ADS7841ES/2K5 - 12-Bit 4-Ch 200kHz SAR ADC | Texas Instruments
料号： ADS7841ES/2K5 ✓ 量产中| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $6.45 | $6.45 |
| 10 | $5.8 | $58.00 |
| 100 | $5.15 | $515.00 |
| 500 | $4.6 | $2,300.00 |
| 1,000 | $4.1 | $4,100.00 |
| 2,500 | $3.7 | $9,250.00 |
ADS7841ES/2K5 概述
A SAR ADC is a successive-approximation-register analog-to-digital converter that uses a binary-search algorithm combined with an internal DAC to digitize an input sample in N clock cycles, where N is the resolution in bits. SAR ADCs sit within the broader analog-to-digital converter family (SAR > ADC > data converter > signal chain IC > semiconductor) and are favored over sigma-delta and pipeline architectures when low latency, single-shot conversions, and moderate-to-high sampling rates (tens of kHz to a few MHz) are required in multiplexed-channel applications.
Key specifications include 12-bit resolution (programmable to 8 or 12 bits via the MODE pin/bit), 4 single-ended or 2 differential input channels, 3.75 µs typical conversion time, 0.0488 % linearity error, single +2.7 V to +5 V supply operation, and a synchronous serial (SPI-compatible) interface. Typical power dissipation is 2 mW at 200 kHz throughput with a +5 V supply, and the reference voltage VREF can vary between 100 mV and VCC for input scaling flexibility.
The ADS7841 implements a four-wire SPI/SSI-compatible synchronous serial interface with a BUSY output, making it straightforward to interface with microcontrollers, DSPs, and modern SoCs. The 16-bit SSOP (DBQ) package is a thin-shrink small-outline outline surface-mount form factor from the SSOP family, providing a compact 5.3 mm body width suitable for space-constrained data-acquisition boards.
Typical applications include pen-touch digitizers, battery-monitoring systems, isolated data acquisition, industrial process control, and portable instrumentation. The /2K5 suffix indicates tape-and-reel packaging with 2500-unit reels, oriented toward production-volume assembly.
When designing with this part, place the 0.1 µF VCC bypass capacitor as close as possible to the supply pin and route the BUSY and DOUT lines away from noisy switching nodes to preserve the 72 dB SINAD figure at full speed. The MODE pin defaults to 12-bit mode when held LOW, allowing software override when held HIGH.
This page consolidates distributor pricing, pin-compatible drop-in alternatives, and practical PCB design notes not found in the standalone manufacturer datasheet, with the goal of accelerating the engineer selection and review process.
直接替换替代料： ADS7841ES/2K5 ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
快速对比工具——选择替代料号进行并排对比：
ADS7841E/2K5
✅ 直接替换📋 参考替代料（不在目录中）
ADS7841ESG4
✅ 直接替换📋 参考替代料（不在目录中）
ADS7841ESG4/2K5
✅ 直接替换📋 参考替代料（不在目录中）
ADS7841ES
✅ 直接替换📋 参考替代料（不在目录中）
MAX1247
✅ 直接替换📋 参考替代料（不在目录中）
ADS7841ES/2K5 最大额定值与电气特性
| 分辨率 | 12 bits (programmable to 8 bits) |
| Number of Input Channels | 4 single-ended or 2 differential |
| Conversion Rate (Throughput) | 200 kHz max |
| Conversion Time | 3.75 µs typical |
| Architecture | SAR (Successive Approximation Register) |
| INL (Max) | ±1 LSB |
| DNL (Max) | ±1 LSB |
| Missing Codes | None guaranteed |
| SINAD | 72 dB |
| Linearity Error | 0.0488 % |
| Supply Voltage (VCC) | +2.7 V to +5 V (single supply) |
| Reference Voltage (VREF) | 100 mV to VCC |
| Typical Power Dissipation | 2 mW at 200 kHz, +5 V |
| 接口 | Synchronous Serial (SPI/SSI compatible) |
| 封装 | 16-pin SSOP (DBQ) |
| 安装类型 | Surface Mount |
| 工作温度 | -40 °C to +125 °C |
| Packaging | Tape & Reel (2500 pcs/reel) |
ADS7841ES/2K5 引脚配置
| 引脚 1 | CH0 — Analog input channel 0 |
| 引脚 2 | CH1 — Analog input channel 1 |
| 引脚 3 | CH2 — Analog input channel 2 |
| 引脚 4 | CH3 — Analog input channel 3 |
| 引脚 5 | GND — Ground reference |
| 引脚 6 | VREF — Voltage reference input (100 mV to VCC) |
| 引脚 7 | VCC — Positive supply (2.7 V to 5 V) |
| 引脚 8 | DOUT — Serial data output |
| 引脚 9 | BUSY — Conversion-in-progress indicator |
| 引脚 10 | DIN — Serial data input |
| 引脚 11 | CS — Chip select (active low) |
| 引脚 12 | DCLK — Serial data clock |
| 引脚 13 | MODE — Resolution mode select (LOW=12-bit fixed; HIGH=controlled by MODE bit) |
| 引脚 14 | AUX — Auxiliary analog input |
| 引脚 15 | SHDN — Shutdown control (active low) |
| 引脚 16 | NC — Not connected (per datasheet) |
典型应用
ADS7841ES/2K5 适用于 6 应用s: Pen-Touch Digitizer Digitization, Multichannel Battery Monitoring System, Isolated Industrial Data Acquisition, Portable Medical Instrumentation, Closed-Loop Motor Control Feedback, General-Purpose Data Acquisition Module.
