Microchip Technology RE46C119S16TF

Overview

RE46C119S16TF from Microchip Technology (via R&E International) is a mixed-signal IC integrating a 3V low-dropout regulator, a 12V switched-capacitor boost converter, and dual high-voltage piezoelectric horn drivers (HORNS/HORNB). It features low-battery detection (LBAT), power-good monitoring (PG), and bidirectional interconnect logic (IO1/IO2/IODIR) for multi-unit alarm systems. Designed for battery-powered safety devices, it delivers 12.7V VPOS output at −16mA with 99% voltage efficiency and draws only 6.5µA quiescent current when idle.

For engineers reviewing the RE46C119S16TF datasheet, RE46C119S16TF pinout, RE46C119S16TF application, or RE46C119S16TF equivalent, key selection considerations include its integrated 3V/12V dual-output architecture, open-drain PG and LBAT analog outputs, bi-directional interconnect capability, and SOIC-16 package compatibility with smoke/CO detector BOMs requiring low-power horn drive and microprocessor regulation.

Technical Context

The RE46C119S16TF implements a charge-pump-based 12V boost regulator using an internal 150kHz oscillator and external fly capacitors (VCAP+/VCAP−), delivering regulated VPOS output independent of VDD fluctuations between 6V–12V. Its LDO regulator provides stable 3V (±150mV line/load regulation) to microcontrollers while incorporating overvoltage clamping (3.7–4.3V) and brownout protection.

Low-battery detection operates via resistor-divider-sensed VDD scaling, producing an analog LBAT output proportional to supply voltage (0.17–0.23×VDD trip threshold). Horn enable (HRNEN) controls simultaneous activation of both horn drivers and the boost converter, while interconnect logic enables daisy-chained communication between multiple RE46C119S16TF units using TTL-compatible IO1/IO2 with direction control via IODIR.

Key Specifications

Pinout & Package

RE46C119S16TF is housed in a 16-pin SOIC package (S16TF suffix), with 1.27mm pitch, 10.3mm × 7.5mm body, and RoHS-compliant Pb-free finish. Thermal pad not present; standard SOIC thermal performance applies.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar piezoelectric horn driver and dual-rail regulator applications.

Compared with MAX680CPA+ and TPS61040DRVR, the RE46C119S16TF uniquely integrates 3V regulation, 12V charge-pump boosting, dual piezo drivers, LBAT analog output, PG status, and interconnect logic in one SOIC-16 package-reducing total solution size by >60% and eliminating six external components typical in discrete implementations.

Availability

RE46C119S16TF is available at Aetrix Electronics and suitable for smoke detectors, CO detectors, and personal security alarms requiring stable component supply, long-term lifecycle support, and RoHS-compliant manufacturing.

Supply support for RE46C119S16TF 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 semiconductor manufacturer specializing in microcontrollers, analog devices, and interface ICs, with ISO/TS-16949-certified wafer fabrication and design centers.

The RE46C119S16TF belongs to Microchip's R&E International legacy safety and alarm product line, engineered specifically for UL-listed residential fire and gas detection systems requiring integrated power management and audible alert generation.

FAQ

What is the maximum continuous output current capability of the RE46C119S16TF horn drivers?

The RE46C119S16TF supports up to 50mA continuous operating current on the VPOS, HORNS, and HORNB outputs. Each horn driver is rated for −16mA load at specified VPOS voltage, with typical Ron optimized for low-loss piezoelectric actuation. Exceeding 50mA risks thermal shutdown or permanent damage per Absolute Maximum Ratings.

Does the RE46C119S16TF require external components to operate its 3V regulator?

Yes, the RE46C119S16TF requires an external output capacitor of at least 10µF (low-ESR ceramic recommended) between VREG and VSS to stabilize the LDO control loop. Without this capacitor, the 3V regulator may oscillate or fail to regulate properly. No additional resistors or feedback networks are needed-the VREG output is internally fixed at 3.0V.

How does the interconnect logic (IO1, IO2, IODIR) function in multi-unit alarm systems?

The RE46C119S16TF interconnect logic allows up to eight units to be daisy-chained: IODIR configures IO1 and IO2 as inputs or outputs, enabling master-slave signaling. When one unit triggers an alarm, its IO1 drives high, propagating the signal through adjacent IO2 pins. This eliminates need for external bus controllers or protocol stacks in compliant smoke/CO detector networks.

Can the RE46C119S16TF's 12V boost output (VPOS) be used for loads other than piezoelectric horns?

Yes, the VPOS output of the RE46C119S16TF can power any 12V-compatible load drawing ≤50mA, such as small solenoids, LED arrays, or analog front-end circuitry-provided the load does not introduce excessive ripple or back-EMF. However, the internal charge pump is optimized for capacitive piezo loads; inductive loads require external flyback protection diodes.

What is the purpose of the FEED pin on the RE46C119S16TF, and what voltage range does it accept?

The FEED pin on the RE46C119S16TF provides feedback path for closed-loop horn drive amplitude control. It accepts −10V to +22V input, allowing direct connection to piezoelectric element terminals to sense mechanical resonance or distortion. This enables adaptive tone shaping and prevents overdriving fragile piezo transducers in safety-critical applications.