Overview
The UC3843AD1R2 from onsemi is a high-performance current mode PWM (Pulse Width Modulation) controller designed for off-line and DC-to-DC converter applications. Introduced on March 4, 1999, this component is part of the PWM and resonant controllers category within the power management segment. It is available in an 8-pin dual-in-line plastic package (DIP) and is compliant with EU RoHS regulations (2011/65/EU, 2015/863).
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Output Current (Source or Sink) | 1.0 | A |
| Maximum Operating Supply Voltage | 30 | V |
| Minimum Operating Supply Voltage | 10 | V |
| Switching Frequency | Up to 500 kHz | Hz |
| Reference Output Voltage | 5.0 | V |
| Line Regulation | ±2.0 mV | mV |
| Load Regulation | ±3.0 mV | mV |
| UVLO Turn-On Threshold | 16 V | V |
| UVLO Turn-Off Threshold | 10 V | V |
| Package Type | 8-Pin DIP or 14-Pin SOIC |
Key Features
- High Performance Current Mode Control: The UC3843AD1R2 operates as a current mode controller, where output switch conduction is initiated by the oscillator and terminated when the peak inductor current reaches a threshold level established by the error amplifier output.
- Trimmed Oscillator: The oscillator frequency is programmable using external timing components RT and CT, allowing for precise duty cycle control.
- Temperature Compensated Reference: A stable 5.0 V reference output with good line and load regulation.
- High Gain Error Amplifier and Current Sensing Comparator: Ensures accurate control over the peak inductor current on a cycle-by-cycle basis.
- High Current Totem Pole Output: Ideal for driving power MOSFETs.
- Protective Features: Includes input and reference undervoltage lockouts with hysteresis, cycle-by-cycle current limiting, programmable output deadtime, and a latch for single pulse metering.
Applications
The UC3843AD1R2 is designed for use in off-line and DC-to-DC converter applications. It is particularly suitable for:
- Switch-mode power supplies.
- DC-DC converters.
- High-efficiency power conversion systems.
- Industrial power supplies.
- Consumer electronics requiring efficient power management.
Q & A
- What is the primary function of the UC3843AD1R2?
The UC3843AD1R2 is a high-performance current mode PWM controller designed for off-line and DC-to-DC converter applications.
- What are the key features of the UC3843AD1R2?
Key features include a trimmed oscillator, temperature compensated reference, high gain error amplifier, current sensing comparator, and protective features such as undervoltage lockouts and cycle-by-cycle current limiting.
- What is the maximum operating supply voltage for the UC3843AD1R2?
The maximum operating supply voltage is 30 V.
- What is the typical reference output voltage of the UC3843AD1R2?
The typical reference output voltage is 5.0 V.
- What types of packages are available for the UC3843AD1R2?
The component is available in 8-pin DIP and 14-pin SOIC packages.
- What are some common applications for the UC3843AD1R2?
Common applications include switch-mode power supplies, DC-DC converters, high-efficiency power conversion systems, industrial power supplies, and consumer electronics requiring efficient power management.
- How is the oscillator frequency programmed in the UC3843AD1R2?
The oscillator frequency is programmed using external timing components RT and CT.
- What protective features does the UC3843AD1R2 include?
The component includes input and reference undervoltage lockouts with hysteresis, cycle-by-cycle current limiting, programmable output deadtime, and a latch for single pulse metering.
- Is the UC3843AD1R2 compliant with EU RoHS regulations?
Yes, the UC3843AD1R2 is compliant with EU RoHS regulations (2011/65/EU, 2015/863).
- What is the maximum output current of the UC3843AD1R2?
The maximum output current is 1.0 A.
