Overview
The UC3843BDR2G is a high-performance fixed frequency current mode 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 a trimmed oscillator for precise duty cycle control, a temperature-compensated reference, a high-gain error amplifier, a current sensing comparator, and a high-current totem pole output ideal for driving a power MOSFET. The device includes protective features such as input and reference undervoltage lockouts with hysteresis, cycle-by-cycle current limiting, programmable output deadtime, and a latch for single pulse metering.
Key Specifications
| Specification | Value |
|---|---|
| Supply Current (Max) | 17 mA |
| Supply Voltage | 7.6 V to 30 V |
| Turn On Threshold Voltage | 16 V |
| Turn Off Threshold Voltage | 10 V |
| Duty Cycle (Max) | 96% |
| Frequency (Max) | 275 kHz |
| Operating Temperature Range | -40°C to +105°C |
| Package Style | SOIC-14 |
| Mounting Method | Surface Mount |
Key Features
- Trimmed Oscillator for Precise Frequency Control
- Oscillator Frequency Guaranteed at 250 kHz
- Current Mode Operation to 500 kHz
- Automatic Feed Forward Compensation
- Latching PWM for Cycle-By-Cycle Current Limiting
- Internally Trimmed Reference with Undervoltage Lockout
- High Current Totem Pole Output
- Undervoltage Lockout with Hysteresis
- Low Startup and Operating Current
- Pb-Free and Halide-Free Device
Applications
The UC3843BDR2G is designed for off-line and DC-DC converter applications. It is particularly suited for cost-effective solutions that require minimal external components. These applications include but are not limited to:
- Off-Line Converters
- DC-DC Converters
- Power Supply Systems
- MOSFET Driver Applications
Q & A
- What is the maximum supply voltage for the UC3843BDR2G?
The maximum supply voltage is 30 V.
- What is the operating temperature range of the UC3843BDR2G?
The operating temperature range is -40°C to +105°C.
- What is the maximum duty cycle of the UC3843BDR2G?
The maximum duty cycle is 96%.
- What type of output does the UC3843BDR2G have?
The UC3843BDR2G has a high current totem pole output.
- Does the UC3843BDR2G have undervoltage lockout protection?
Yes, it includes input and reference undervoltage lockouts with hysteresis.
- What is the maximum frequency of operation for the UC3843BDR2G?
The maximum frequency of operation is 275 kHz.
- What package styles are available for the UC3843BDR2G?
The device is available in SOIC-8 and SOIC-14 packages.
- Is the UC3843BDR2G Pb-Free and Halide-Free?
Yes, it is a Pb-Free and Halide-Free device.
- What are the protective features of the UC3843BDR2G?
The device includes cycle-by-cycle current limiting, programmable output deadtime, and a latch for single pulse metering.
- How is the oscillator frequency programmed in the UC3843BDR2G?
The oscillator frequency is programmed by the values chosen for the timing components RT and CT.
