Overview
The UC3842ADWG4 is a fixed frequency current-mode PWM (Pulse Width Modulation) controller manufactured by Unitrode, which is now part of Texas Instruments. This integrated circuit is specifically designed for off-line and DC to DC converter applications, requiring minimal external components. It is optimized for efficient power sequencing and driving power MOSFETs or transistors.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Manufacturer | Unitrode (Texas Instruments) | |
| Category | PMIC - AC DC Converters, Offline Switchers | |
| Description | IC REG CTRLR PWM CM 16SOIC | |
| Package | 16-SOIC (0.295", 7.50mm Width) | |
| Operating Temperature | 0°C ~ 70°C (TA) | |
| Mounting Type | Surface Mount | |
| Voltage - Supply (Vcc/Vdd) | 10V ~ 30V | |
| Frequency - Switching | Up to 500kHz | |
| Duty Cycle (Max) | 100% (UC3842/UC3843), 50% (UC3844/UC3845) | |
| Topology | Boost, Buck, Flyback, Forward | |
| Output Type | Transistor Driver | |
| Output Configuration | Positive, Isolation Capable | |
| Number of Outputs | 1 | |
| Output Phases | 1 | |
| UVLO Thresholds | 16V (on), 10V (off) for UC3842/UC3844; 8.5V (on), 7.9V (off) for UC3843/UC3845 |
Key Features
- Low start-up current
- Maximum duty cycle clamp
- UVLO (Under-Voltage Lock-Out) with hysteresis
- Operating frequency up to 500kHz
- 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
- Frequency control features
Applications
The UC3842ADWG4 is designed for various power supply applications, including:
- Off-line converters
- DC to DC regulators
- Flyback and forward converters
- Power sequencing in switch-mode power supplies
Q & A
- What is the operating voltage range of the UC3842ADWG4?
The UC3842ADWG4 operates within a supply voltage range of 10V to 30V.
- What is the maximum switching frequency of the UC3842ADWG4?
The maximum switching frequency is up to 500kHz.
- What are the UVLO thresholds for the UC3842ADWG4?
The UVLO thresholds are 16V (on) and 10V (off) for UC3842/UC3844, and 8.5V (on) and 7.9V (off) for UC3843/UC3845.
- What is the maximum duty cycle for the UC3842ADWG4?
The maximum duty cycle is approximately 100% for UC3842/UC3843 and 50% for UC3844/UC3845.
- What are the typical applications of the UC3842ADWG4?
Typical applications include off-line converters, DC to DC regulators, flyback and forward converters, and power sequencing in switch-mode power supplies.
- What is the package type of the UC3842ADWG4?
The package type is 16-SOIC (0.295", 7.50mm Width).
- Does the UC3842ADWG4 have internal switches?
No, the UC3842ADWG4 does not have internal switches.
- What is the operating temperature range of the UC3842ADWG4?
The operating temperature range is 0°C to 70°C (TA).
- What are the key features of the UC3842ADWG4?
Key features include low start-up current, UVLO with hysteresis, trimmed oscillator, temperature-compensated reference, high gain error amplifier, and high current totem-pole output.
- Is the UC3842ADWG4 RoHS compliant?
Yes, the UC3842ADWG4 is RoHS compliant.
