AP7343D-185FS4-7B

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

The AP7343D-185FS4-7B is a fixed-output low dropout regulator manufactured by Diodes Incorporated, providing a stable 1.85V output with a maximum current of 300mA. It operates within an input voltage range of 1.7V to 5.25V and features high power supply rejection ratio (PSRR) of 75dB at 1kHz. The device incorporates an enable pin for power control, thermal shutdown protection, and short-circuit current limiting. Packaged in the compact X2-DFN1010-4 (Type B) format, it supports dense PCB layouts and functions reliably across an ambient temperature range of -40°C to +85°C.

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

• Integrated enable pin allows precise power management and shutdown control
• Built-in discharge circuit ensures rapid output voltage decay when disabled
• CMOS process technology delivers low quiescent current and low output noise
• Includes comprehensive protection against overcurrent and thermal overload

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

• RF power supplies
• Portable media players
• Wireless communication devices
• Smartphones and tablets

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

Verify that the ordering suffix FS4 corresponds to the X2-DFN1010-4 package type and 7B indicates tape and reel packaging. Confirm the 'D' designation confirms the presence of the auto-discharge feature on the output node. Ensure compatibility with RoHS3 and halogen-free manufacturing standards required for your assembly environment.

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

Select this component when a fixed 1.85V rail is required with minimal footprint constraints. The inclusion of the discharge feature distinguishes it from non-discharge variants, making it suitable for applications requiring fast output settling times during power cycles. Evaluate thermal resistance requirements based on the specific PCB copper area available for heat dissipation.

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

This part belongs to the AP7343 family of 300mA LDOs designed for low-power handheld equipment. The series offers various fixed output voltages ranging from 0.9V to 3.6V. The 'D' suffix specifically denotes versions equipped with an internal N-channel auto-discharge resistor, differentiating them from standard AP7343 parts which lack this function.

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

AP7343-185FS4-7B

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 integrated N-channel auto-discharge resistor, which actively pulls the output voltage down when the enable pin is low.

How does the enable pin operate?

Driving the EN pin high turns the regulator on, while pulling it low activates shutdown mode and engages the output discharge circuit.