LM4132CMF-3.3

Voltage Reference Overview

The LM4132CMF-3.3 is a precision low-dropout voltage reference from Texas Instruments, providing a fixed output of 3.3 V. It operates within an input voltage range of VREF + 400 mV to 5.5 V and delivers up to 20 mA of load current. The device features an initial accuracy of ±0.2% and a temperature coefficient of 20 ppm/°C across the -40°C to +125°C junction temperature range. It consumes 60 µA of supply current, reducing to 3 µA in shutdown mode via the enable pin. Packaged in a compact SOT-23 (5-pin) format, it requires only a single input capacitor for stability.

Voltage Reference Feature Summary

• Utilizes CMOS band-gap architecture with EEPROM registers for package-level programming to correct curvature and accuracy shifts during assembly.
• Features an enable pin that allows switching between normal operation and a low-power shutdown mode with minimal quiescent current consumption.
• Capable of sourcing high load currents without requiring an output capacitor or buffer amplifier, simplifying circuit design.

Voltage Reference Applications

• Instrumentation and process control systems
• Data acquisition systems
• Portable battery-powered equipment
• Precision regulators

Voltage Reference Procurement Notes

Verify the specific grade suffix (e.g., C for ±0.2%) against the required accuracy specifications. Confirm the package type matches the target PCB footprint. Check for automotive qualification requirements, as standard and Q1 grades have different availability and testing criteria. Ensure the ordering suffix aligns with the desired packaging configuration.

Voltage Reference Selection Notes

Select this component when a stable 3.3 V reference is needed in space-constrained designs. The SOT-23 package offers a small form factor suitable for portable devices. Consider the 20 ppm/°C temperature coefficient for applications requiring moderate thermal stability. The ability to drive up to 20 mA makes it suitable for direct interfacing with ADCs or DACs without additional buffering.

Voltage Reference Part Context

The LM4132 family includes various voltage options ranging from 1.8 V to 4.096 V, available in multiple accuracy grades (A through E). The CMF variant specifically denotes the 3.3 V output version in the SOT-23 package. This series competes with laser-trimmed bipolar references but utilizes cost-effective CMOS technology to achieve comparable performance levels.

Voltage Reference FAQ

Is an output capacitor required for the LM4132CMF-3.3?

No, the LM4132CMF-3.3 is stable with low-ESR ceramic capacitors and does not require an output capacitor or buffer amplifier for proper operation.

How is the shutdown mode activated?

Shutdown mode is activated by pulling the Enable (EN) pin to a logic low level (below 35% of VIN), which reduces the supply current to approximately 3 µA.