LTC1857IG - 8-Channel 12-Bit 100ksps ADC | Analog Devices
MPN： LTC1857IG ✓ 啟用中LTC1857IG 概覽
An analog-to-digital converter is an interface IC that converts continuous analog voltages into numerical values for processing by a microcontroller, DSP, or other digital control system. The LTC1857 belongs to the ADC hierarchy, where resolution, conversion rate, input bandwidth, channel count, and interface characteristics determine the measurement precision and throughput available to the end system.
The LTC1857 combines an eight-channel multiplexer, 12-bit conversion resolution, and a sampling rate of 100ksps. Its input multiplexer can be configured for single-ended signals or differential input pairs. Programmable unipolar and bipolar ranges support industrial sensor acquisition, process-control signals, and bipolar measurement systems without requiring a separate external range-selection circuit.
The converter includes an onboard high-performance sample-and-hold circuit and precision reference, which minimize external component requirements. Its stated power dissipation is 40 mW, and two user-selectable shutdown modes help reduce consumption when the acquisition system does not require continuous conversion. The LTC1857 is specified at ±1 LSB integral nonlinearity.
Typical applications include eight-channel industrial data acquisition, thermocouple and transducer interfaces, factory monitoring, process-control equipment, and embedded measurement systems. Its software-programmable input ranges are particularly useful when one ADC must support several sensors operating across different voltage scales.
Design the input network to preserve the selected range and provide suitable settling between multiplexer transitions. Maintain adequate bypass capacitance at the 5 V supply and use the manufacturer pin-description table when assigning analog, digital, reference, and shutdown connections. Verify timing, acquisition sequencing, and overvoltage conditions in the final system.
This page organizes the LTC1857IG specifications, verified drop-in alternatives, input-range guidance, and practical design considerations into a compact engineering reference for selecting, purchasing, and implementing the converter.
直接替換替代品，適用於 LTC1857IG — 相同封裝，腳位對腳位相容。需重新設計 PCB 的不同封裝零件不列入。
LTC1857IG#PBF
✅ 直接替換📋 參考替代品（不在目錄中）
LTC1857CG#PBF
✅ 直接替換📋 參考替代品（不在目錄中）
LTC1858IG#PBF
✅ 直接替換 ⚠️ 規格未經驗證📋 參考替代品（不在目錄中）
LTC1857IG 最大額定值與電氣特性
| Converter Type | Successive-approximation analog-to-digital converter |
| 解析度 | 12 bit |
| Channel Count | 8 channels |
| 取樣率 | 100 kSPS |
| 供應電壓 | 5 V |
| Power Dissipation | 40 mW |
| Integral Nonlinearity | ±1 LSB |
| Unipolar Input Range 1 | 0 V to 5 V |
| Unipolar Input Range 2 | 0 V to 10 V |
| Bipolar Input Range 1 | ±5 V |
| Bipolar Input Range 2 | ±10 V |
| Analog Input Protection | ±25 V |
| Input Configuration | Single-ended or differential |
| Shutdown Modes | 2 user-selectable modes |
| Onboard Sample-and-Hold | Yes |
| Onboard Reference | Yes, precision reference |
| 封裝 | 28-lead SSOP |
| Temperature Grade | Industrial |
| 安裝類型 | Gull-wing surface mount |
LTC1857IG 28-lead ssop 腳位配置指南
LTC1857IG（28-lead ssop 封裝）的腳位配置。 此類比元件具有輸入、輸出與電源腳位。偏移歸零、補償與致能腳位配置請參閱製造商資料表。適用於訊號調理與放大器電路。
無詳細腳位定義資料： LTC1857IG.
請參閱 資料表 以查看完整腳位配置。
典型應用
LTC1857IG 適用於 6 應用s: Industrial Data Acquisition, Process Control Instrumentation, Factory Sensor Interface, Automated Test Equipment, Power Supply Monitoring, Environmental Monitoring.
Industrial Data Acquisition
The LTC1857IG fits an eight-channel industrial acquisition system that must sample sensors at up to 100ksps while using a single 5 V supply. Its programmable ranges of 0 V to 5 V, 0 V to 10 V, ±5 V, and ±10 V let one converter support several signal classes. The eight-input multiplexer simplifies routing, while the onboard sample-and-hold and reference reduce external circuitry. Because channels are converted sequentially, verify that the required scan time meets the sampling requirement.
推薦
Process Control Instrumentation
The LTC1857IG is suitable for monitoring pressure, temperature, level, and controller outputs in process-control equipment. Its eight channels can be configured as single-ended inputs or differential pairs, allowing the acquisition system to handle both grounded sources and noise-sensitive differential sensors. Software-programmable bipolar ranges support ±5 V and ±10 V industrial signals, while the 12-bit resolution and ±1 LSB INL specification provide a defined conversion accuracy target.
