Overview
The UC2844BNG 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 power MOSFETs.
Key Specifications
| Characteristic | Symbol | Min | Typ | Max | Unit |
|---|---|---|---|---|---|
| Bias and Driver Voltages | VCC, VC | - | - | 36 | V |
| Total Power Supply and Zener Current | ICC + IZ | - | - | 30 | mA |
| Output Current, Source or Sink | IO | - | - | 1.0 | A |
| Output Energy (Capacitive Load per Cycle) | W | - | - | 5.0 | μJ |
| Reference Output Voltage | Vref | 4.95 | 5.0 | 5.05 | V |
| Oscillator Frequency | fOSC | - | 250 kHz | - | kHz |
| Startup Threshold | Vth | 14.5 | 16 | 17 | V |
| Minimum Operating Voltage After Turn-On | VCC(min) | 9.0 | 10 | 11 | V |
| Power Supply Current (Operating) | ICC | - | 12 | 17 | mA |
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 and RoHS Compliant
Applications
The UC2844BNG is designed for various power conversion applications, including:
- Off-line converters
- DC-DC converters
- Power supplies requiring high efficiency and reliability
- Automotive and industrial power systems
Q & A
- What is the primary function of the UC2844BNG?
The UC2844BNG 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 UC2844BNG?
The oscillator frequency is guaranteed at 250 kHz.
- What is the maximum output current of the UC2844BNG?
The maximum output current is 1.0 A.
- What are the startup and minimum operating voltages for the UC2844BNG?
The startup threshold is 16 V, and the minimum operating voltage after turn-on is 9.0 V.
- Does the UC2844BNG have undervoltage lockout protection?
Yes, it has undervoltage lockout protection with hysteresis for both the power supply and reference output.
- What is the power supply current during operation?
The power supply current during operation is typically 12 mA.
- Is the UC2844BNG Pb-Free and RoHS compliant?
Yes, it is Pb-Free and RoHS compliant.
- What are the common applications of the UC2844BNG?
Common applications include off-line converters, DC-DC converters, and power supplies in automotive and industrial systems.
- How is the output deadtime adjusted in the UC2844BNG?
The output deadtime is adjustable from 50% to 70% using an internal flip-flop.
- Does the UC2844BNG have ESD protection?
Yes, it contains ESD protection and exceeds the Human Body Model and Machine Model tests.