Pen-Touch Digitizer Digitization
The ADS7841ES/2K5's 12-bit SAR architecture and 200 kHz throughput make it well suited for resistive touch-screen pen and stylus digitizers, where 4-wire interface measurements of X-plate, Y-plate, and auxiliary channels must be sampled sequentially without the digital filter delay of a sigma-delta ADC. With ±1 LSB INL and 72 dB SINAD, it provides sub-1% positional accuracy in 4-wire and 5-wire touch panels used in PDAs, signature pads, and industrial HMI terminals. The synchronous serial interface connects directly to a microcontroller SPI port with minimal glue logic, and the MODE pin allows the host to dynamically switch between 12-bit precision (for pen tip contact) and 8-bit fast scan (for finger tracking) at the same 200 kHz throughput.
推荐
Multichannel Battery Monitoring System
In a 4-cell lithium-ion or NiMH battery monitor, the ADS7841ES/2K5's 4 single-ended channels allow direct ratiometric measurement of each cell voltage through external resistor dividers, sharing one VREF with the system rail. The 12-bit resolution yields ~1.2 mV LSB at a 4.2 V full scale, adequate for state-of-charge estimation in portable medical and power-tool applications. Typical power dissipation of 2 mW at 200 kHz adds negligible drain to the battery, and the 2.7–5 V single supply lets it ride directly on a single Li-ion cell. Differential mode (2 channels) supports simultaneous current-sense and voltage-sense digitization for coulomb counting.
推荐
Isolated Industrial Data Acquisition
Industrial 4–20 mA loop or 0–10 V process signal acquisition requires low-latency single-shot sampling, which the ADS7841ES/2K5 provides at 200 kHz with no missing codes. The 4 single-ended channels accept four transducer signals (pressure, flow, level, temperature) sharing one VREF, and the 16-pin SSOP footprint fits into compact DIN-rail modules. The synchronous serial output is straightforward to route through a digital isolator (e.g., ISO7640) back to a host microcontroller. ±1 LSB INL delivers better than 0.025% linearity error, sufficient for 12-bit process control loops.
推荐
Portable Medical Instrumentation
Portable patient-monitoring devices (pulse oximeters, handheld ECG, glucose meters) require a small, low-power ADC that digitizes multiple sensor channels at low duty cycle to extend battery life. The ADS7841ES/2K5's 2 mW typical dissipation at 200 kHz (and significantly less at lower clock rates) suits battery-powered designs. The 4-channel input supports photodiode, thermistor, and electrochemical sensor multiplexing in a single chip, and the SSOP-16 footprint fits handheld enclosures. The 72 dB SINAD preserves signal fidelity for diagnostic-grade measurements.
推荐
Closed-Loop Motor Control Feedback
Field-oriented control (FOC) of brushless DC motors requires deterministic, low-latency current and voltage sampling synchronized to the PWM carrier; the SAR-based ADS7841ES/2K5 delivers single-shot conversions in 3.75 µs without sigma-delta's filter group delay. Two differential input pairs handle phase-A and phase-B current-sense signals from shunt resistors, with the auxiliary channel monitoring DC-bus voltage. The SPI-compatible synchronous serial interface lets a motor-control DSP or MCU read all samples within a single PWM cycle. With ±1 LSB INL, current-loop regulation accuracy is preserved at high switching frequencies.
