Diodes Incorporated AP1117YG-13

Overview

AP1117YG-13 from Diodes Incorporated is a 1A low-dropout linear regulator in SOT89-3 package, fixed 3.3V output, with ≤1.4V dropout at full load, 6.4–18V input range, and guaranteed operation from 0°C to +125°C junction temperature - designed for stable 3.3V logic supply in PC peripherals and communication interfaces.

For engineers reviewing the AP1117YG-13 datasheet, AP1117YG-13 pinout, AP1117YG-13 application, or AP1117YG-13 equivalent, this page delivers verified pin functions, thermal resistance values (θJA = 164°C/W), load regulation (±33 mV), ripple rejection (70 dB), and real-world decoupling guidance for MLCC stability.

Technical Context

The AP1117YG-13 implements an internal bandgap reference (1.25 V), error amplifier, and NPN pass transistor in a fixed-output configuration - no external feedback resistors required. Its dropout voltage remains ≤1.4 V across 0–1 A load and full temperature range, enabling regulation from 6.4 V input down to 3.3 V output.

Thermal shutdown activates at ~150°C junction temperature, and current limiting protects against short-circuit conditions. The device requires ≥4.7 µF ceramic (X7R) or tantalum output capacitor with ESR ≤0.5 Ω, and supports stable operation with MLCCs - unlike legacy '1117 regulators limited to high-ESR electrolytics.

Key Specifications

Pinout & Package

SOT89-3 package: 3-pin surface-mount, thermally enhanced plastic case with exposed tab connected to VOUT for PCB heat spreading. Pin 1 = Adj (GND), Pin 2 = VOUT, Pin 3 = VIN. Tab is electrically tied to VOUT - must be routed to ground plane only via thermal vias if heat sinking is required.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AMS1117-3.3 and LD1117S33TR, AP1117YG-13 offers superior thermal robustness (125°C TJ rating), guaranteed MLCC compatibility, and halogen-free construction - making it optimal for compact, high-reliability consumer and industrial designs where footprint and regulatory compliance are critical.

Availability

AP1117YG-13 is available at Aetrix Electronics and suitable for PC peripheral power, communication interface supply, VGA card logic, and consumer equipment I/O rails requiring stable component supply, long-term lifecycle support, and RoHS/halogen-free compliance.

Supply support for AP1117YG-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

Diodes Incorporated is a global semiconductor company specializing in discrete, analog, and mixed-signal devices, with design and manufacturing operations across Asia and the Americas.

The AP1117 series belongs to Diodes' precision linear regulator product line, engineered for high-current, low-noise, thermally robust local regulation in computing, communications, and consumer electronics - emphasizing dropout performance, MLCC compatibility, and extended temperature reliability.

FAQ

What is the minimum input voltage required for AP1117YG-13 to regulate 3.3 V at 1 A?

The AP1117YG-13 requires VIN ≥ VOUT + dropout voltage. With a maximum dropout of 1.4 V at 1 A, the minimum valid input is 4.7 V. However, the datasheet specifies 4.8 V as the lower limit for 3.3 V operation to ensure margin across temperature and process variation - below this, regulation cannot be guaranteed.

Can AP1117YG-13 be used with a 22 µF X7R ceramic capacitor instead of tantalum?

Yes - the AP1117YG-13 is explicitly characterized and guaranteed stable with ≥4.7 µF X7R MLCCs (ESR ≤0.5 Ω). A 22 µF X7R capacitor improves transient response and reduces board area versus tantalum, and is recommended for sub-zero operation per Note 11 in the datasheet.

Is the thermal tab of the SOT89-3 package electrically connected, and how should it be handled on the PCB?

Yes - the exposed tab on the AP1117YG-13 SOT89-3 is internally connected to VOUT. It must not be shorted to ground or other nets. For thermal performance, connect it to a dedicated 3.3 V copper pour using ≥4 thermal vias (0.3 mm diameter) to inner ground planes - never float or isolate the tab.

Does AP1117YG-13 include reverse-polarity protection?

No - the AP1117YG-13 lacks integrated reverse-voltage protection. If input polarity reversal is possible in the system, an external series Schottky diode (e.g., 1N5819) or PMOS-based protection circuit must be added - otherwise, reverse bias can damage the internal pass transistor and bandgap reference.