Overview
The LD2985BM18R is a 150 mA fixed output voltage regulator produced by STMicroelectronics. It is characterized by its ultra-low dropout voltage and low quiescent current, making it particularly suitable for low noise, low power applications, and battery-powered systems. The device features a logic-controlled electronic shutdown function and an internal current and thermal limit, ensuring reliable operation. The LD2985BM18R is available in a small SOT23-5L package and operates over a temperature range of -40°C to 125°C.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Output Voltage (nom) | 1.8 | V |
| Output Current (nom) | 0.15 | A |
| Dropout Voltage | 280 mV at 150 mA, 7 mV at 1 mA | mV |
| Quiescent Current | 2 mA typ. at 150 mA load, 80 µA at no load | mA/µA |
| Operating Temperature Range | -40 to 125 | °C |
| Package | SOT23-5L | |
| Output Noise Voltage | 30 µVrms | µVrms |
| Short Circuit Current | 400 mA | mA |
| Line Regulation | 0.003 to 0.014 %/V | %/V |
Key Features
- Very low dropout voltage (280 mV at 150 mA and 7 mV at 1 mA load)
- Very low quiescent current (2 mA typ. at 150 mA load and 80 µA at no load)
- Output current up to 150 mA
- Logic controlled electronic shutdown
- Internal current and thermal limit
- Low output noise voltage (30 µVrms)
- Small package (SOT23-5L)
- Temperature range: -40°C to 125°C
- External capacitor (CBYP=10 nF) for noise reduction
Applications
The LD2985BM18R is typically used in various low power and low noise applications, including:
- Cellular phones
- Palmtop laptop computers
- Personal digital assistants (PDAs)
- Personal stereos
- Camcorders and cameras
Q & A
- What is the output voltage of the LD2985BM18R?
The output voltage of the LD2985BM18R is 1.8 V.
- What is the maximum output current of the LD2985BM18R?
The maximum output current is 150 mA.
- What is the dropout voltage of the LD2985BM18R?
The dropout voltage is 280 mV at 150 mA and 7 mV at 1 mA load.
- How does the shutdown function work on the LD2985BM18R?
The shutdown function is controlled by the INHIBIT pin, which is TTL compatible. When the INHIBIT pin is pulled low, the device enters sleep mode with a quiescent current of less than 1 µA.
- What is the operating temperature range of the LD2985BM18R?
The operating temperature range is -40°C to 125°C.
- How can the noise be reduced in the LD2985BM18R?
Noise can be reduced by connecting an external capacitor (CBYP=10 nF) between the bypass pin and GND, which reduces the noise to 30 µVrms.
- What package type is the LD2985BM18R available in?
The LD2985BM18R is available in a SOT23-5L package.
- What are some typical applications of the LD2985BM18R?
Typical applications include cellular phones, palmtop laptop computers, personal digital assistants (PDAs), personal stereos, camcorders, and cameras.
- What is the short circuit current limit of the LD2985BM18R?
The short circuit current is internally limited to 400 mA.
- What is the line regulation of the LD2985BM18R?
The line regulation is 0.003 to 0.014 %/V.
