AS1358-BTTT-45

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

The AS1358-BTTT-45 is a low-dropout linear regulator from the AS1358/AS1359 series, manufactured by ams OSRAM. It delivers a fixed 4.5V output with a maximum continuous load current of 150mA. The device operates within an input voltage range of 2V to 5.5V and features an ultra-low noise profile of 9µVRMS (100Hz to 100kHz). Key electrical parameters include a quiescent current of 40µA, a power-supply rejection ratio exceeding 80dB up to 10kHz, and a dropout voltage of 70mV to 95mV at 150mA for outputs ≥3V. It incorporates integrated P-channel MOSFET pass transistors, overcurrent protection, thermal shutdown, and a dedicated bypass pin for noise reduction.

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

• Ultra-low output noise achieved through advanced architecture and external bypass capacitor support
• High power-supply rejection ratio ensuring stable performance against input ripple
• Integrated P-channel MOSFET pass transistor enabling extremely low quiescent current consumption
• Built-in overcurrent limiting and thermal protection circuits for fault condition safety

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

• Mobile phones and wireless communication devices
• Personal Digital Assistants (PDAs) and handheld computers
• Bluetooth portable radios and accessories
• Digital cameras and personal audio devices

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

Verify the specific ordering code AS1358-BTTT-45 against the manufacturer's official documentation to confirm the 4.5V preset output and 150mA current rating. Ensure compatibility with the TSOT23 5-pin package dimensions and lead finish specifications. Confirm that the application environment remains within the specified operating temperature range of -40°C to +85°C. Check for any recent product change notices or end-of-life announcements directly from ams OSRAM before finalizing procurement plans.

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

Select this component when a fixed 4.5V rail is required with minimal noise impact on sensitive analog or RF sections. The 150mA current limit suits moderate-load portable applications where battery life is critical due to the low quiescent current. Verify that the input voltage stays within the 2V to 5.5V range and that the load does not exceed the guaranteed 150mA continuous output. Consider the thermal resistance of the PCB layout if operating near maximum current limits to ensure junction temperatures remain safe.

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

This part belongs to the AS1358/AS1359 family of ultra-low-noise LDOs designed for space-constrained mobile electronics. The AS1358 variant specifically provides 150mA output capability, distinguishing it from the higher-current AS1359. These regulators utilize a P-channel MOSFET pass element to minimize ground current draw, making them suitable for battery-powered systems requiring efficient power management in compact TSOT23 packages.

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

Direct functional substitutes within the same series include other AS1358 variants with different preset voltages (e.g., AS1358-BTTT-33 for 3.3V). Cross-referencing tools may identify compatible parts from other manufacturers, but verification of pinout, electrical characteristics, and package dimensions is essential. No alternative part numbers are explicitly confirmed as direct replacements in the provided datasheet.