MCP4242-502E/UN - 5kΩ Dual 7-Bit SPI Digital Potentiometer | Microchip
N.º de pieza: MCP4242-502E/UN ✓ Activo| Cant. | Precio unitario | Total |
|---|---|---|
| 1 | $1.78 | $1,78 |
| 10 | $1.55 | $15,50 |
| 100 | $1.22 | $122,00 |
| 500 | $1.02 | $510,00 |
| 1.000 | $0.88 | $880,00 |
MCP4242-502E/UN Descripción general
A digital potentiometer (digiPOT) is a solid-state, electronically-controlled variable resistor that emulates the behavior of a mechanical potentiometer or rheostat through an array of CMOS switches and a resistor ladder, with the active tap set by a digital control word. In the system hierarchy it sits between analog signal-conditioning components (resistors, mechanical pots) and digital logic, functioning as a programmable resistive element for trimming, scaling, and calibration tasks. Compared with mechanical pots, digiPOTs offer higher reliability (no moving parts, no oxidation), finer resolution, remote adjustability, and the ability to store calibrated settings in non-volatile memory.
Key features of the MCP4242-502E/UN include a 5 kΩ end-to-end resistance with ±20% tolerance, 7-bit resolution (128 resistors / 129 wiper positions) per channel, a 2.7 V to 5.5 V single-supply operating range, low-power CMOS operation, and WiperLock™ technology that prevents unwanted wiper changes during power transitions. The dual potentiometer configuration allows simultaneous control of two independent signal paths, while the SPI-compatible interface (Mode 0,0 and 1,1) supports high-speed serial communication with most microcontrollers.
The device architecture combines a precision thin-film resistor ladder, CMOS analog switches, a 7-bit wiper counter, non-volatile EEPROM storage, and an internal charge-pump-driven EEPROM write controller. Each wiper position is recallable at power-up through EEPROM restoration, eliminating the need for software initialization sequences. Typical wiper resistance is approximately 75 Ω, and the device operates with a maximum quiescent current well under 1 mA.
Typical applications include programmable gain amplifiers, LCD contrast and backlight brightness control, sensor calibration and trimming, audio attenuator volume control, voltage divider adjustment, and set-point control in closed-loop systems. The 5 kΩ value is well suited to low-impedance signal paths and bias adjustment circuits where low wiper resistance is critical.
When designing with this part, place 0.1 µF decoupling capacitors close to VDD and observe the EEPROM write timing specifications (typically 5 ms tWC) when reprogramming wiper positions. The MSOP-10 footprint is compatible with hand-soldering and standard reflow profiles.
This page consolidates distributor pricing, verified drop-in alternatives, and practical design notes not found in a single source on the manufacturer datasheet, providing an information-gain perspective for component selection.
Alternativas directas para MCP4242-502E/UN — mismo encapsulado, compatible pin a pin. Se excluyen las piezas de otro encapsulado que requieren retrabajo de la PCB.
Herramienta de comparación rápida — seleccione piezas alternativas para compararlas lado a lado:
MCP4242-103E/UN
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
MCP4242-503E/UN
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
MCP4242-104E/UN
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
MCP4242T-502E/UN
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
MCP4252-502E/UN
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
MCP4242-502E/MF
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
MCP4242-502E/UN Especificaciones
| End-to-End Resistance | 5 kΩ |
| Resistance Tolerance | ±20% |
| Number of Pots | 2 (Dual) |
| Wiper Taps | 129 (7-bit resolution) |
| Number of Resistors in Ladder | 128 |
| Control Interface | SPI (Mode 0,0 and 1,1) |
| Supply Voltage Range | 2.7 V to 5.5 V |
| Rango de temperatura de funcionamiento | -40°C to +125°C (Industrial, "E") |
| Wiper Resistance (typical) | 75 Ω |
| Non-Volatile Memory | Yes (EEPROM, WiperLock™) |
| Configuration | Potentiometer or Rheostat |
| Encapsulado | 10-pin MSOP (UN) |
| Tipo de montaje | Surface Mount |
| Nivel MSL | 1 |
| Estado RoHS | Compliant |
Configuración de pines de MCP4242-502E/UN
| Pin 1 | CS — Chip Select (active low) for SPI interface |
| Pin 2 | SCK — Serial Clock input for SPI |
| Pin 3 | SDI — Serial Data Input (MOSI) |
| Pin 4 | SDO — Serial Data Output (MISO) |
| Pin 5 | VSS — Ground reference |
| Pin 6 | P1A — Potentiometer 1, terminal A |
| Pin 7 | P1W — Potentiometer 1, wiper terminal |
| Pin 8 | P1B — Potentiometer 1, terminal B |
| Pin 9 | P0B — Potentiometer 0, terminal B |
| Pin 10 | P0W — Potentiometer 0, wiper terminal (P0A on some datasheet revisions) |
Aplicaciones típicas
MCP4242-502E/UN es adecuado para 7 aplicacións: Programmable Gain Amplifier Trimming, LCD Contrast and Backlight Brightness Control, Sensor Calibration and Offset Trim, Audio Attenuator / Volume Control, Voltage Divider Adjustment in Power Management, Programmable Threshold / Set-Point Control, IoT and Smart-Sensor Calibration Network.
