beyond what is in the manufacturer datasheet, giving engineers a single reference for legacy, current-production, and cross-brand options in the same SSOP-16 footprint.
ドロップイン代替品: ADS7841E/2K5G4 — 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。
このシリーズのバリエーション
同一シリーズでドロップイン互換のモデル: ADS7841E/2K5G4 （同一形状・フットプリント） — 相違点: Package, Mounting Type, Resolution, DNL (Max), Operating Temperature.
クイック比較ツール — 並列比較する代替部品を選択:
ADS7841E/2K5
✅ ドロップイン📋 参考代替品（カタログ未掲載）
ADS7841EB/2K5G4
✅ ドロップイン📋 参考代替品（カタログ未掲載）
ADS7841ESG4
✅ ドロップイン📋 参考代替品（カタログ未掲載）
ADS7841ES/2K5G4
✅ ドロップイン📋 参考代替品（カタログ未掲載）
ADS7841PG4
✅ ドロップイン✓ 在庫あり
$4.32 / 個
データシートを見る →ADS7841PBG4
✅ ドロップイン✓ 在庫あり
$4.12 / 個
データシートを見る →ADS7841E/2K5G4 最大定格＆電気的特性
| 分解能 | 12 bits (also 8-bit mode) |
| Number of Input Channels | 4 single-ended / 2 differential |
| Architecture | SAR (Successive Approximation Register) |
| サンプリングレート | 200 kHz (max) |
| Conversion Time | 3.75 us |
| INL (Max) | ±1 LSB |
| DNL (Max) | ±1 LSB |
| Missing Codes | None (12-bit guaranteed) |
| SINAD | 72 dB |
| 電源電圧 | 2.7 V to 5.25 V (single supply) |
| Reference Voltage (VREF) | 100 mV to VCC |
| Power Dissipation | 2 mW typical at 200 kHz, 5 V |
| Serial Interface | SPI/SSI-compatible synchronous (CS, DCLK, DIN, DOUT, BUSY) |
| 動作温度 | -40 C to +85 C |
| パッケージ | SSOP-16 (QSOP-16) |
| 実装タイプ | Surface Mount |
| RoHS ステータス | Compliant (G4 suffix = lead-free) |
| Auto Power-Down | Yes (PD0/PD1 / SHDN pin) |
ADS7841E/2K5G4 ピン構成
| ピン 1 | VREF — Voltage reference input (100 mV to VCC) |
| ピン 2 | NC — No internal connection (per datasheet) |
| ピン 3 | A0 / IN+ — Analog input channel 0 / positive differential input |
| ピン 4 | A1 / IN- — Analog input channel 1 / negative differential input |
| ピン 5 | A2 / IN+ — Analog input channel 2 / positive differential input |
| ピン 6 | A3 / IN- — Analog input channel 3 / negative differential input |
| ピン 7 | AUX — Auxiliary analog input |
| ピン 8 | VDD — Positive supply (2.7 V to 5.25 V) |
| ピン 9 | GND — Ground |
| ピン 10 | DCLK — External serial data clock |
| ピン 11 | DIN — Serial data input |
| ピン 12 | DOUT — Serial data output |
| ピン 13 | BUSY — ADC busy output (low during conversion) |
| ピン 14 | CS — Chip select (active low) |
| ピン 15 | SHDN — Shutdown input (active low) |
| ピン 16 | PD — Power-down mode select |
主な用途
ADS7841E/2K5G4 の用途: 6 件s: 4-Wire Resistive Touch-Screen Controller, Industrial Data Acquisition Module, Pen Digitizer Tablet Front-End, Portable Battery-Powered Instrumentation, Medical Patient Monitoring Front-End, General-Purpose Multiplexed Analog Input Module.
4-Wire Resistive Touch-Screen Controller
The ADS7841E/2K5G4's 4 single-ended channels and 12-bit SAR resolution are a natural fit for 4-wire resistive touch-screen digitizing. The device drives the touch-panel X/Y planes through A0-A3 and converts the analog voltage tap with 72 dB SINAD and ±1 LSB linearity. Its 200 kHz throughput supports >100 touch points/sec when the host samples repeatedly, and the synchronous SPI interface streams coordinates directly to the MCU. Lower latency vs delta-sigma ADCs makes touch feel responsive without overshoot.
おすすめ
Industrial Data Acquisition Module
Industrial PLC and process-control front-ends benefit from the ADS7841E/2K5G4's 4-channel input multiplexer, allowing four 0-5V sensor signals to share one ADC. The 200 kHz throughput multiplexes 4 channels at 50 kHz each, adequate for thermocouple, RTD-bridge, and 4-20 mA shunt monitoring. ±1 LSB INL/DNL and no-missing-codes 12-bit performance meet typical ±0.1% measurement budgets. The 2.7-5.25 V single supply simplifies interface to 3.3 V or 5 V microcontrollers.
おすすめ
Pen Digitizer Tablet Front-End
Active and passive pen digitizer tablets rely on the ADS7841E/2K5G4's fast conversion and low latency for tracking the pen's X/Y position across the active area. The 4-channel input handles X-plate, Y-plate, and pen-pressure signals through a single chip, reducing BOM cost. Synchronous serial output streams coordinates at the host SPI clock rate, and the BUSY pin lets the host know when the next conversion is complete, minimizing host polling overhead in low-power handheld designs.
