Overview
The UC3843DX, produced by ON Semiconductor, is a high-performance, fixed-frequency, current-mode PWM (Pulse Width Modulation) controller. This integrated circuit is specifically designed for off-line and DC-DC converter applications, offering a cost-effective solution with minimal external components. The UC3843DX is part of the UC3842/UC3843/UC3844/UC3845 series, known for their versatility and reliability in power supply systems.
Key Specifications
| Parameter | Symbol | Min | Typ | Max | Unit |
|---|---|---|---|---|---|
| Supply Voltage | VCC | - | - | 30 | V |
| Output Current | IO | - | - | ±1 | A |
| Reference Output Voltage | VREF | 4.90 | 5.00 | 5.10 | V |
| Line Regulation | ∆VREF | - | - | 20 | mV |
| Load Regulation | ∆VREF | - | - | 25 | mV |
| Oscillation Frequency | f | 47 | 52 | 57 | kHz |
| Operating Temperature Range | TA | 0 | - | 70 | °C |
| Storage Temperature Range | TSTG | -65 | - | 150 | °C |
Key Features
- High-Voltage Start-up Option: Capable of operating at input voltages as high as 40V.
- Integrated Under-voltage Lockout (UVLO): Ensures reliable operation by preventing the output from triggering until the voltage reaches a threshold (8.5V on, 7.9V off for UC3843DX).
- Adjustable Output Frequency: Various frequencies can be set to achieve optimal performance in varying applications, up to 500 kHz.
- Current Limit Control: Integrated circuit protects against excessive current flow with an adjustable current limit feature.
- Internal Soft-Start: Reduces inrush current and enhances system stability during initial power-up.
- Thermal Shutdown: Built-in protection against overheating to ensure long-term reliability).
- Precision Reference Voltage: Offers a stable output voltage of 5V for reference use).
- Low Start-up Current: Minimizes power consumption during the start-up phase, ideal for energy-sensitive applications).
Applications
- Switching Power Supplies: Ideal for various power supply applications requiring high efficiency and reliability).
- DC-DC Converters: Suitable for both isolated and non-isolated DC-DC converter designs).
- Power Factor Correction Circuits: Enhances power factor in AC-DC conversion systems).
- Battery Chargers: Used in battery charging systems due to its precise voltage and current control features).
- Voltage Regulation Systems: Effective in voltage regulation systems requiring stable output voltages).
- Consumer Electronics: Found in various consumer electronic devices requiring efficient power management).
- Telecommunication Equipment: Used in telecommunication equipment for reliable power supply).
- Industrial Automation Systems: Suitable for industrial automation systems requiring robust power control).
Q & A
- What is the primary function of the UC3843DX?
The UC3843DX is a fixed-frequency, current-mode PWM controller designed for off-line and DC-DC converter applications.
- What are the UVLO thresholds for the UC3843DX?
The UVLO thresholds for the UC3843DX are 8.5V (on) and 7.9V (off)).
- What is the maximum operating frequency of the UC3843DX?
The UC3843DX can operate at frequencies up to 500 kHz).
- Does the UC3843DX have an internal soft-start feature?
Yes, the UC3843DX includes an internal soft-start feature to reduce inrush current and enhance system stability during initial power-up).
- What is the maximum supply voltage for the UC3843DX?
The maximum supply voltage for the UC3843DX is 30V).
- What are the typical applications of the UC3843DX?
The UC3843DX is used in switching power supplies, DC-DC converters, power factor correction circuits, battery chargers, voltage regulation systems, consumer electronics, telecommunication equipment, and industrial automation systems).
- What is the reference output voltage of the UC3843DX?
The reference output voltage of the UC3843DX is 5.0V, with a tolerance of 4.90V to 5.10V).
- Does the UC3843DX have thermal shutdown protection?
Yes, the UC3843DX includes thermal shutdown protection to prevent overheating and ensure long-term reliability).
- What is the operating temperature range of the UC3843DX?
The operating temperature range of the UC3843DX is from 0°C to 70°C).
- What is the storage temperature range for the UC3843DX?
The storage temperature range for the UC3843DX is from -65°C to 150°C).