Programmable Gain Amplifier Trimming
The MCP4242-502E/UN's 5 kΩ end-to-end resistance and 7-bit (129-tap) resolution make it well-suited as a programmable feedback resistor in op-amp gain stages. Its 75 Ω typical wiper resistance is low relative to the 5 kΩ total, minimizing gain error in transimpedance and non-inverting topologies. Designers can replace a fixed gain-setting resistor with the digiPOT and adjust gain in-circuit via SPI from a microcontroller, enabling automatic calibration or user-selectable gain ranges. The dual channel allows independent adjustment of two amplifier stages (e.g., input gain + output gain) on a single chip.
Recomendado
LCD Contrast and Backlight Brightness Control
In character or graphic LCD modules, the MCP4242-502E/UN can replace a mechanical contrast trim pot with a digitally adjustable voltage on the LCD's VEE bias pin. Its 2.7 V to 5.5 V supply range covers both 3.3 V and 5 V LCD systems, and the 129 tap positions provide smooth, repeatable contrast adjustment via SPI commands. The second channel can independently drive a backlight MOSFET gate or LED current-set reference, consolidating two trim functions onto one IC. On-board EEPROM retains user-preferred contrast and brightness across power cycles without firmware reconfiguration.
Recomendado
Sensor Calibration and Offset Trim
Precision analog sensors (strain gauges, thermocouples, pressure transducers) often require per-unit calibration to remove offset and gain errors. The MCP4242-502E/UN can inject a programmable trim voltage into the sensor signal chain or set the reference for a delta-sigma ADC, allowing digital calibration at production test time without manual trimpot adjustment. The 5 kΩ resistance is appropriate for low-impedance bridge sensors, and the 7-bit resolution yields fine 39 Ω tap size (5 kΩ/128), adequate for most calibration trim ranges. Dual channels enable simultaneous offset and gain trim.
Recomendado
Audio Attenuator / Volume Control
In low-cost audio paths, the MCP4242-502E/UN can function as a digital volume control in series with the audio signal. While its 5 kΩ end-to-end resistance is more suited to line-level than headphone drive, the dual channel provides stereo volume control from a single SPI bus, eliminating the need for dual mechanical pots. The 129-step logarithmic-feel adjustment (when wiper settings are mapped logarithmically in software) gives smooth volume changes. WiperLock™ ensures the last volume setting survives power-off, so end-user volume preference is preserved across reboots.
Recomendado
Voltage Divider Adjustment in Power Management
Many adjustable LDO regulators and DC-DC converters use external resistor dividers to set output voltage. The MCP4242-502E/UN can replace one of these divider resistors with a digitally programmable element, enabling dynamic voltage scaling (DVS) or remote output trim. Its 2.7 V to 5.5 V supply range overlaps with typical low-voltage rail signals, and the 75 Ω wiper resistance is small compared to the 5 kΩ total, preserving divider accuracy. The non-volatile memory holds the calibration value even when the system is powered down.
Recomendado
Programmable Threshold / Set-Point Control
In comparator-based threshold detectors (battery low-warning, line-voltage monitors, window comparators), the MCP4242-502E/UN can set the comparator reference voltage digitally rather than with a fixed resistor. This allows end-of-line or field-adjustable trip thresholds without reworking the PCB. The 5 kΩ resistance is appropriate for low-voltage reference nodes, and dual channels enable independent high/low thresholds in window comparator circuits. SPI access permits remote or automated threshold adjustment via a host controller.
