Diodes Incorporated PT7M8218B20TAEX

Overview

PT7M8218B20TAEX from Pericom Semiconductor is a 2.8V fixed-output, 300mA low-dropout linear regulator featuring 150mV dropout at 150mA, ±2% initial output accuracy, 75dB PSRR at 1kHz, and 36µA quiescent current. It operates from 1.7V to 5.5V input, supports 0.47µF ceramic output capacitors, and integrates thermal shutdown, current limiting, and auto output discharge - deployed in mobile phone baseband power rails and portable camera sensor supplies.

For engineers reviewing the PT7M8218B20TAEX datasheet, PT7M8218B20TAEX pinout, PT7M8218B20TAEX application, or PT7M8218B20TAEX equivalent, key selection criteria include dropout voltage under 150mA load, PSRR performance at 1kHz, EN pin logic polarity (high-active), SC70-5L/SOT23-5L package compatibility, and ±2% output accuracy across –40°C to +85°C.

Technical Context

The PT7M8218B20TAEX uses a P-channel MOSFET pass element with internal phase compensation optimized for stability with 0.47µF X5R/X7R ceramic capacitors. Its error amplifier compares a resistive-divided output against a precision bandgap reference to regulate 2.8V output within ±2% initial tolerance.

Enable control is high-active (EN ≥1.2V), with standby current ≤1µA when disabled. Protection includes foldback current limiting (400mA typical) and thermal shutdown at 170°C with 20°C hysteresis - critical for sustained operation in space-constrained portable devices.

Key Specifications

Pinout & Package

PT7M8218B20TAEX is packaged in lead-free, RoHS-compliant SOT23-5L (JEDEC MO-178C/AA) - 2.9mm × 1.6mm footprint, 0.95mm pitch, 1.2mm height - suitable for high-density portable PCB layouts.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar LDO regulator applications.

Compared with XC6206P282MR and RT9193-28GB, PT7M8218B20TAEX uniquely balances 75dB PSRR, 150mV dropout, and auto-discharge in a 5-pin SOT23 package - making it optimal for noise-sensitive, battery-powered applications requiring precise sequencing and minimal residual voltage.

Availability

PT7M8218B20TAEX is available at Aetrix Electronics and suitable for mobile phones, digital cameras, PDAs, and MP3 players requiring stable component supply, consistent parametric performance, and long-term production continuity.

Supply support for PT7M8218B20TAEX 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

Pericom Semiconductor (now part of Diodes Incorporated) specialized in high-performance interface, timing, and power management ICs for communications and consumer electronics before its 2017 acquisition.

The PT7M8218 series was designed specifically for ultra-low-noise, high-PSRR power regulation in space-constrained portable devices - emphasizing ceramic capacitor compatibility, sub-1µA shutdown, and ±2% accuracy across temperature.

FAQ

What is the correct capacitor type and value for stable operation?

PT7M8218B20TAEX requires a 0.47µF X5R or X7R ceramic capacitor on both VIN and VOUT pins, placed within 2mm of the device. These low-ESR capacitors ensure loop stability, minimize output ripple, and meet the 75dB PSRR specification. Tantalum or electrolytic capacitors are not recommended due to higher ESR and potential instability.

Does the NC pin require a specific connection?

Pin 4 (NC) is internally unconnected but should be tied to GND for mechanical reinforcement and improved EMI performance. Leaving it floating is electrically acceptable per datasheet, but grounding reduces parasitic antenna effects in high-frequency portable designs and improves solder joint reliability.

How does the EN pin behave during power-up and shutdown?

The EN pin is high-active with 1.2V threshold. During power-up, VOUT ramps only after EN exceeds 1.2V; during shutdown, pulling EN ≤0.3V disables the regulator and activates the 50Ω internal discharge path, discharging VOUT to <0.1V within ~1ms (with 0.47µF Cout). No external pull-up is required if driven actively.

Can PT7M8218B20TAEX be used with input voltages below 1.7V?

No - the absolute minimum input voltage is 1.7V per datasheet specifications. Operation below this violates the recommended operating conditions and risks failure to regulate, increased dropout, or undefined behavior. For sub-1.7V applications, consider alternative LDOs rated for 0.9V–1.5V input, such as the Torex XC6210 series.