Diodes Incorporated PT7M8218B18TAE

Overview

PT7M8218B18TAE from Pericom Semiconductor is a 300mA, high-PSRR low-dropout linear regulator with 2.8V fixed output, ±2% initial accuracy, 150mV dropout at 150mA, and 75dB PSRR at 1kHz. 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. It powers noise-sensitive analog rails in portable RF front-ends.

For engineers reviewing the PT7M8218B18TAE datasheet, PT7M8218B18TAE pinout, PT7M8218B18TAE application, or PT7M8218B18TAE equivalent, key selection criteria include dropout voltage under load, PSRR at baseband frequencies, quiescent current in active/standby modes, EN pin logic polarity, and SC70-5L/SOT23-5L package compatibility with space-constrained PCB layouts.

Technical Context

The PT7M8218B18TAE uses a P-channel MOSFET pass element controlled by an internal error amplifier comparing output voltage against a precision bandgap reference. Its integrated phase compensator enables stability with 0.47µF X5R/X7R ceramic capacitors on both input and output.

EN pin is high-active (logic HIGH enables regulation), with V_ENH ≥1.2V and V_ENL ≤0.3V. The device features auto-discharge via a 50Ω internal switch between VOUT and GND when disabled, reducing residual voltage hold-up in power sequencing.

Key Specifications

Pinout & Package

PT7M8218B18TAE is packaged in lead-free, green-compliant SOT23-5L (JEDEC MO-178C/AA) with 0.95mm pitch, footprint-compatible with industry-standard 5-pin SOT-23 layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with XC6219B282MR-G and RT9193-28GB, PT7M8218B18TAE delivers superior PSRR (75dB vs. ≤70dB), lower dropout (150mV vs. ≥120mV), and integrated auto-discharge - making it optimal for RF and fast-sequencing portable systems where noise, efficiency, and power-state fidelity are critical.

Availability

PT7M8218B18TAE is available at Aetrix Electronics and suitable for mobile RF front-ends, portable audio codecs, and Bluetooth SoC core rails requiring stable component supply, consistent parametric performance, and RoHS-compliant packaging.

Supply support for PT7M8218B18TAE 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.

PT7M8218 belongs to Pericom's precision LDO family targeting portable RF and imaging applications, designed specifically for low-noise, high-PSRR operation with minimal external components and robust thermal/current protection.

FAQ

What is the maximum input voltage rating for PT7M8218B18TAE?

The absolute maximum input voltage is +6.0V, but the recommended operating range is 1.7V to 5.5V. Exceeding 5.5V risks permanent damage even briefly; operation above 6.0V violates absolute maximum ratings and may trigger irreversible junction failure. Always use input filtering and clamping if transient overvoltage is possible.

Does PT7M8218B18TAE require an input capacitor?

Yes - a 0.47µF X5R/X7R ceramic capacitor is required on VIN, placed within 2mm of pins 1 and 2. This stabilizes input impedance, suppresses high-frequency noise, and prevents oscillation during load transients. Omitting it causes instability and can result in output overshoot or thermal shutdown under dynamic loads.

Can PT7M8218B18TAE be used with tantalum output capacitors?

No - the internal compensation is optimized exclusively for 0.47µF ceramic capacitors with ESR ≤100mΩ. Tantalum capacitors have higher ESR and different frequency response, which destabilizes the control loop and may cause sustained oscillation or excessive output ripple. Only X5R/X7R ceramics meeting the datasheet's ESR and capacitance tolerance are validated.

What happens to VOUT when EN is pulled low?

When EN is driven ≤0.3V, regulation stops immediately, and the internal 50Ω discharge switch connects VOUT to GND. This discharges the output capacitor to <100mV within 1ms, eliminating residual voltage that could interfere with downstream logic states or cause latch-up in powered-down circuitry.