Overview
The LM1085ISX-3.3 from Texas Instruments is a low dropout positive voltage regulator, part of the LM1085 series. This regulator is designed to provide a maximum output current of 3A with a fixed output voltage of 3.3V. It features a maximum dropout voltage of 1.5V at 3A of load current, making it suitable for high-efficiency linear regulation applications. The LM1085ISX-3.3 has the same pin-out as the industry-standard LM317 and includes current limiting and thermal shutdown protection for enhanced reliability.
Key Specifications
| Parameter | Min | Typical | Max | Units |
|---|---|---|---|---|
| Output Voltage | - | 3.3 | - | V |
| Maximum Output Current | - | - | 3 | A |
| Voltage Dropout (Max) | - | - | 1.5 @ 3A | V |
| Line Regulation | - | 0.015% | - | % |
| Load Regulation | - | 0.1% | - | % |
| Quiescent Current | 5.0 | - | 10.0 | mA |
| Operating Temperature | -40 | - | 125 | °C |
| Ripple Rejection (PSRR) | 60 | - | 72 | dB @ 120Hz |
| Input Voltage (Max) | - | - | 27 | V |
| Package | - | - | TO-263-4, D2Pak (3 Leads + Tab), TO-263AA | - |
Key Features
- Available in fixed output voltage versions (3.3V, 5.0V, 12V) and an adjustable version.
- Maximum dropout voltage of 1.5V at 3A of load current.
- Current limiting and thermal shutdown protection.
- High line and load regulation: 0.015% and 0.1% respectively.
- Ripple rejection of up to 72dB at 120Hz.
- Quiescent current of 5.0 to 10.0 mA.
- Operating temperature range from -40°C to 125°C.
- Available in TO-220 and TO-263 packages.
Applications
- High efficiency linear regulators.
- Battery chargers.
- Post regulation for switching supplies.
- Constant current regulators.
- Microprocessor power supplies.
Q & A
- What is the maximum output current of the LM1085ISX-3.3? The maximum output current is 3A.
- What is the fixed output voltage of the LM1085ISX-3.3? The fixed output voltage is 3.3V.
- What is the maximum dropout voltage of the LM1085ISX-3.3? The maximum dropout voltage is 1.5V at 3A of load current.
- Does the LM1085ISX-3.3 have built-in protection features? Yes, it includes current limiting and thermal shutdown protection.
- What is the line regulation of the LM1085ISX-3.3? The line regulation is 0.015% typical.
- What is the load regulation of the LM1085ISX-3.3? The load regulation is 0.1% typical.
- What is the ripple rejection (PSRR) of the LM1085ISX-3.3? The ripple rejection is up to 72dB at 120Hz.
- What are the available packages for the LM1085ISX-3.3? It is available in TO-263-4, D2Pak (3 Leads + Tab), and TO-263AA packages.
- What is the operating temperature range of the LM1085ISX-3.3? The operating temperature range is from -40°C to 125°C.
- What are some common applications of the LM1085ISX-3.3? Common applications include high efficiency linear regulators, battery chargers, post regulation for switching supplies, constant current regulators, and microprocessor power supplies.
