Overview
The L78L33ABUTR is a three-terminal positive voltage regulator from STMicroelectronics, part of the L78L series. These regulators are designed to be highly reliable and robust, featuring internal current limiting and thermal shutdown, making them essentially indestructible. They are suitable for a wide range of applications, including local or on-card regulation to eliminate noise and distribution problems associated with single-point regulation. The L78L33ABUTR can deliver up to 100 mA output current with adequate heat-sinking.
Key Specifications
| Parameter | Test Conditions | Min. | Typ. | Max. | Unit |
|---|---|---|---|---|---|
| Output Voltage (VO) | TJ = 25 °C | 3.168 | 3.3 | 3.432 | V |
| Output Voltage (VO) | IO = 1 to 40 mA, VI = 5.3 to 20 V | 3.135 | 3.3 | 3.465 | V |
| Line Regulation (∆VO) | VI = 5.4 to 20 V, TJ = 25 °C | - | - | 150 mV | mV |
| Load Regulation (∆VO) | IO = 1 to 100 mA, TJ = 25 °C | - | - | 60 mV | mV |
| Quiescent Current (Id) | TJ = 25 °C | - | 6 | - | mA |
| Quiescent Current Change (∆Id) | IO = 1 to 40 mA | - | - | 0.1 mA | mA |
| Output Noise Voltage (eN) | B = 10 Hz to 100 kHz, TJ = 25 °C | - | - | 40 µV | µV |
| Supply Voltage Rejection (SVR) | VI = 6.3 to 16.3 V, f = 120 Hz, IO = 40 mA, TJ = 25 °C | - | - | 41 dB | dB |
| Dropout Voltage (Vd) | - | - | - | 2 V | V |
| Operating Temperature (TJ) | - | -40 | - | 125 | °C |
Key Features
- Output current up to 100 mA
- Fixed output voltage of 3.3 V
- Internal current limiting and thermal shutdown for robust operation
- Short-circuit protection
- No external components required
- Available in ± 4% (A) or ± 8% (C) selection
- Low quiescent current and low noise
Applications
- Local or on-card regulation to eliminate noise and distribution problems
- Replacement for Zener diode/resistor combinations
- Use with power pass elements to make high-current voltage regulators
- Industrial applications requiring stable and reliable voltage regulation
Q & A
- What is the maximum output current of the L78L33ABUTR?
The maximum output current is up to 100 mA.
- What is the fixed output voltage of the L78L33ABUTR?
The fixed output voltage is 3.3 V.
- Does the L78L33ABUTR require external components for operation?
No, it does not require any external components.
- What are the key protection features of the L78L33ABUTR?
The key protection features include internal current limiting and thermal shutdown, as well as short-circuit protection.
- What is the operating temperature range of the L78L33ABUTR?
The operating temperature range is from -40 °C to 125 °C.
- What is the quiescent current of the L78L33ABUTR at 25 °C?
The quiescent current at 25 °C is 6 mA.
- What is the dropout voltage of the L78L33ABUTR?
The dropout voltage is 2 V.
- Can the L78L33ABUTR be used in high-current applications?
Yes, it can be used with power pass elements to make high-current voltage regulators.
- What are the typical applications of the L78L33ABUTR?
Typical applications include local or on-card regulation, replacement for Zener diode/resistor combinations, and industrial applications requiring stable and reliable voltage regulation.
- What is the supply voltage rejection of the L78L33ABUTR?
The supply voltage rejection is 41 dB at VI = 6.3 to 16.3 V, f = 120 Hz, IO = 40 mA, and TJ = 25 °C.