Recomendado
IoT and Smart-Sensor Calibration Network
In IoT edge nodes and smart sensors, the MCP4242-502E/UN provides a compact, low-power (sub-1 mA quiescent) calibration element for trimming sensor bridges, setting reference voltages for onboard ADCs, or controlling gain stages without bulky mechanical trimpots. The SPI interface is compatible with virtually any microcontroller or wireless SoC, and the MSOP-10 footprint suits space-constrained PCBAs. Dual channels enable two independent calibration adjustments on the same module, reducing BOM count and assembly cost.
Recomendado
Resumen de productos recomendados
Datos de referencia de ingeniería para MCP4242-502E/UN — comparación, orientación de diseño e información de cumplimiento.
Guía de selección
Comparación con alternativas
| Parámetro | Este producto | MCP4242-103E/UN | MCP4242-503E/UN | MCP4242-104E/UN | MCP4242T-502E/UN | MCP4252-502E/UN |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | MSOP-10 (UN) | MSOP-10 (UN) - same | MSOP-10 (UN) - same | MSOP-10 (UN) - same | MSOP-10 (UN) - same | MSOP-10 (UN) - same |
| End-to-End Resistance | 5 kΩ | 10 kΩ | 50 kΩ | 100 kΩ | 5 kΩ | 5 kΩ |
| Resolution | 7-bit (129 taps) | 7-bit (129 taps) | 7-bit (129 taps) | 7-bit (129 taps) | 7-bit (129 taps) | 8-bit (257 taps) |
| Number of Pots | 2 (Dual) | 2 (Dual) | 2 (Dual) | 2 (Dual) | 2 (Dual) | 2 (Dual) |
| Interface | SPI | SPI | SPI | SPI | SPI | SPI |
| 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 | 2.7 V to 5.5 V |
| Operating Temperature | -40°C to +125°C | -40°C to +125°C | -40°C to +125°C | -40°C to +125°C | -40°C to +125°C | -40°C to +125°C |
| Non-Volatile Memory | Yes (EEPROM) | Yes (EEPROM) | Yes (EEPROM) | Yes (EEPROM) | Yes (EEPROM) | Yes (EEPROM) |
Diferenciadores clave
- 5 kΩ end-to-end resistance suits low-impedance signal paths (frente a MCP4242-103E/UN)
- 7-bit resolution matches 8-bit ADC step quantization (frente a MCP4252-502E/UN)
- Same 10-MSOP package across entire resistance family (frente a MCP4242-104E/UN)
Notas de diseño
Decouple VDD (pin on VDD side of MSOP-10, see datasheet) with a 0.1 µF ceramic capacitor placed within 3 mm of the supply pin. The MCP4242-502E/UN draws less than 1 mA quiescent current, but EEPROM write cycles (tWC ≈ 5 ms) cause brief higher current peaks. A bulk decoupling capacitor of 1 µF to 10 µF on the supply rail improves write-cycle reliability, especially when sharing the supply with noisy digital loads.
Keep the analog wiper traces (P0A, P0W, P0B, P1A, P1W, P1B) routed away from SPI clock and data lines to avoid capacitive coupling that injects digital noise into the wiper node. Place a guard ground trace between analog wiper routing and the SPI bus for high-precision applications. The 75 Ω wiper resistance and switch-capacitance of the CMOS switches make the wiper node sensitive to fast edges on adjacent digital traces.
Avoid operating the wiper near either end terminal (taps 0 or 128) where the on-resistance of the CMOS switches introduces the largest nonlinearity. For linear transfer functions, restrict the operating range to taps 16-112 (the 12.5%-87.5% window) where end-resistance effects are negligible. Also, do not exceed the absolute maximum terminal voltage of VDD + 0.3 V or VSS - 0.3 V on any potentiometer terminal, or the internal ESD diodes will forward-conduct and may latch the device.
The MCP4242-502E/UN's 5 kΩ end-to-end resistance is best driven by low-impedance sources (op-amp output, low-ohm voltage reference). When using a high-impedance source, the wiper resistance (75 Ω typical) introduces a series error of up to ~1.5% of full-scale (75 Ω / 5000 Ω). For critical applications, calibrate the wiper setting at production test to remove this gain error, or use the 4-wire Kelvin connection technique available on the rheostat configuration.
Información de cumplimiento
RoHS and REACH compliant per Microchip product page. Lead-free (Pb-free) MSL-1 rated. Not AEC-Q100 qualified; for automotive applications consider AEC-Q100-qualified alternatives within Microchip's digiPOT portfolio.
