Diodes Incorporated AP7115-18SEG-7

Overview

AP7115-18SEG-7 from Diodes Incorporated is a 150mA fixed-output (1.8V) low-dropout linear regulator in SOT353 package, featuring 200mV dropout at full load, ±2% output voltage accuracy, and 50µA quiescent current. It integrates thermal shutdown, current limit, and enable control for battery-powered handheld devices requiring stable low-voltage rail generation.

For engineers reviewing the AP7115-18SEG-7 datasheet, AP7115-18SEG-7 pinout, AP7115-18SEG-7 application, or AP7115-18SEG-7 equivalent, key selection criteria include dropout performance at 150mA, EN-controlled power sequencing, BP-bypass noise reduction capability, and SOT353 thermal resistance (θJA = 337°C/W) in space-constrained designs.

Technical Context

The AP7115-18SEG-7 uses a PMOS pass element with bandgap reference and error amplifier to regulate output voltage. Its enable input (EN) provides active-high logic control, while the BP pin accepts a 0.1µF capacitor to suppress reference noise and improve output voltage stability.

Thermal shutdown activates at +150°C junction temperature, with automatic recovery after ~30°C cooldown. Current limiting is implemented via gate-voltage monitoring of the PMOS transistor, delivering 200–250mA typical short-circuit protection independent of input voltage.

Key Specifications

Pinout & Package

SOT353 (5-pin, 2.15mm × 2.10mm × 0.90mm) surface-mount package with exposed pad not electrically connected; optimized for low-profile portable PCBs.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AP7315-18SG-7, the AP7115-18SEG-7 offers proven field reliability but higher dropout and lower PSRR; versus MCP1700T-1802E/TT, it delivers superior noise performance and thermal robustness at the cost of higher IQ - critical for noise-sensitive analog or RF subsystems.

Availability

AP7115-18SEG-7 is available at Aetrix Electronics and suitable for wireless communication modules, GSM/GPRS handsets, and battery-powered IoT sensors requiring stable component supply across long-lifecycle industrial and consumer programs.

Supply support for AP7115-18SEG-7 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 power management, signal integrity, and protection solutions for high-volume electronics markets.

The AP7115 belongs to Diodes' low-quiescent-current LDO family, engineered specifically for space-constrained, battery-operated portable devices demanding high accuracy, low noise, and robust fault protection.

FAQ

What is the maximum allowable input voltage for AP7115-18SEG-7?

The absolute maximum input voltage is 5.5V. Operation above this level risks permanent damage to the internal PMOS pass transistor and bandgap reference circuit. Recommended operating range is 2.5V to 5.5V, with dropout performance degrading above 5.0V due to increased power dissipation.

Can the BP pin be left floating or tied directly to GND?

No - the BP pin must be connected to a 0.1µF ceramic capacitor between BP and GND. Leaving it floating increases output voltage noise and drift; tying it directly to GND disables the bandgap bypass function and degrades output accuracy and temperature stability per datasheet specifications.

Is AP7115-18SEG-7 pin-compatible with AP7315-18SG-7?

Yes - both devices use identical SOT353 pinout (IN, GND, EN, BP, OUT) and share the same footprint, pad layout, and functional pin assignments. However, AP7315-18SG-7 requires updated startup timing validation due to faster enable response and different internal compensation.

What is the minimum recommended output capacitance and ESR for stable operation?

A minimum 1µF X5R/X7R ceramic capacitor is required. ESR must be ≤1Ω across 1mA–150mA load range, as shown in the "Cout ESR vs. Load Current" stability curve (DS31333 Rev. 12–3, p.7). Lower ESR improves transient response but may cause oscillation if below 10mΩ without series resistance.