Overview
The L78L05CZ is a three-terminal positive voltage regulator from STMicroelectronics. It is part of the L78L series, which is designed to provide fixed voltage regulation with internal current limiting and thermal shutdown, making them highly reliable and robust. These regulators 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. They can also be used in conjunction with power pass elements to create high-current voltage regulators, offering improvements over traditional Zener diode/resistor combinations with lower quiescent current and noise.
Key Specifications
| Parameter | Test Conditions | Min. | Typ. | Max. | Unit |
|---|---|---|---|---|---|
| Output Voltage (VO) | TJ = 25 °C | 4.8 | 5 | 5.2 | V |
| Output Voltage (VO) | IO = 1 to 40 mA, VI = 10 to 20 V | 4.75 | 5.25 | 5.5 | V |
| Line Regulation (∆VO) | VI = 10.5 to 20 V, TJ = 25 °C | - | - | 150 mV | mV |
| Load Regulation (∆VO) | IO = 1 to 40 mA, TJ = 25 °C | - | - | 40 mV | mV |
| Quiescent Current (Id) | TJ = 25 °C | - | 6 mA | - | mA |
| Quiescent Current Change (∆Id) | IO = 1 to 40 mA | - | - | 0.2 mA | mA |
| Output Noise Voltage (eN) | B = 10 Hz to 100 kHz, TJ = 25 °C | - | - | 60 µV | µV |
| Supply Voltage Rejection (SVR) | VI = 9 to 20 V, f = 120 Hz, IO = 40 mA, TJ = 25 °C | - | - | 36 dB | dB |
| Dropout Voltage (Vd) | - | - | - | 1.7 V | V |
Key Features
- Output current up to 100 mA
- Fixed output voltage of 5 V
- Internal current limiting and thermal shutdown for robust operation
- No external components required
- Available in ± 4% (A) or ± 8% (C) selection
- Short-circuit protection
- Low quiescent current and noise
Applications
- Local or on-card voltage regulation
- Elimination of noise and distribution problems associated with single-point regulation
- Use with power pass elements to make high-current voltage regulators
- Replacement for Zener diode/resistor combinations
- Industrial and commercial power supply systems
Q & A
- What is the output voltage of the L78L05CZ?
The output voltage of the L78L05CZ is 5 V.
- What is the maximum output current of the L78L05CZ?
The maximum output current of the L78L05CZ is up to 100 mA.
- Does the L78L05CZ have internal protection features?
Yes, the L78L05CZ has internal current limiting and thermal shutdown protection.
- Do I need external components to use the L78L05CZ?
No, the L78L05CZ does not require any external components.
- What is the operating temperature range of the L78L05CZ?
The operating temperature range of the L78L05CZ is typically from 0 to 125 °C.
- What is the dropout voltage of the L78L05CZ?
The dropout voltage of the L78L05CZ is approximately 1.7 V.
- Can the L78L05CZ be used in high-current applications?
Yes, the L78L05CZ can be used with power pass elements to create high-current voltage regulators.
- What are the typical applications of the L78L05CZ?
The L78L05CZ is typically used in local or on-card regulation, noise elimination, and as a replacement for Zener diode/resistor combinations.
- What is the quiescent current of the L78L05CZ?
The quiescent current of the L78L05CZ is approximately 6 mA at 25 °C.
- How does the L78L05CZ handle supply voltage rejection?
The L78L05CZ has a supply voltage rejection (SVR) of around 36 dB at 120 Hz.
