Overview
The UC3845DTR is a single-ended current-mode PWM (Pulse Width Modulation) controller produced by Texas Instruments. This integrated circuit is part of the UCx84x family, which is optimized for off-line and DC-to-DC converters. The UC3845DTR is designed to operate with a minimum number of external components, making it a versatile and efficient choice for various power supply applications.
The device features a range of internal circuits, including an undervoltage lockout (UVLO) with hysteresis, a precision reference, and a totem-pole output stage capable of sourcing or sinking high-peak current. This makes it suitable for driving N-channel MOSFETs in power conversion systems.
Key Specifications
| Parameter | Value |
|---|---|
| Package | 14-Pin SOIC (D) |
| Operating Temperature Range | 0°C to 70°C |
| Switching Frequency | Up to 500 kHz |
| Output Current | 200 mA |
| UVLO Thresholds | 8.4 V / 7.6 V |
| Duty Cycle | 50% |
| Start-up Current | < 1 mA |
| RoHS Compliance | Yes |
Key Features
- Optimized for off-line and DC-to-DC converters
- Low start-up current (< 1 mA)
- Automatic feedforward compensation
- Pulse-by-pulse current limiting
- Enhanced load-response characteristics
- Undervoltage lockout with hysteresis
- Double-pulse suppression
- High-current totem-pole output
- Internally trimmed bandgap reference
- Error amplifier with low output resistance
Applications
The UC3845DTR is widely used in various power supply applications, including:
- Off-line power supplies
- DC-to-DC converters
- Switch-mode power supplies
- High-frequency power conversion systems
Q & A
- What is the operating temperature range of the UC3845DTR?
The operating temperature range of the UC3845DTR is from 0°C to 70°C.
- What is the maximum switching frequency of the UC3845DTR?
The UC3845DTR can operate up to a switching frequency of 500 kHz.
- What is the UVLO threshold for the UC3845DTR?
The UVLO thresholds for the UC3845DTR are 8.4 V and 7.6 V.
- What is the maximum output current of the UC3845DTR?
The maximum output current of the UC3845DTR is 200 mA.
- Is the UC3845DTR RoHS compliant?
Yes, the UC3845DTR is RoHS compliant.
- What type of package does the UC3845DTR come in?
The UC3845DTR comes in a 14-Pin SOIC (D) package.
- What is the start-up current of the UC3845DTR?
The start-up current of the UC3845DTR is less than 1 mA.
- What are some key features of the UC3845DTR?
Key features include low start-up current, automatic feedforward compensation, pulse-by-pulse current limiting, and an internally trimmed bandgap reference.
- In what types of applications is the UC3845DTR commonly used?
The UC3845DTR is commonly used in off-line power supplies, DC-to-DC converters, and high-frequency power conversion systems.
- How does the UC3845DTR enhance load-response characteristics?
The UC3845DTR enhances load-response characteristics through its internal circuits, including the error amplifier and current-limiting features.
