AP7343D-135FS4-7B

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators Overview

The AP7343D-135FS4-7B is a fixed-output low dropout regulator manufactured by Diodes Incorporated, providing a precise 1.35V output with a guaranteed maximum load current of 300mA. It operates within an input voltage range of 1.7V to 5.25V and features high power supply rejection ratio performance of 75dB at 1kHz alongside low output noise of 60µVrms from 10Hz to 100kHz. The device incorporates an enable pin for power management control and includes built-in thermal shutdown and fold-back short-circuit protection. It is housed in the compact X2-DFN1010-4 (Type B) surface-mount package.

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators Feature Summary

• Integrated enable input allows for active power switching and shutdown mode control
• Built-in auto-discharge circuit ensures rapid output voltage decay when disabled
• CMOS-based architecture delivers high accuracy with minimal quiescent current consumption
• Includes comprehensive protection mechanisms against overcurrent and overheating conditions

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators Applications

• RF power supply circuits
• Portable video devices
• Wireless communication modules
• Camera systems

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators Procurement Notes

Verify the specific ordering suffix FS4-7B corresponds to the required X2-DFN1010-4 package and tape-and-reel quantity. Confirm that the 'D' designation indicates the presence of the internal discharge resistor, as this affects shutdown behavior compared to non-discharge variants. Ensure compatibility with RoHS3 and halogen-free manufacturing standards required by your assembly process.

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators Selection Notes

Select this component when a stable 1.35V rail is needed for sensitive analog or RF sections requiring low noise. The inclusion of the discharge feature makes it suitable for battery-powered applications where minimizing standby leakage is critical. Verify that the input voltage remains sufficiently above the output to maintain regulation under all expected load and temperature conditions.

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators Part Context

This part belongs to the AP7343 family of 300mA high PSRR low-noise LDOs. The 'D' prefix specifically denotes the version with an integrated output discharge resistor, distinguishing it from standard versions without this function. The FS4 suffix identifies the X2-DFN1010-4 Type B package, which offers a small footprint for dense PCB layouts.

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators Replacement Considerations

AP7343-135FS4-7B serves as a direct functional substitute if the discharge feature is not required. For automotive-grade requirements, the AP7343Q series provides equivalent electrical characteristics with extended reliability specifications.