Overview
The UC3844BVD1R2G 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 an oscillator, 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, cycle-by-cycle current limiting, and programmable output deadtimes.
Key Specifications
| Parameter | Min | Typ | Max | Unit |
|---|---|---|---|---|
| Supply Voltage (Vcc/Vdd) | 10 | - | 30 | V |
| Oscillator Frequency | - | 250 | - | kHz |
| Output Switching Frequency | - | - | 500 | kHz |
| Reference Output Voltage | 4.95 | 5.0 | 5.05 | V |
| Line Regulation | - | - | 20 | mV |
| Load Regulation | - | - | 25 | mV |
| Temperature Stability | - | - | 0.2 | mV/°C |
| Output Voltage High State | - | - | 6.2 | V |
| Output Voltage Low State | - | - | 1.1 | V |
| Current Sense Input Voltage Gain | 2.85 | 3.0 | 3.15 | V/V |
| Maximum Current Sense Input Threshold | 0.9 | 1.0 | 1.1 | V |
| Power Supply Rejection Ratio | - | - | 70 | dB |
| Operating Temperature | 0 | - | 70 | °C |
| Package Type | - | - | SOIC-8 | - |
| Mounting Type | - | - | Surface Mount | - |
Key Features
- Trimmed Oscillator for Precise Frequency Control
- Oscillator Frequency Guaranteed at 250 kHz
- Current Mode Operation to 500 kHz Output Switching Frequency
- Output Deadtime Adjustable from 50% to 70%
- 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 Packages are Available
- ESD Protection and Latch-Up Protection
Applications
The UC3844BVD1R2G is designed for various power management applications, including:
- Off-line converters
- Dc-dc converters
- Boost and flyback topologies
- Step-up and step-up/step-down configurations
Q & A
- What is the primary function of the UC3844BVD1R2G?
The UC3844BVD1R2G 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 UC3844BVD1R2G?
The oscillator frequency is guaranteed at 250 kHz.
- What is the maximum output switching frequency of the UC3844BVD1R2G?
The maximum output switching frequency is up to 500 kHz.
- What are the key protective features of the UC3844BVD1R2G?
The device includes input and reference undervoltage lockouts, cycle-by-cycle current limiting, and programmable output deadtimes.
- What is the reference output voltage of the UC3844BVD1R2G?
The reference output voltage is between 4.95 V and 5.05 V.
- What is the operating temperature range of the UC3844BVD1R2G?
The operating temperature range is from 0°C to 70°C.
- What package type is the UC3844BVD1R2G available in?
The device is available in an SOIC-8 package.
- Does the UC3844BVD1R2G have ESD protection?
Yes, the device includes ESD protection and exceeds the Human Body Model and Machine Model tests.
- What are the typical applications of the UC3844BVD1R2G?
The device is used in off-line converters, dc-dc converters, boost and flyback topologies, and step-up and step-up/step-down configurations.
- Is the UC3844BVD1R2G lead-free and RoHS compliant?
Yes, the device is lead-free and RoHS compliant.
