Diodes Incorporated AP1118S90L-13

Overview

AP1118S90L-13 from Anachip Corp. is a 1A positive low dropout fixed-output linear regulator with 9.0V output, TTL/CMOS-compatible enable function, <1.4V dropout at full load, and SOP-8L lead-free package. It delivers stable voltage for low-current 3.3V/5V logic supplies and high-speed bus termination in space-constrained PCBs.

For engineers reviewing the AP1118S90L-13 datasheet, AP1118S90L-13 pinout, AP1118S90L-13 application, or AP1118S90L-13 equivalent, key selection criteria include dropout voltage under 1A load, thermal shutdown behavior, EN pin logic polarity, output voltage tolerance at temperature extremes, and SOIC-8 thermal resistance (θ_JA = 150°C/W).

Technical Context

The AP1118S90L-13 integrates a PNP pass transistor with internal current limiting and thermal shutdown circuitry, operating as a fixed-output LDO without external feedback components. Its enable input features an internal ~100kΩ pull-down resistor, requiring logic-low or open condition to activate regulation.

Designed for input voltages up to 18V, it maintains regulation when V_IN ≥ V_OUT + 1.3V and guarantees ≤1.4V dropout across 0–1A load at T_J = 25°C. Ripple rejection is 60–70dB at 120Hz with 25µF tantalum output capacitance.

Key Specifications

Pinout & Package

SOP-8L surface-mount package with exposed thermal pad (pin 5 connected to V_OUT tab); 5.05 mm × 3.90 mm footprint, 1.60 mm height, lead-free finish per RoHS.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MIC29302WU-9.0 and LD1086V90, AP1118S90L-13 offers enable control and SOP-8L compactness at 1A rating, making it optimal for space-limited digital logic supplies where sequencing and thermal management are constrained.

Availability

AP1118S90L-13 is available at Aetrix Electronics and suitable for PC peripheral power, communication module bias, VGA card core supply, and legacy industrial controller designs requiring stable component supply and long-term obsolescence support.

Supply support for AP1118S90L-13 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

Anachip Corp. is a Taiwan-based semiconductor company specializing in analog and power management ICs, founded in 1996 and focused on cost-effective, high-reliability solutions for consumer and industrial markets.

The AP1118 product line delivers low-dropout linear regulators optimized for low-voltage logic supply and bus termination, targeting applications where simplicity, small footprint, and enable-controlled sequencing are essential.

FAQ

What is the minimum input voltage required for AP1118S90L-13 to regulate at 9.0V output?

The device requires V_IN ≥ V_OUT + 1.3V to maintain regulation, so minimum valid input is 10.3V. At 1A load, dropout rises to 1.4V, meaning 10.4V is the practical minimum to ensure margin across temperature and process variation. Operation below this threshold results in unregulated output tracking input minus dropout.

Can AP1118S90L-13 be used without an external output capacitor?

No - a minimum 10µF capacitor must be placed between V_OUT and GND to ensure loop stability, as specified in the datasheet. Omitting it risks oscillation or excessive output ripple. For best transient response, 100µF tantalum or low-ESR ceramic is recommended, especially under 1A dynamic loads.

How does the enable pin behave when left floating?

Pin 3 (EN) has an internal ~100kΩ pull-down resistor, so a floating EN defaults to logic-low and enables regulation. However, in noisy environments, floating may cause unintended toggling; best practice is to tie EN to GND via a 10kΩ resistor or actively drive it to avoid false disable events.

Is AP1118S90L-13 suitable for powering analog sensors requiring ultra-low noise?

While its 60–70dB ripple rejection helps suppress low-frequency switching noise, AP1118S90L-13 lacks dedicated noise-reduction features like bypass capacitors or ultra-low PSRR above 10kHz. For precision analog sensors, consider adding a second-stage RC filter or using a specialized low-noise LDO - this part is optimized for digital logic supply, not sub-mV analog references.