Overview
The UC3843BD1G is a high-performance fixed frequency Current Mode Controller designed specifically for OFF-line and DC-DC converter applications. This integrated circuit from ON Semiconductor 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 power MOSFETs. The controller includes protective features such as input and reference under-voltage lockouts with hysteresis, cycle-by-cycle current limiting, programmable output dead-time, and a latch for single pulse metering. It is available in an 8-pin SOIC package and is known for its low start-up and operating current.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Supply Voltage Range | 12V - 25V | V |
| Oscillator Frequency | Up to 500 kHz | kHz |
| Output Voltage | 13.4V / 200mA | V / mA |
| Package Type | SOIC-8 | - |
| Operating Temperature Range | 0°C to 70°C | °C |
| Maximum Output Current | ±1.0 A | A |
| Under-Voltage Lockout (UVLO) Thresholds | 15 V (on), 10 V (off) | V |
| Power Dissipation at TA = 25°C | 751 mW (SOIC-8 package) | mW |
Key Features
- Trimmed oscillator for precise frequency control
- Automatic feed forward compensation
- Latching PWM for cycle-by-cycle current limiting
- Internally trimmed reference with under-voltage lockout
- High current totem pole output
- Under-voltage lockout with hysteresis
- Low start-up and operating current
- Programmable output dead-time and a latch for single pulse metering
- Separate power and ground pins for the totem pole output stage in SOIC-14 package (though UC3843BD1G is in SOIC-8)
Applications
The UC3843BD1G is suitable for various applications, including:
- Industrial power supplies
- OFF-line and DC-DC converters
- Signal processing
- Boost and flyback converters
Q & A
- What is the primary function of the UC3843BD1G?
The UC3843BD1G is a high-performance fixed frequency Current Mode Controller designed for OFF-line and DC-DC converter applications.
- What is the supply voltage range for the UC3843BD1G?
The supply voltage range is 12V to 25V.
- What is the maximum oscillator frequency of the UC3843BD1G?
The oscillator frequency can be programmed up to 500 kHz.
- What type of package is the UC3843BD1G available in?
The UC3843BD1G is available in an 8-pin SOIC package.
- What are the key protective features of the UC3843BD1G?
The key protective features include input and reference under-voltage lockouts with hysteresis, cycle-by-cycle current limiting, and programmable output dead-time.
- What is the maximum output current of the UC3843BD1G?
The maximum output current is ±1.0 A.
- What are the typical applications of the UC3843BD1G?
Typical applications include industrial power supplies, OFF-line and DC-DC converters, and signal processing.
- How does the UC3843BD1G handle under-voltage conditions?
The UC3843BD1G features under-voltage lockout with hysteresis and keeps the output in a sinking mode during undervoltage lockout.
- What is the operating temperature range of the UC3843BD1G?
The operating temperature range is 0°C to 70°C.
- Is the UC3843BD1G Pb-free and halide-free?
