Overview
The UC3844BVDG is a high-performance current mode PWM (Pulse Width Modulation) controller produced by onsemi. This integrated circuit is specifically designed for off-line and DC-DC converter applications, offering a cost-effective solution with minimal external components. It features an oscillator, a temperature-compensated reference, a high-gain error amplifier, a current sensing comparator, and a high-current totem pole output, making it ideal for driving power MOSFETs.
Key Specifications
| Parameter | Min | Typ | Max | Unit |
|---|---|---|---|---|
| Minimum Operating Supply Voltage | 10.2 | - | - | V |
| Maximum Operating Supply Voltage | - | - | 30 | V |
| Switching Frequency | - | 52 | - | kHz |
| Maximum Duty Cycle | - | - | 50 | % |
| Output Current (Sink) | - | - | 1.0 | A |
| Output Voltage Swing High State | - | - | 6.2 | V |
| Output Voltage Swing Low State | - | - | 0.8 | V |
| Minimum Operating Temperature | -40 | - | - | °C |
| Maximum Operating Temperature | - | - | 105 | °C |
| Package Type | - | - | SOIC-8 | - |
Key Features
- Fixed Frequency Operation: The UC3844BVDG operates at a fixed frequency, which can be programmed using external timing components.
- Current Sensing and Limiting: It includes a current sensing comparator for cycle-by-cycle current limiting and overcurrent protection.
- Temperature-Compensated Reference: The device features a temperature-compensated reference voltage for stable operation over a wide temperature range.
- High-Gain Error Amplifier: A high-gain error amplifier is included for precise voltage regulation.
- Soft-Start and Frequency Control: The IC supports soft-start and frequency control features to ensure smooth startup and stable operation.
- Overvoltage and Undervoltage Protection: Protective features include input and reference undervoltage lockouts with hysteresis.
- Latchable Shutdown Mode: The device has a latchable shutdown mode for safety assurance.
Applications
The UC3844BVDG is optimized for various power management applications, including:
- Off-Line and DC-DC Converters: It is specifically designed for off-line and DC-DC converter applications, offering a cost-effective solution with minimal external components.
- Switch-Mode Power Supplies (SMPS): Ideal for use in SMPS due to its high performance and protective features.
- Battery Chargers and LED Drivers: Suitable for battery charging and LED driving applications where precise voltage regulation and protection are necessary.
Q & A
- Q: What is the primary function of the UC3844BVDG?
A: The UC3844BVDG is a current mode PWM controller designed for efficient power management in off-line and DC-DC converter applications.
- Q: What is the typical switching frequency of the UC3844BVDG?
A: The typical switching frequency of the UC3844BVDG is 52 kHz.
- Q: What are the key protective features of the UC3844BVDG?
A: The key protective features include input and reference undervoltage lockouts with hysteresis, cycle-by-cycle current limiting, and overvoltage protection.
- Q: What is the maximum output current of the UC3844BVDG?
A: The maximum output current of the UC3844BVDG is 1.0 A.
- Q: What package type is the UC3844BVDG available in?
A: The UC3844BVDG is available in an SOIC-8 package type.
- Q: Is the UC3844BVDG RoHS compliant?
A: Yes, the UC3844BVDG is RoHS compliant.
- Q: What is the operating temperature range of the UC3844BVDG?
A: The operating temperature range of the UC3844BVDG is from -40°C to 105°C.
- Q: Can the UC3844BVDG be used in battery charging applications?
A: Yes, the UC3844BVDG is suitable for battery charging applications due to its precise voltage regulation and protective features.
- Q: How does the soft-start feature work in the UC3844BVDG?
A: The soft-start feature in the UC3844BVDG ensures a smooth startup by gradually increasing the output voltage, preventing inrush currents and reducing stress on the system.
- Q: Are there any equivalent products to the UC3844BVDG?
A: Yes, equivalent products include the UC3844AN, UC3844ADR2G, and UC3844A, which are part of the same family and have similar features and specifications.
