Overview
The UC3842BDR2G, produced by onsemi, is a high-performance fixed frequency current mode controller. It is specifically designed for off-line and DC-DC converter applications, offering a cost-effective solution with minimal external components. This device is part of the UC3842B and UC3843B series, which are tailored for various voltage applications and feature a range of protective and control mechanisms.
Key Specifications
| Parameter | Min | Typ | Max | Unit |
|---|---|---|---|---|
| VCC (Bias and Driver Voltages) | - | - | 30 | V |
| Total Power Supply and Zener Current (ICC + IZ) | - | - | 30 | mA |
| Output Current, Source or Sink (IO) | - | - | 1.0 | A |
| Reference Output Voltage (Vref) | 4.95 | 5.0 | 5.05 | V |
| Oscillator Frequency | - | 250 | - | kHz |
| UVLO Startup Threshold | 16 | - | - | V |
| UVLO Shutdown Threshold | 10 | - | - | V |
| Operating Temperature Range | -40 | - | 105 | °C |
Key Features
- Trimmed Oscillator for Precise Frequency Control: The oscillator frequency is programmable using external timing components RT and CT, ensuring precise duty cycle control.
- Current Mode Operation: Supports operation up to 500 kHz, making it suitable for high-frequency applications.
- Automatic Feed Forward Compensation: Enhances stability and performance in the control loop.
- Latching PWM for Cycle-By-Cycle Current Limiting: Ensures reliable current limiting and prevents overcurrent conditions.
- Internally Trimmed Reference with Undervoltage Lockout: Features a temperature-compensated reference and undervoltage lockout with hysteresis for robust operation.
- High Current Totem Pole Output: Capable of driving power MOSFETs with high current output.
- Low Startup and Operating Current: Minimizes power consumption during startup and operation.
- Pb-Free and Halide-Free: Compliant with environmental regulations.
Applications
The UC3842BDR2G is specifically designed for off-line and DC-DC converter applications. It is suitable for:
- Switch-mode power supplies (SMPS)
- DC-DC converters
- Power factor correction (PFC) circuits
- High-frequency power conversion systems
Q & A
- What is the primary function of the UC3842BDR2G?
The UC3842BDR2G is a high-performance fixed frequency current mode controller designed for off-line and DC-DC converter applications.
- What is the typical oscillator frequency of the UC3842BDR2G?
The oscillator frequency is typically 250 kHz, but it can be programmed using external timing components RT and CT.
- What are the UVLO thresholds for the UC3842BDR2G?
The UVLO startup threshold is 16 V, and the shutdown threshold is 10 V.
- What is the maximum output current of the UC3842BDR2G?
The maximum output current is 1.0 A.
- What type of output stage does the UC3842BDR2G have?
The UC3842BDR2G features a high current totem pole output stage.
- Is the UC3842BDR2G Pb-Free and Halide-Free?
Yes, the UC3842BDR2G is Pb-Free and Halide-Free, making it compliant with environmental regulations.
- What is the operating temperature range of the UC3842BDR2G?
The operating temperature range is from -40°C to 105°C.
- How does the UC3842BDR2G handle cycle-by-cycle current limiting?
The device features latching PWM for cycle-by-cycle current limiting, ensuring reliable current limiting and preventing overcurrent conditions.
- What type of compensation does the UC3842BDR2G offer?
The UC3842BDR2G offers automatic feed forward compensation to enhance stability and performance in the control loop.
- What are some common applications of the UC3842BDR2G?
Common applications include switch-mode power supplies (SMPS), DC-DC converters, power factor correction (PFC) circuits, and high-frequency power conversion systems.