推荐
General-Purpose Data Acquisition Module
Universal 4-channel data-acquisition boards (USB-DAQ, PCI-DAQ) frequently standardize on the ADS7841ES/2K5 for medium-speed, multi-channel measurements where simultaneous sampling is not required. Its 200 kHz throughput aggregated across 4 channels yields 50 kHz per channel—sufficient for vibration, acoustic, and general instrumentation. The synchronous serial bus simplifies FPGA or microcontroller interface designs, and the SSOP-16 package is hand-solderable for prototype builds. ±1 LSB INL/DNL guarantees 12-bit monotonic conversion across the input range, while programmable 8/12-bit modes allow throughput/precision trade-offs.
推荐
推荐产品汇总
工程参考数据： ADS7841ES/2K5 ——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 | ADS7841E/2K5 | ADS7841ESG4 | ADS7841ESG4/2K5 | ADS7841ES | MAX1247 |
|---|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Maxim Integrated |
| Package | SSOP-16 (DBQ) | SSOP-16 (DBQ) - same | SSOP-16 (DBQ) - same | SSOP-16 (DBQ) - same | SSOP-16 (DBQ) - same | SSOP-16 - same |
| Resolution | 12-bit (8/12-bit programmable) | 12-bit (8/12-bit programmable) | 12-bit (8/12-bit programmable) | 12-bit (8/12-bit programmable) | 12-bit (8/12-bit programmable) | 12-bit |
| Number of Channels | 4 SE / 2 DI | 4 SE / 2 DI | 4 SE / 2 DI | 4 SE / 2 DI | 4 SE / 2 DI | 4 SE / 2 DI |
| Throughput (Max) | 200 kHz | 200 kHz | 200 kHz | 200 kHz | 200 kHz | ~150 kHz (-25%) |
| INL (Max) | ±1 LSB | ±1 LSB | ±1 LSB | ±1 LSB | ±1 LSB | ±1 LSB |
| Supply Voltage | +2.7 V to +5 V | +2.7 V to +5 V | +2.7 V to +5 V | +2.7 V to +5 V | +2.7 V to +5 V | +2.7 V to +5 V |
关键差异点
- Programmable 8/12-bit resolution via MODE pin （对比 MAX1247)
- Synchronous serial with explicit BUSY output （对比 ADS7841E/2K5)
- Single-supply 2.7–5 V operation with 2 mW typical power （对比 MAX1247)
设计说明
Place a 0.1 µF ceramic bypass capacitor as close as possible to the VCC pin (pin 7) and a 10 µF tantalum or ceramic bulk capacitor at the supply entry point. The VREF pin (pin 6) requires its own 0.1 µF ceramic decoupling capacitor to minimize reference noise coupling into the conversion result; bypassing VREF directly is critical to maintaining the 72 dB SINAD at 200 kHz throughput.
Route the synchronous serial interface lines (DCLK, DOUT, DIN, CS, BUSY) as short as possible and away from switching converter nodes or PWM signals. Place a ground pour under and around the SSOP-16 footprint, and connect the exposed pad to a low-impedance ground stitch. Keep analog input traces (CH0–CH3) symmetrically routed and free of digital cross-talk, using a ground guard trace around high-impedance analog input nodes.
When operating at the maximum 200 kHz throughput, ensure the microcontroller SPI peripheral provides DCLK with 50% duty cycle and rise/fall times < 25 ns to avoid aperture-time jitter in the ADC. The BUSY pin transitions HIGH at the start of conversion and goes LOW when data is ready; sample BUSY with the MCU and latch DOUT only after the falling edge to prevent reading stale conversion results.
Do not let VREF exceed VCC or fall below 100 mV; the absolute input range tracks VREF, and values outside the datasheet window will saturate the input or degrade linearity. The MODE pin defaults to 12-bit mode when LOW; if you pull it HIGH, the MODE bit in the serial word controls resolution—verify your firmware reflects this. The SHDN pin must be tied HIGH through a pull-up or driven by the MCU; leaving it floating can cause indeterminate startup states.
合规信息
RoHS compliance of the bare ES/2K5 part is not explicitly confirmed in the verified data; the G4-suffixed variants (ADS7841ESG4, ADS7841ESG4/2K5) carry the G4 Green/RoHS-compliant designation per TI suffix convention. AEC-Q100 automotive qualification status not confirmed; do not select this part for automotive safety-critical applications without consulting TI product folder.
