Overview
The LD1085DT15R is a low drop positive voltage regulator produced by STMicroelectronics. This component is designed to provide up to 3 A of output current and is available in various fixed output voltage configurations, including 1.8 V, 2.5 V, 3.3 V, and 5 V. The LD1085 series is known for its high performance, including a typical dropout voltage of 1.3 V at 3 A, and a tight output voltage tolerance of ±1% at 25 °C and ±2% over the full temperature range. The regulator is pin-to-pin compatible with older 3-terminal adjustable regulators but offers improved performance in terms of dropout and output tolerance.
Key Specifications
| Parameter | Min. | Typ. | Max. | Unit |
|---|---|---|---|---|
| Output Voltage (VO) | 4.9 | 5 | 5.1 | V |
| Output Current (IO) | 0 | - | 3 | A |
| Dropout Voltage (Vd) | 1.3 | - | 1.5 | V |
| Quiescent Current (Iq) | 5 | - | 10 | mA |
| Line Regulation | 0.5 | - | 10 | mV |
| Load Regulation | 5 | - | 10 | mV |
| Operating Temperature Range | -40 | - | 125 | °C |
| Thermal Resistance Junction-Case (RthJC) | 3 | - | - | °C/W |
| Thermal Resistance Junction-Ambient (RthJA) | 50 | - | - | °C/W |
| Package | TO-220, TO-220FP, D²PAK, D²PAK/A | - | - | - |
Key Features
- Guaranteed output current up to 3 A
- Tight output voltage tolerance: ±1% at 25 °C and ±2% in full temperature range
- Low dropout voltage: 1.3 V at 3 A
- Internal power and thermal limiting
- Wide operating temperature range: -40 °C to 125 °C
- Pin-to-pin compatibility with standard adjustable voltage regulators
- High efficiency due to quiescent current flowing into the load
- Minimum 10 µF capacitor required for stability
- Supply voltage rejection: 60 dB at 120 Hz
- Low RMS output noise voltage: 0.003% of VO
Applications
The LD1085DT15R is suitable for a variety of applications requiring a stable and efficient voltage regulation. These include:
- Power supplies for industrial and consumer electronics
- Automotive systems requiring robust voltage regulation
- Telecommunication equipment
- Medical devices
- Any system needing a high-current, low-dropout voltage regulator
Q & A
- What is the maximum output current of the LD1085DT15R?
The LD1085DT15R can provide up to 3 A of output current. - What are the available output voltage configurations for the LD1085 series?
The LD1085 series is available in fixed output voltage configurations of 1.8 V, 2.5 V, 3.3 V, and 5 V. - What is the typical dropout voltage of the LD1085DT15R at 3 A?
The typical dropout voltage is 1.3 V at 3 A. - What is the output voltage tolerance of the LD1085DT15R?
The output voltage tolerance is ±1% at 25 °C and ±2% over the full temperature range. - What is the operating temperature range of the LD1085DT15R?
The operating temperature range is -40 °C to 125 °C. - What packages are available for the LD1085DT15R?
The LD1085DT15R is available in TO-220, TO-220FP, D²PAK, and D²PAK/A packages. - What is the thermal resistance junction-case (RthJC) for the TO-220 package?
The thermal resistance junction-case (RthJC) for the TO-220 package is 3 °C/W. - What is the minimum capacitor required for stability?
A minimum 10 µF capacitor is required for stability. - How efficient is the LD1085DT15R in terms of quiescent current?
The quiescent current flows into the load, increasing efficiency. - What is the supply voltage rejection of the LD1085DT15R?
The supply voltage rejection is 60 dB at 120 Hz.
