Microchip TC1262-3VDBTR 500mA Low-Dropout Voltage Regulator: Datasheet and Application Circuit Design
In the realm of power management for modern electronic devices, the Low-Dropout (LDO) voltage regulator remains a fundamental component, prized for its simplicity, low noise, and fast transient response. The Microchip TC1262-3VDBTR exemplifies these qualities, offering a robust solution for applications requiring a stable 3.3V supply with currents up to 500mA. This article delves into the key specifications from its datasheet and outlines a standard application circuit design.
Key Datasheet Specifications and Features
The TC1262 is a CMOS LDO regulator designed for high-performance, battery-powered applications. The -3VDBTR variant provides a fixed 3.3V output. Its defining characteristic is an extremely low dropout voltage—typically 85mV at 300mA and a maximum of 250mV at 500mA. This efficiency is critical for extending battery life, as it allows the regulator to continue providing a stable output even as the input voltage dips very close to the output level.
Beyond its low dropout, the TC1262 boasts several other noteworthy features:
Low Quiescent Current: With a typical ground current of only 85µA, it minimizes the drain on the power source when the load is light.
Excellent Load and Line Regulation: Ensures a stable 3.3V output despite fluctuations in input voltage or output current.
Protection Circuits: The IC includes built-in over-current and over-temperature protection, safeguarding both the regulator and the downstream circuitry from damage during fault conditions.
Low Output Noise: The CMOS design and the recommended use of a small bypass capacitor on the feedback network contribute to a clean output voltage, which is vital for noise-sensitive components like analog sensors and RF circuits.
Stable with Low-ESR Ceramic Capacitors: This modern feature simplifies design and reduces the bill of materials cost compared to older LDOs that required bulky tantalum capacitors for stability.
Standard Application Circuit Design
Implementing the TC1262-3VDBTR is remarkably straightforward, a key reason for its popularity. The basic application circuit requires only two external components: input and output capacitors.
1. Input Capacitor (C_IN): A 1µF ceramic capacitor placed between the input pin (VIN) and ground (GND) is recommended. This capacitor improves the circuit's transient response and helps suppress any incoming noise or ripple on the input supply line. It should be located as close as possible to the IC's pins.
2. Output Capacitor (C_OUT): A 2.2µF ceramic capacitor between the output pin (VOUT) and ground is required for stability. This capacitor ensures the feedback loop remains stable under all load conditions. Like the input capacitor, it should be placed close to the regulator to minimize parasitic inductance.
The TC1262-3VDBTR is offered in a space-saving 3-pin SOT-223 package, making it suitable for compact PCB designs. The tab on the package is connected to GND, which aids in heat dissipation. For high-current operation near the 500mA maximum, ensuring adequate PCB copper pour for the GND connection is essential to act as a heatsink.
The Microchip TC1262-3VDBTR is a highly efficient and reliable LDO regulator, perfectly suited for a wide array of applications from consumer electronics and IoT devices to industrial controls. Its exceptional combination of low dropout voltage, minimal quiescent current, and robust protection features makes it an outstanding choice for designers seeking to maximize performance and battery life in 3.3V systems.
Keywords:
Low-Dropout (LDO) Voltage Regulator
500mA Output Current
3.3V Fixed Output
Low Quiescent Current
Ceramic Capacitor Stable
