MCP42100-I/P - 100kΩ 8-Bit SPI Digital Potentiometer | Microchip
料号： MCP42100-I/P ✓ 量产中MCP42100-I/P 概述
A digital potentiometer is a programmable resistive element whose effective resistance or divider ratio is controlled by digital commands. Unlike a mechanical potentiometer, it offers repeatable electronic adjustment, software-controlled calibration, and stable operation without moving contacts. The MCP42100 belongs to the digital potentiometer hierarchy, which includes SPI-controlled resistor networks used for gain control, offset adjustment, sensor conditioning, and programmable voltage division.
The MCP42100 provides 256 discrete tap positions, equivalent to 8-bit wiper resolution. Its 100kΩ resistance value is useful when the circuit requires relatively high impedance or modest current capability. The SPI interface allows the wiper code to be updated from a host microcontroller, making the device suitable for systems that need runtime calibration or user-adjustable analog control without mechanical wear.
The manufacturer specifies an SPI interface operating with modes 0,0 and 1,1. An 8-bit wiper setting can therefore be transferred efficiently, while the fixed 100kΩ end-to-end resistance provides a consistent base for circuit calculations. The 2.7V to 5.5V supply range supports common embedded, industrial-control, instrumentation, and communications equipment operating from 3.3V or 5V rails.
Typical uses include sensor-signal conditioning, programmable amplifier gain control, instrument calibration networks, programmable voltage dividers, and embedded user interfaces. The SPI connection also allows multiple digitally controlled functions to share a bus when chip-select handling is implemented correctly. In systems where one control function requires continuous adjustment, software updates can replace a physical trimmer or potentiometer.
Design the external network around the 100kΩ resistance value and confirm that the intended signal current remains within the device's application limits. Place the device near the protected or divided signal path when minimizing trace resistance and noise pickup is important. Treat all SPI writes as wiper updates, and establish a defined power-up state in host firmware so the analog output does not remain at an unintended position.
This page combines the manufacturer's device characteristics with application-specific engineering guidance, interface considerations, and a package-matched comparison. It also distinguishes the verified 14-pin PDIP option from other MCP42100 package configurations so engineers can assess PCB reuse without treating different footprints as drop-in replacements.
直接替换替代料： MCP42100-I/P ——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： MCP42100-I/P （相同外形与封装尺寸） ——差异在于 Control Interface, Device Type.
AD5232BRU100
✅ 直接替换📋 参考替代料（不在目录中）
MCP42100-I/P 最大额定值与电气特性
| Device Type | Single-channel digital potentiometer |
| 分辨率 | 8 bit |
| Number of Taps | 256 taps |
| End-to-End Resistance | 100 kΩ |
| Wiper Adjustment | Linear |
| Control Interface | SPI serial interface |
| Supply Voltage Range | 2.7 V to 5.5 V |
| SPI Clock Modes | Mode 0,0 and mode 1,1 |
| 封装 | 14-pin PDIP |
| 安装类型 | Through-hole |
| Integrated Nonlinearity | ±1 LSB maximum |
| Differential Nonlinearity | ±1 LSB maximum |
| Digital Interface | Industry-standard SPI interface |
| Wiper Storage | Volatile |
MCP42100-I/P 14-pin pdip 引脚配置指南
MCP42100-I/P（14-pin pdip 封装）的引脚配置。 引脚编号、功能和连接图在制造商数据手册中定义。请参阅该手册以了解确切的封装尺寸和焊接指南。
暂无详细引脚数据： MCP42100-I/P.
请参阅 数据手册 以查看完整引脚配置。
典型应用
MCP42100-I/P 适用于 6 应用s: Programmable Sensor Signal Conditioning, Programmable Amplifier Gain Control, Programmable Voltage Divider, Instrumentation and Test Equipment Calibration, Communications Equipment Attenuation, Embedded User-Interface Adjustment.
Programmable Sensor Signal Conditioning
The MCP42100-I/P fits sensor-conditioning circuits that require a digitally adjustable resistance rather than a mechanical trimmer. Its 100kΩ network, linear 256-position wiper, and SPI control allow firmware to trim offset, balance, or threshold behavior around a sensor network. The 2.7V to 5.5V operating range supports both 3.3V and 5V embedded platforms. Because the wiper state is volatile, the host controller should establish the required code during startup, and production designs should use stored calibration constants where repeatable accuracy is needed.
推荐
Programmable Amplifier Gain Control
The MCP42100-I/P can serve as a digitally adjustable gain element in an analog amplifier path. With 100kΩ resistance, 8-bit resolution, and 256 linearly spaced taps, it provides a practical range of attenuation or feedback adjustment for instrumentation and embedded signal-chain designs. SPI updates allow gain settings to change without mechanical controls. The design should account for the resistance of external summing or feedback components and verify the resulting gain error across the operating signal range before production calibration.
