Skip to product information
1 of 1
Image shown is a representation only. Exact specifications should be obtained from the product data sheet.
Regular price $1.28
Regular price $0.32 Sale price $1.28
Sale Sold out
Quantity Unit Price Total Price
1 $1.28 $1.28
15+ $0.29 $4.35
25+ $0.29 $7.25
50+ $0.27 $13.50
100+ $0.24 $24.00
N+ $0.05 Price Inquiry
Shipping calculated at checkout.
Quantity
Component Recycling

Request Quote / Inquiry

Product attributes Property Value
Manufacturer Union Semiconductor International Limited
Product Series UM1540
Packaging Tape & Reel (TR) |
Output Configuration Positive
Output Type Fixed
Number of Regulators 1
Voltage - Input (Max) 6V
Voltage - Output (Min/Fixed) 2.8V
Voltage - Output (Max) -
Voltage Dropout (Max) 0.33V @ 200mA
Current - Output 300mA
Current - Quiescent (Iq) 1.5 µA
Current - Supply (Max) -
PSRR 56dB ~ 42dB (100Hz ~ 1kHz)
Control Features Enable
Protection Features Over Current, Over Temperature
Operating Temperature -40°C ~ 125°C (TJ)
Grade -
Qualification -
Mounting Type Surface Mount
Package / Case 4-XDFN Exposed Pad
Supplier Device Package 4-DFN (1x1)
ROHS RoHS Compliant - Hazardous Substance Free Electronic Components | HQICKEY

The UM1540DB-28 is an ultra-low quiescent current LDO regulator providing a fixed 2.8V output with 300mA capability. Its standout feature is the 1.5 µA quiescent current, making it exceptional for battery-powered and energy-harvesting applications. The 0.33V dropout at 200mA ensures efficient operation. Packaged in a tiny 4-DFN (1x1), it fits seamlessly into space-constrained designs.

  • Ultra-Low Quiescent Current: 1.5 µA extends battery life in standby-heavy applications.
  • High Output Current: 300mA capability in a 1x1mm package.
  • Efficient Dropout: 0.33V at 200mA minimizes power loss.
  • Minimal Footprint: 4-DFN package ideal for micro-sized PCBs.

Ultra-Low-Power IoT Devices

The 1.5 µA quiescent current is ideal for battery-powered sensors that spend most of their time in sleep mode.

Energy Harvesting Systems

Minimal current draw preserves harvested energy from solar or vibration sources, maximizing system uptime.

Portable Medical Monitors

Stable 2.8V output with low dropout supports continuous operation of wearable health trackers.

Smart Home Sensors

Compact 4-DFN package and low power consumption suit wireless door/window sensors and thermostats.

RTC Backup Power

The ultra-low quiescent current makes it perfect for maintaining real-time clocks in battery-backed applications.

Q: What is the output voltage of the UM1540DB-28?
A: The fixed output voltage is 2.8V.
Q: What is the maximum output current?
A: It can deliver up to 300mA.
Q: What is the input voltage range?
A: The input voltage range is not specified in the provided data; refer to the datasheet.
Q: What is the dropout voltage?
A: The dropout voltage is 0.33V at 200mA load.
Q: What is the quiescent current?
A: The quiescent current is extremely low at 1.5 µA.
Q: What package is available?
A: It comes in a 4-DFN (1x1) package.
Base Product Number : UM1540DB-28
2.8V 300mA DFN LDO Linear Regulator Ultra-Low Quiescent Union Semiconductor
Q: What is the output voltage of the UM1540DB-28?
A: The fixed output voltage is 2.8V.
Q: What is the maximum output current?
A: It can deliver up to 300mA.
Q: What is the input voltage range?
A: The input voltage range is not specified in the provided data; refer to the datasheet.
Q: What is the dropout voltage?
A: The dropout voltage is 0.33V at 200mA load.
Q: What is the quiescent current?
A: The quiescent current is extremely low at 1.5 µA.
Q: What package is available?
A: It comes in a 4-DFN (1x1) package.