Diodes Incorporated PAM3101DAB285

Overview

PAM3101DAB285 from Diodes Incorporated is a 2.85V fixed-output, 300mA low-dropout CMOS linear regulator with active-high enable, bypass pin, and DFN1.6×1.6-6L package. It delivers 180mV dropout at 300mA, 70dB PSRR at 1kHz, ±2% output accuracy, 65µA quiescent current, and thermal/short-circuit protection - optimized for noise-sensitive battery-powered audio and RF subsystems in portable electronics.

For engineers reviewing the PAM3101DAB285 datasheet, PAM3101DAB285 pinout, PAM3101DAB285 application, or PAM3101DAB285 equivalent, key selection criteria include dropout voltage under load, PSRR vs. frequency, EN logic polarity, BYP capacitor requirement (10nF), and thermal resistance (θJA = 175°C/W) in the DFN1.6×1.6 package.

Technical Context

The PAM3101DAB285 integrates a P-channel MOSFET pass transistor (R_DS(on) ≈ 0.75Ω) enabling ultra-low ground current across load conditions. Its internal bandgap reference and error amplifier deliver ±2% output voltage accuracy over line, load, and temperature (–40°C to +85°C).

It features an active-high enable input (V_TH = 1.5V min), a dedicated BYP pin requiring a 10nF capacitor to GND for noise filtering, and built-in protections: current limit (~400mA), short-circuit foldback, and thermal shutdown at +150°C with +30°C hysteresis.

Key Specifications

Pinout & Package

DFN1.6×1.6-6L package: 1.6mm × 1.6mm body, 0.5mm pitch, exposed thermal pad (GND-connected), moisture sensitivity level 1, RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar low-noise LDO applications.

Compared with AP2125K-2.85TRG1 and MCP1700T-285E/TT, the PAM3101DAB285 uniquely combines BYP-enabled ultra-low noise, 180mV dropout, and active-high EN in a thermally efficient DFN package - making it optimal for compact, noise-critical RF/audio designs where all three features are concurrently required.

Availability

PAM3101DAB285 is available at Aetrix Electronics and suitable for Bluetooth earphones, portable medical sensors, and industrial handheld scanners requiring stable component supply, long-lifecycle support, and guaranteed DFN1.6×1.6-6L packaging.

Supply support for PAM3101DAB285 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

Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, specializing in high-reliability power management, signal integrity, and protection solutions for consumer, industrial, and automotive markets.

The PAM3101 belongs to Diodes' high-PSRR, low-IQ LDO family designed specifically for noise-sensitive portable electronics - emphasizing dropout performance, thermal robustness, and integration of enable/bypass functions in miniature packages.

FAQ

What is the minimum input voltage required for PAM3101DAB285 to regulate 2.85V at 300mA?

The minimum input voltage is determined by dropout: VIN(MIN) = VO + VDROP. At 300mA, VDROP ≤ 230mV (max for VO ≥ 3.3V; extrapolated to ~215mV for 2.85V). Thus, VIN(MIN) ≈ 3.065V. Operation below this causes output droop or dropout. Input must also stay within 2.5V–5.5V absolute range.

Can the BYP pin be left unconnected?

No. The BYP pin must be connected to GND via a 10nF ceramic capacitor to achieve specified 50µV_RMS output noise and 70dB PSRR. Leaving it open degrades noise performance and may cause instability in high-frequency noise rejection. The internal 200kΩ resistor forms a low-pass filter only when the capacitor is present.

Is PAM3101DAB285 pin-compatible with other PAM3101 variants?

No. PAM3101DAB285 uses the DFN1.6×1.6-6L package with pinout EN/NC/VIN/VOUT/NC/GND. Other variants (e.g., SOT-23-5 or SC-70-5) have different pin counts, assignments, and enable logic defaults (floating vs. pull-high). PCB layout and firmware control must be verified per variant - not drop-in replaceable.

Does PAM3101DAB285 require an input capacitor?

Yes. A minimum 1µF ceramic capacitor is required on VIN, placed within 0.5 inch of the device. Larger values improve PSRR and transient response; low-ESR ceramics are mandatory. Without it, the regulator may oscillate or fail to reject input ripple, especially from switching supplies feeding the LDO.