Overview
The UC3846QTR/80198 is a current-mode PWM controller from Unitrode, now part of Texas Instruments. This device is part of the UCx846/7 family, which is designed to implement fixed-frequency, current-mode control schemes with a minimal external parts count. It is particularly useful in off-line or DC-to-DC power conversion applications, offering a range of features that enhance performance, reliability, and ease of design.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Supply Voltage (Vcc/Vdd) | 6.95V ~ 40V | V |
| Switching Frequency | 500kHz | kHz |
| Maximum Duty Cycle | 50% | % |
| Output Current, Source or Sink | 500 mA | mA |
| Reference Output Voltage | 5.05 - 5.15 V | V |
| Under-Voltage Lockout Start-Up Threshold | 7.7 - 8.0 V | V |
| Operating Temperature Range | 0°C to +70°C | °C |
Key Features
- Automatic Feedforward Compensation: Enhances line regulation and load response characteristics.
- Programmable Pulse-by-Pulse Current Limiting: Provides inherent current limiting capability.
- Automatic Symmetry Correction in Push-Pull Configuration: Ensures balanced operation in push-pull converters.
- Enhanced Load Response Characteristics: Improves the dynamic response of the power supply.
- Parallel Operation Capability: Allows multiple power modules to operate in parallel with equal current sharing.
- Differential Current Sense Amplifier with Wide Common Mode Range: Flexible current sensing options.
- Double-Pulse Suppression Protection: Prevents double-pulse errors.
- Undervoltage Lockout and Soft-Start Capability: Ensures safe startup and operation.
- Shutdown Terminal: Allows for external shutdown control.
- ±1% Band Gap Reference: Provides a stable reference voltage.
Applications
- Telecommunication Power Converters: Suitable for high-reliability power supplies in telecommunications equipment.
- Industrial Power Converters: Used in various industrial power conversion applications requiring high efficiency and reliability.
- DC-to-DC Converters: Ideal for fixed-frequency, current-mode controlled DC-to-DC conversion systems.
- Off-Line Power Supplies: Applicable in off-line power supplies that require robust and efficient control.
Q & A
- What is the typical switching frequency of the UC3846QTR/80198?
The typical switching frequency is 500 kHz.
- What is the maximum duty cycle of the UC3846QTR/80198?
The maximum duty cycle is 50%.
- What is the output current capability of the UC3846QTR/80198?
The device can source or sink up to 500 mA.
- What is the reference output voltage of the UC3846QTR/80198?
The reference output voltage is typically between 5.05 V and 5.15 V.
- What is the under-voltage lockout start-up threshold for the UC3846QTR/80198?
The under-voltage lockout start-up threshold is between 7.7 V and 8.0 V.
- Can the UC3846QTR/80198 be used in parallel operation?
Yes, it supports parallel operation with equal current sharing.
- What is the operating temperature range of the UC3846QTR/80198?
The operating temperature range is from 0°C to +70°C.
- Does the UC3846QTR/80198 have built-in undervoltage lockout and soft-start capability?
Yes, it includes both undervoltage lockout and soft-start capability.
- What is the purpose of the shutdown terminal on the UC3846QTR/80198?
The shutdown terminal allows for external control of the device's shutdown state.
- What type of applications is the UC3846QTR/80198 typically used in?
It is typically used in telecommunication power converters, industrial power converters, DC-to-DC converters, and off-line power supplies.