推薦
Factory Sensor Interface
The LTC1857IG can interface a group of analog sensors when the system needs more channels than a low-channel ADC provides. Eight inputs, a 100ksps maximum sampling rate, and selectable unipolar or bipolar spans support transducers with different output levels. The converter operates from one 5 V rail and includes an onboard sample-and-hold circuit and precision reference, helping standardize acquisition hardware across multiple factory monitoring nodes.
推薦
Automated Test Equipment
The LTC1857IG can serve as the measurement converter in automated test equipment that scans several analog test points at 100ksps. Its programmable ranges make it possible to cover both low-voltage unipolar sources and bipolar control signals without a fixed analog front end for every channel. The 12-bit result width is appropriate for production screening, calibration, and diagnostics where fast multiplexing and deterministic input configuration are more important than maximum resolution.
推薦
Power Supply Monitoring
The LTC1857IG can monitor several power rails, controller outputs, or analog reference nodes in a multi-rail system. Its 0 V to 10 V programmable range accommodates higher-voltage measurement nodes, while differential operation can improve rejection of common-mode disturbances on balanced sensing lines. Running from a single 5 V supply simplifies auxiliary measurement circuitry, and shutdown modes can reduce consumption during inactive monitoring intervals.
推薦
Environmental Monitoring
The LTC1857IG supports embedded environmental monitoring nodes that acquire readings from multiple resistive, voltage-output, or bipolar sensors. Eight selectable channels reduce the need for multiple converter packages, and the programmable spans can accommodate sensors with different signal amplitudes. Its 100ksps rate provides margin above the sampling needs of many temperature, humidity, light, and air-quality systems while its 12-bit resolution preserves meaningful measurement granularity.
推薦
推薦產品摘要
工程參考資料，適用於 LTC1857IG — 比較、設計指引及合規資訊。
選型指南
與替代品比較
| 參數 | 本產品 | LTC1857IG#PBF | LTC1857CG#PBF | LTC1858IG#PBF |
|---|---|---|---|---|
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices |
| Package | SSOP-28 | SSOP-28 | SSOP-28 | SSOP-28 |
| Resolution | 12 bit | 12 bit | 12 bit | 14 bit |
| Channel Count | 8 channels | 8 channels | 8 channels | 8 channels |
| Sampling Rate | 100 kSPS | 100 kSPS | 100 kSPS | 100 kSPS |
| Supply Voltage | 5 V | 5 V | 5 V | 5 V |
| Integral Nonlinearity | ±1 LSB | ±1 LSB | ±1 LSB | ±1.5 LSB |
| Programmable Input Ranges | 0 V to 5 V, 0 V to 10 V, ±5 V, or ±10 V | 0 V to 5 V, 0 V to 10 V, ±5 V, or ±10 V | 0 V to 5 V, 0 V to 10 V, ±5 V, or ±10 V | 0 V to 5 V, 0 V to 10 V, ±5 V, or ±10 V |
| Power Dissipation | 40 mW | 40 mW | 40 mW | 40 mW |
主要差異化特點
- Provides the exact 12-bit conversion resolution required by the target design (對比LTC1858IG#PBF)
- Maintains the specified LTC1857 accuracy class (對比LTC1858IG#PBF)
- Combines eight channels with a 100ksps conversion rate (對比MCP3424-E/SL)
設計說明
Keep analog input traces short, place the LTC1857IG close to the signal source, and route analog and digital return paths carefully to minimize coupling from switching circuitry. The 28-lead SSOP provides separate analog and digital functions that require deliberate partitioning. Use the manufacturer pin-description table to confirm every connection, especially the supply, ground, shutdown, and multiplexer input assignments.
Do not treat ±25 V input protection as an operating range. The normal programmable measurement spans are 0 V to 5 V, 0 V to 10 V, ±5 V, and ±10 V, and sustained operation outside the selected span can produce incorrect conversion results. Add input limiting or channel-switching protection where fault conditions can exceed the intended measurement range.
Allow adequate acquisition and settling time whenever the multiplexer changes channels. The eight inputs are scanned sequentially rather than sampled simultaneously, so source impedance, sample-and-hold behavior, and the selected differential or single-ended mode affect the time required for a valid result. Validate the complete scan rate against the 100ksps per-conversion rating and the accuracy required by the application.
Decouple the 5 V supply locally and follow the manufacturer bypass recommendations. The converter's stated dissipation is 40 mW, so its own thermal burden is generally modest, but input protection networks, reference loading, and nearby circuitry can add heat and noise. Use shutdown mode when continuous acquisition is unnecessary to reduce system consumption between measurement bursts.
合規資訊
The LTC1857IG is identified as an industrial-temperature ADC. The #PBF ordering form denotes a lead-free finish, while the base LTC1857IG designation does not by itself establish RoHS, REACH, halogen-free, or conflict-minerals status. AEC-Q100 qualification is not stated for this product.
