Diodes Incorporated PT7M8218B09CEX

Overview

PT7M8218B09CEX from Pericom Semiconductor is a 300mA, high-PSRR low-dropout linear regulator with 0.9V fixed output voltage, 150mV dropout at 150mA (V_OUT=2.8V), ±2% initial accuracy, and 75dB PSRR at 1kHz. It operates from 1.7V to 5.5V input, supports 0.47µF ceramic output capacitors, and delivers stable power in space-constrained portable RF and digital baseband circuits.

For engineers reviewing the PT7M8218B09CEX datasheet, PT7M8218B09CEX pinout, PT7M8218B09CEX application, or PT7M8218B09CEX equivalent, key selection criteria include guaranteed 300mA load capability under low-input-voltage conditions, auto output discharge for system-level power sequencing, thermal shutdown at 170°C, and compatibility with SC70-5L footprint for ultra-compact PCB layouts.

Technical Context

The PT7M8218B09CEX uses a P-channel MOSFET pass element controlled by an internal error amplifier and reference voltage source, enabling low dropout and high DC accuracy without external compensation. Its internal phase compensator ensures stability with 0.47µF X5R/X7R ceramic capacitors on both input and output.

EN pin logic is high-active (V_ENH ≥1.2V), enabling precise power-domain control in multi-rail systems; the NC pin (Pin 4) is internally unconnected but recommended tied to GND for noise immunity. Thermal shutdown hysteresis of 20°C prevents oscillation during overload recovery.

Key Specifications

Pinout & Package

PT7M8218B09CEX is packaged in SC70-5L (JEDEC MO-203B/AA), a 2.2mm × 1.35mm × 0.9mm surface-mount package with 0.65mm pitch, optimized for high-density portable PCBs.

Key Features

Applications

Equivalent & Alternatives

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

Compared with XC6206P092MR and RT9193-09GB, PT7M8218B09CEX uniquely combines high PSRR (75dB), auto discharge, and SC70-5L packaging-making it optimal for RF-critical, space-constrained, and power-sequenced designs where noise rejection and fast turn-off are non-negotiable.

Availability

PT7M8218B09CEX is available at Aetrix Electronics and suitable for mobile baseband power, RF transceiver bias, digital camera ISP core, and wearable sensor hub applications requiring stable component supply, consistent parametric performance, and long-term lifecycle support.

Supply support for PT7M8218B09CEX 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 analog and mixed-signal ICs for timing, connectivity, and power management in communications and computing systems.

The PT7M8218 series was designed specifically for portable wireless devices demanding ultra-low-noise, high-PSRR, and compact-footprint LDO regulation in multi-rail architectures.

FAQ

What is the minimum input voltage required for stable 0.9V output at 300mA?

The PT7M8218B09CEX requires VIN ≥ VOUT + VDROPOUT. With 150mV typical dropout at 150mA and confirmed 180mV max for VOUT ≤2.7V, the minimum input is 1.08V. However, the absolute minimum operating VIN is specified as 1.7V across all conditions - this ensures full 300mA capability, thermal margin, and PSRR performance per datasheet limits.

Can the NC pin (Pin 4) be left floating in production designs?

Yes, Pin 4 is internally unconnected and may be left floating per datasheet guidance. However, tying it to GND is recommended to reduce susceptibility to board-level noise coupling and improve EMI robustness - especially in RF-dense layouts where parasitic capacitance could otherwise modulate internal node potentials.

Does the 0.47µF output capacitor requirement apply to all ceramic dielectrics?

No - only X5R and X7R grade ceramics are validated for stability. Y5V and Z5U types exhibit excessive capacitance shift with DC bias and temperature, risking loop instability and oscillation. The 0.47µF value is the minimum; larger values improve transient response but require verification against phase margin using the internal compensation network.

How does the auto output discharge function interact with external pull-down resistors?

The internal 50Ω discharge path activates only when EN = low. If an external pull-down resistor (e.g., 10kΩ) is present on VOUT, it forms a parallel discharge path that dominates the 50Ω internal path - reducing effective discharge resistance and accelerating VOUT decay. This is acceptable but must be accounted for in power-sequencing timing analysis.