Overview
The UC3843BVD1 is a high-performance fixed frequency current mode controller from onsemi, designed for off-line and DC-DC converter applications. This integrated circuit offers a cost-effective solution with minimal external components, making it ideal for a variety of power management needs. 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 suited for driving power MOSFETs. The device also 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
| Parameter | Symbol | Min | Typ | Max | Unit |
|---|---|---|---|---|---|
| Startup Threshold (VCC) | Vth | 7.8 | 8.4 | 9.0 | V |
| Minimum Operating Voltage After Turn-On (VCC) | VCC(min) | 7.0 | 7.6 | 8.2 | V |
| Oscillator Frequency | fOSC | 49 | 52 | 56 | kHz |
| Output Current, Source or Sink | IO | 1.0 | A | ||
| Reference Output Voltage | Vref | 4.95 | 5.0 | 5.05 | V |
| Operating Junction Temperature | TJ | 150 | °C | ||
| Operating Ambient Temperature | TA | -40 | 105 | °C | |
| Package Type | SOIC-8 |
Key Features
- Trimmed oscillator for precise duty cycle control
- Temperature-compensated reference
- High gain error amplifier
- Current sensing comparator
- High current totem pole output for driving power MOSFETs
- Input and reference undervoltage lockouts with hysteresis
- Cycle-by-cycle current limiting
- Programmable output deadtime
- Latch for single pulse metering
- Low startup and operating current
- Pb-free packages available
Applications
The UC3843BVD1 is suitable for a variety of applications, including:
- Off-line power supplies
- DC-DC converters
- Flyback converters
- Other high-performance power management systems requiring precise control and protection features
Q & A
- What is the primary function of the UC3843BVD1?
The UC3843BVD1 is a high-performance fixed frequency current mode controller designed for off-line and DC-DC converter applications.
- What are the key protective features of the UC3843BVD1?
The device includes input and reference undervoltage lockouts with hysteresis, cycle-by-cycle current limiting, programmable output deadtime, and a latch for single pulse metering.
- What is the typical oscillator frequency of the UC3843BVD1?
The typical oscillator frequency is 52 kHz.
- What is the maximum output current of the UC3843BVD1?
The maximum output current is 1.0 A.
- What is the reference output voltage of the UC3843BVD1?
The reference output voltage is typically 5.0 V.
- What are the operating temperature ranges for the UC3843BVD1?
The operating junction temperature range is up to 150°C, and the operating ambient temperature range is from -40°C to 105°C.
- In what package types is the UC3843BVD1 available?
The UC3843BVD1 is available in SOIC-8 packages.
- Is the UC3843BVD1 available in Pb-free packages?
- What are some common applications for the UC3843BVD1?
- What is the startup threshold voltage for the UC3843BVD1?