推荐
Programmable Voltage Divider
The MCP42100-I/P is well suited to a programmable voltage-divider function where firmware must select an analog ratio from 256 discrete positions. Its linear wiper behavior and 100kΩ end-to-end resistance make the tap code easy to translate into an intended divider setting. The SPI interface supports quick adjustment during calibration or test. Choose suitable resistor and buffer arrangements around the device, and verify divider accuracy, input impedance, and signal loading at the highest and lowest programmed tap positions.
推荐
Instrumentation and Test Equipment Calibration
The MCP42100-I/P supports automatic adjustment and calibration in laboratory or field-test equipment where a fixed resistor network would require manual rework. Software can write a new wiper code through SPI, record the resulting calibration value, and restore it during later tests. With 256 positions and a 100kΩ base resistance, the part fits moderate-range trim networks rather than high-precision metrology chains. Use repeatable switch references, stable excitation, and stored calibration data to keep measurement repeatability within the complete instrument error budget.
推荐
Communications Equipment Attenuation
The MCP42100-I/P can provide digitally controlled attenuation or impedance adjustment in communications equipment operating from a 3.3V or 5V rail. Its 256 taps and linear 100kΩ movement allow firmware to fine-tune a signal level, balance a termination network, or implement an adjustable threshold. The serial interface makes settings easy to integrate with system supervision. Validate insertion loss, return behavior, and noise performance in the complete signal path because the digital potentiometer is one element of the overall channel performance.
推荐
Embedded User-Interface Adjustment
The MCP42100-I/P lets a controller implement a software-adjustable analog setting without a mechanical rotary control. A user interface can update the wiper code through SPI in response to buttons, a display, or a remote command, while the analog circuit responds immediately. The 14-pin PDIP format is useful for through-hole industrial-control assemblies, and the 2.7V to 5.5V supply range supports embedded processors. Define startup behavior and maximum adjustment limits in firmware to protect downstream circuitry from unintended settings.
推荐
推荐产品汇总
工程参考数据： MCP42100-I/P ——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 | AD5232BRU100 |
|---|---|---|
| Device Type | Single-channel digital potentiometer | Dual-channel digital potentiometer |
| Brand | Microchip Technology | Analog Devices |
| Package | 14-pin PDIP | 14-lead PDIP - package-matched |
| End-to-End Resistance | 100 kΩ | 100 kΩ |
| Resolution | 8 bit | 8 bit |
| Number of Taps | 256 taps | 256 taps |
| Control Interface | SPI serial interface | SPI serial interface |
| Channel Count | 1 channel | 2 channels |
关键差异点
- Single-channel implementation preserves the intended one-channel architecture （对比 AD5232BRU100)
- Identical principal resistance and resolution （对比 AD5232BRU100)
- Package-matched 14-pin through-hole implementation （对比 AD5232BRU100)
设计说明
Keep the MCP42100-I/P close to the analog network that uses its wiper output. Short wiper and terminal traces reduce added resistance and susceptibility to capacitive coupling, particularly when the 100kΩ network is part of a precision divider or amplifier feedback path. Route the SPI signals away from sensitive analog nodes, provide a ground return beneath the relevant area if the PCB layout permits it, and follow the package-specific land pattern in the Microchip manufacturer datasheet.
Treat the SPI bus as a digital control network even when it writes a wiper setting used by an analog signal path. Keep clock and data traces short, use a defined chip-select strategy, and account for the supported SPI modes 0,0 and 1,1 in firmware. Establish a deterministic startup code before the controlled analog node becomes active because the wiper setting is volatile. This prevents an intermediate or unintended resistance from affecting sensitive analog behavior during power initialization.
Do not select another MCP42100 suffix solely because its resistance and resolution appear similar. The -I/P ordering code identifies the 14-pin PDIP configuration, while other package options use different footprints and may not fit or route on the same PCB. Also avoid assuming that 256 taps guarantees 8-bit absolute accuracy. The published ±1 LSB nonlinearity limits describe tap-to-tap behavior, while overall system accuracy also depends on external resistors, temperature, loading, and calibration.
Operate the MCP42100-I/P only within its 2.7V to 5.5V supply range and use a common ground between the device and the controlling microcontroller. Confirm that the external network cannot force an endpoint or wiper voltage outside the device's operating limits. If the controlled signal has a larger voltage range, use appropriate protection and isolation components. Validate the complete analog path at both supply extremes because digital control timing and analog behavior remain linked through the common device supply.
合规信息
The manufacturer product page and ordering information used here do not state the requested compliance statuses, so each field remains unknown. Confirm Pb-free, RoHS, REACH, automotive qualification, and halogen-free declarations against the current Microchip product documentation before release.
