Diodes Incorporated PT7M8218B28CEX

Overview

PT7M8218B28CEX 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 phones, digital cameras, and portable audio devices.

For engineers reviewing the PT7M8218B28CEX datasheet, PT7M8218B28CEX pinout, PT7M8218B28CEX application, or PT7M8218B28CEX equivalent, key selection criteria include dropout voltage under load, PSRR performance at baseband frequencies, EN pin logic polarity (high-active), SC70-5L package thermal limitations, and compatibility with low-ESR ceramic capacitors in space-constrained portable designs.

Technical Context

The PT7M8218B28CEX uses a P-channel MOSFET pass element controlled by an internal error amplifier and reference voltage circuit, enabling stable regulation with minimal headroom. Its internal phase compensation ensures stability with 0.47µF X5R/X7R ceramic capacitors on both input and output.

Enable control is high-active (EN ≥1.2V), with sub-1µA standby current when disabled. Protection includes foldback current limiting (400mA typical trip) and thermal shutdown at 170°C with 20°C hysteresis - critical for sustained operation in thermally dense handheld enclosures.

Key Specifications

Pinout & Package

PT7M8218B28CEX is packaged in SC70-5L (JEDEC MO-203B/AA), a 2.2mm × 1.35mm surface-mount package with 0.65mm pitch, optimized for ultra-compact 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, PT7M8218B28CEX delivers superior PSRR and lower dropout while retaining high-active EN and auto-discharge - making it optimal for RF-adjacent and battery-life-critical portable applications where noise rejection and fast sequencing matter.

Availability

PT7M8218B28CEX is available at Aetrix Electronics and suitable for mobile phone baseband power, digital camera image sensor bias, and portable audio DAC supply requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for PT7M8218B28CEX 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 2016 acquisition.

The PT7M8218 belongs to Pericom's precision LDO family designed specifically for noise-sensitive portable applications demanding low dropout, high PSRR, and minimal quiescent current in ultra-small packages.

FAQ

What is the maximum allowable input voltage for PT7M8218B28CEX?

The absolute maximum input voltage is +6.0V, but continuous operation must remain within the recommended 1.7V to 5.5V range. Exceeding 5.5V risks permanent damage per the Absolute Maximum Ratings table; operation above 5.5V-even briefly-may trigger latch-up or degrade long-term reliability without immediate failure.

Can PT7M8218B28CEX operate with a 1µF output capacitor instead of 0.47µF?

Yes - the device remains stable with 1µF ceramic capacitors, though the datasheet specifies minimum stability with 0.47µF X5R/X7R types. Larger values improve transient response and reduce output ripple, but do not affect regulation accuracy or PSRR; ensure ESR stays below 10mΩ to maintain phase margin.

Is the NC pin (Pin 4) required to be grounded?

No - Pin 4 is internally unconnected and may be left floating, but grounding it improves mechanical anchoring and reduces potential antenna effects in RF-dense layouts. The datasheet explicitly states "leaving it open is also acceptable," so grounding is a layout best practice, not an electrical requirement.

Does PT7M8218B28CEX support reverse current blocking?

No - the device lacks integrated reverse-current protection. When VIN falls below VOUT, current can flow backward from VOUT to VIN through the P-MOSFET body diode. For applications requiring reverse blocking (e.g., battery backup paths), an external Schottky diode or ideal diode controller must be added in series with VIN.