AP7343D-34FS4-7B

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

The AP7343D-34FS4-7B is a fixed-output low dropout regulator manufactured by Diodes Incorporated, providing a nominal output voltage of 3.4V with a guaranteed maximum output 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 control, built-in short-circuit protection, and thermal shutdown capabilities. It is housed in an X2-DFN1010-4 (Type B) package designed for dense PCB layouts.

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

• Integrated enable input allows precise power management by switching the regulator on or off via logic level signals.
• Built-in auto-discharge circuit ensures rapid output voltage decay when the device is disabled.
• CMOS-based architecture delivers high ripple rejection and low quiescent current for efficient operation.
• Includes comprehensive protection mechanisms such as fold-back short-circuit current limiting and thermal shutdown.

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

• RF power supplies
• Portable media players
• Wireless communication modules

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

Verify that the specific part number matches the required 3.4V fixed output voltage and the X2-DFN1010-4 package type. Confirm the presence of the 'D' suffix indicates the integrated discharge feature if rapid shutdown is necessary for the design. Ensure compatibility with the specified operating temperature range and input voltage constraints before finalizing procurement.

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

Select this component when a stable 3.4V rail is required from a variable input source between 1.7V and 5.25V. The choice is driven by the need for low noise performance in sensitive analog circuits and the requirement for a compact surface-mount footprint. Consider the thermal resistance characteristics of the X2-DFN1010-4 package relative to the expected load current and ambient conditions.

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

This device belongs to the AP7343 series of low dropout regulators from Diodes Incorporated. The series is characterized by high PSRR and low noise, targeting portable electronics. The AP7343D variant specifically includes an output discharge resistor, distinguishing it from non-discharge versions. It shares the same core electrical specifications and pinout with other members of the family, differing primarily in output voltage and discharge functionality.

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

AP7343-34FS4-7B

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

What is the function of the 'D' suffix in the part number?

The 'D' suffix indicates that the regulator includes an internal auto-discharge resistor connected to the output, which rapidly pulls the output voltage down when the enable pin is set to a low state.

How does the enable pin operate?

The enable pin controls the state of the regulator; driving it high turns the regulator on, while pulling it low activates the shutdown mode and engages the discharge function if present.