おすすめ
Portable Battery-Powered Instrumentation
Handheld multimeters and portable instrumentation benefit from the ADS7841E/2K5G4's 2 mW typical power dissipation at full speed, dropping to microamps in auto-power-down between conversions. The 2.7 V minimum supply operation supports direct 3 V lithium battery power, and the wide VREF range (100 mV to VCC) accommodates low-voltage sensor bridges without external gain stages. The SSOP-16 footprint keeps the bill of materials small for compact handheld enclosures.
おすすめ
Medical Patient Monitoring Front-End
Medical telemetry and bedside monitors digitize multiple biopotential channels (ECG, SpO2, temperature) through a multiplexer. The ADS7841E/2K5G4's 4-channel input and 12-bit resolution suit low-frequency bioelectric signals, and its 72 dB SINAD preserves signal integrity. The 3.75 us conversion time is well below ECG bandwidth requirements. Its serial interface isolates the analog front-end from the digital MCU, reducing EMI into sensitive measurement channels.
おすすめ
General-Purpose Multiplexed Analog Input Module
Embedded systems that need to monitor 4 analog sensors (temperature, light, position, voltage) benefit from the ADS7841E/2K5G4's pin-friendly 4-channel multiplexer and standard SSOP-16 footprint. The 200 kHz throughput supports up to 50 kHz per channel multiplexed, and the SPI interface requires no address pins - freeing MCU I/O for other functions. No missing codes at 12-bit guarantees monotonic readings for closed-loop control applications like HVAC and motor drives.
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: ADS7841E/2K5G4 — 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 | ADS7841E/2K5 | ADS7841EB/2K5G4 | ADS7841ESG4 | ADS7841ES/2K5G4 | ADS7841PG4 |
|---|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Package | SSOP-16 (QSOP-16) | SSOP-16 (QSOP-16) - same | SSOP-16 (QSOP-16) - same | SSOP-16 (QSOP-16) - same | SSOP-16 (QSOP-16) - same | SSOP-16 (QSOP-16) - same |
| Resolution | 12-bit (8-bit mode) | 12-bit (8-bit mode) | 12-bit (8-bit mode) | 12-bit (8-bit mode) | 12-bit (8-bit mode) | 12-bit (8-bit mode) |
| Sampling Rate | 200 kHz | 200 kHz | 200 kHz | 200 kHz | 200 kHz | 200 kHz |
| Channels | 4 SE / 2 DIFF | 4 SE / 2 DIFF | 4 SE / 2 DIFF | 4 SE / 2 DIFF | 4 SE / 2 DIFF | 4 SE / 2 DIFF |
| Supply Voltage | 2.7 V to 5.25 V | 2.7 V to 5.25 V | 2.7 V to 5.25 V | 2.7 V to 5.25 V | 2.7 V to 5.25 V | 2.7 V to 5.25 V |
| Lifecycle Status | Obsolete | Active (recommended replacement) | Obsolete | Obsolete | Obsolete | Obsolete |
| RoHS / Lead-Free (G4) | Yes (G4 suffix) | Yes | Yes (G4) | Yes (G4) | Yes (G4) | Yes (G4) |
主な差別化要因
- Recommended drop-in substitute is the active-production same-die part （vs ADS7841E/2K5)
- No-missing-codes 12-bit SAR performance （vs ADS7843E/2K5)
- Single 2.7-5.25 V supply with 2 mW typical power （vs ADS7825UE4)
設計ノート
Place a 10 uF tantalum and 0.1 uF ceramic decoupling pair within 5 mm of VDD (pin 8) and a single 0.1 uF ceramic within 5 mm of VREF (pin 1). The VREF bypass is critical for conversion accuracy - inadequate VREF decoupling directly raises INL and DNL because the reference is sampled at every conversion. Use a low-impedance ground pour under the SSOP-16 thermal pad.
Route the analog inputs (A0-A3, AUX) and reference (VREF) on one side of the SSOP-16 footprint, kept away from DCLK, DIN, DOUT, BUSY, and CS. The BUSY pin toggles at every conversion and couples digital noise into analog traces if routed in parallel. Place the MCU on the opposite PCB side and use a ground guard trace around the analog input traces to minimize digital crosstalk.
Keep the SPI clock (DCLK) below the datasheet maximum of 1.6 MHz and use a series 33 ohm resistor at the MCU DCLK output to dampen reflections on longer board traces. When daisy-chaining multiple ADS7841s, add a 100 ohm pull-up on DOUT near the host MCU. A BUSY-nCS skew of at least 50 ns ensures the host does not read stale conversion data.
Do not leave SHDN (pin 15) floating - tie to VDD through a 100 kohm resistor or drive it actively, since the chip powers up in shutdown by default. The PD bit at CS rising edge resets the converter; a CS pulse shorter than 50 ns may not register a new conversion start. Always enter power-down between conversions in battery applications to achieve the 2 mW typical / <1 uA standby performance claimed in the datasheet.
コンプライアンス情報
G4 suffix denotes lead-free / RoHS-compliant assembly per TI's standard suffix convention. Part is now obsolete; REACH status not separately verified on distributor pages.
