Microchip Technology RE46C104S14TF

Overview

RE46C104S14TF from Microchip Technology (via R&E International) is a piezoelectric horn driver with integrated charge-pump voltage converter, designed to drive self-oscillating or directly driven piezo horns from 4.0–8.0 V supply while delivering up to 8.7 V output swing and 30 mA continuous output current. It features active-high HRNEN and CPMPEN controls, operates at 0–50°C, and targets low-power audible alarm systems.

For engineers reviewing the RE46C104S14TF datasheet, RE46C104S14TF pinout, RE46C104S14TF application, or RE46C104S14TF equivalent, key selection criteria include its 16 kHz charge pump oscillator frequency, 95–99% voltage conversion efficiency, dual horn outputs (HORNS/HORNB), VPOS rail generation, and FEED input tolerance to –10 V to +22 V for feedback-based oscillation control.

Technical Context

The RE46C104S14TF integrates a CMOS-based oscillator and logic block that drives internal level shifters to generate complementary high-voltage outputs for piezo horn excitation. Its charge pump uses external capacitors (C1/C2 = 10 µF) to double Vdd, enabling rail-to-rail horn drive from Vss to ~2×Vdd.

Feedback control via the FEED pin supports self-oscillating piezo configurations, while independent HRNEN and CPMPEN pins allow precise timing of horn activation and charge pump enablement-critical for minimizing quiescent current (100 nA standby) in battery-powered smoke and CO detectors.

Key Specifications

Pinout & Package

RE46C104S14TF is housed in a 14-pin SOIC package (SOIC-14, 150 mil width) with exposed pad not present; pin 1 is top-left corner marked dot.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar piezoelectric horn driver applications.

Compared with DRV8837 and ADP1613, the RE46C104S14TF uniquely integrates piezo-specific functions-including FEED-based self-oscillation, dual complementary outputs, and ultra-low standby current-making it a purpose-built solution for battery-operated audible alarms where integration, efficiency, and longevity are critical.

Availability

RE46C104S14TF is available at Aetrix Electronics and suitable for smoke detectors, CO detectors, personal security products, and electronic toys requiring stable component supply across long-lifecycle consumer safety applications.

Supply support for RE46C104S14TF includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Microchip Technology Inc. is a global provider of microcontrollers, analog components, and connectivity solutions, headquartered in Chandler, Arizona, with ISO/TS-16949 certified manufacturing facilities.

The RE46C104S14TF belongs to Microchip's R&E International piezo driver product line, engineered specifically for ultra-low-power audible alarm systems in life-safety and portable electronics applications.

FAQ

What is the function of the FEED pin on the RE46C104S14TF?

The FEED pin on the RE46C104S14TF accepts feedback from a resonant piezoelectric element to sustain self-oscillation, enabling tone generation without external timing components. It supports input voltages from –10 V to +22 V and is essential for applications like smoke alarms where consistent acoustic frequency and low component count are critical. The RE46C104S14TF uses this signal to close the oscillator loop internally.

Can the RE46C104S14TF drive a piezo horn directly without external components?

No-the RE46C104S14TF requires two external 10 µF capacitors (CAP+ and CAP−) for charge pump operation and typically needs a series resistor (e.g., 1.5 MΩ) on the FEED pin for stable self-oscillation. Direct drive without these components results in insufficient output voltage or failure to start oscillation. The RE46C104S14TF datasheet specifies C1=C2=10 µF and R1=1.5 MΩ as minimum functional configuration.

What is the maximum continuous output current rating for the RE46C104S14TF?

The RE46C104S14TF supports up to 30 mA continuous output current on each of HORNS, HORNB, and VPOS pins, as specified in Absolute Maximum Ratings. This rating applies under steady-state conditions at TA = 25°C and ensures reliable operation with standard 3–5 kHz piezo transducers. Exceeding 30 mA may cause thermal shutdown or permanent damage to the RE46C104S14TF.

How does the CPMPEN pin affect power consumption in the RE46C104S14TF?

The CPMPEN pin on the RE46C104S14TF enables or disables the internal charge pump oscillator. When held low, the charge pump is inactive, reducing supply current to 100–500 nA (standby mode). When driven high, the pump activates and draws ~200–500 µA (operating mode). This control allows dynamic power gating-essential for extending battery life in intermittently active devices such as CO detectors using the RE46C104S14TF.

Is the RE46C104S14TF RoHS compliant and available in lead-free packaging?

Yes, the RE46C104S14TF is available in RoHS-compliant, Pb-free packaging per manufacturer documentation. R&E International (a Microchip subsidiary) explicitly lists "RoHS Compliant Pb Free Packaging" among the device features. The SOIC-14 package meets JEDEC J-STD-020 moisture sensitivity level (MSL) 1 and is compatible with standard reflow profiles for lead-free assembly.