Thông số kỹ thuật
| thuộc tính | Giá trị |
| Package | Bulk,Tube |
| ProductStatus | Active |
| OutputType | Transistor Driver |
| Function | Step-Up, Step-Up/Step-Down |
| OutputConfiguration | Positive, Isolation Capable |
| Topology | Boost, Flyback |
| NumberofOutputs | 1 |
| OutputPhases | 1 |
| Voltage-Supply(Vcc/Vdd) | 7.6V ~ 30V |
| Frequency-Switching | Up to 500kHz |
| DutyCycle(Max) | 48% |
| SynchronousRectifier | No |
| ClockSync | No |
| ControlFeatures | Frequency Control |
| OperatingTemperature | -25°C ~ 85°C (TA) |
| MountingType | Surface Mount |
| Package/Case | 8-SOIC (0.154, 3.90mm Width) |
Tổng quan
Description
The UC2845BD1G is a fixed-frequency current-mode PWM (Pulse Width Modulation) controller designed for off-line and DC-to-DC converter applications. It is part of the UC284x family and is manufactured by ON Semiconductor. This device is engineered to provide precise control of power supplies, offering improved performance and efficiency.
Key features of the UC2845BD1G include:
1. Current Mode Control: Enhances system performance by offering cycle-by-cycle current limiting.
2. Fixed Frequency Oscillator: Typically operates at 100 kHz, ensuring consistent performance in power conversion applications.
3. High Current Totem Pole Output: Capable of driving power MOSFET gates directly.
4. Undervoltage Lockout (UVLO): Ensures the power supply operates only when sufficient voltage is present, preventing instability.
5. Low Startup and Operating Current: Enhances efficiency and reduces thermal stress.
6. Wide Operating Voltage Range: Accommodates various input conditions for diverse applications.
The UC2845BD1G is commonly used in switch-mode power supplies, motor controllers, and other applications requiring efficient power conversion and regulation.
Key features of the UC2845BD1G include:
1. Current Mode Control: Enhances system performance by offering cycle-by-cycle current limiting.
2. Fixed Frequency Oscillator: Typically operates at 100 kHz, ensuring consistent performance in power conversion applications.
3. High Current Totem Pole Output: Capable of driving power MOSFET gates directly.
4. Undervoltage Lockout (UVLO): Ensures the power supply operates only when sufficient voltage is present, preventing instability.
5. Low Startup and Operating Current: Enhances efficiency and reduces thermal stress.
6. Wide Operating Voltage Range: Accommodates various input conditions for diverse applications.
The UC2845BD1G is commonly used in switch-mode power supplies, motor controllers, and other applications requiring efficient power conversion and regulation.
Equivalent
The UC2845BD1G is a current-mode PWM controller often used in power supply applications. Equivalent products include the UC3845 series (such as UC3845AN or UC3845BN), TL3845, and LM3845. These ICs are functionally similar and are used in similar applications, but you should verify specifications and pin compatibility before interchange.
Features
The UC2845BD1G is a high-performance fixed-frequency current-mode controller designed for switch-mode power supplies. Key features include:
1. Current Mode Control: Provides improved performance and transient response by directly controlling the peak current in the power switch.
2. Fixed Operating Frequency: Typically set at 100 kHz, which can be adjusted using an external resistor, allowing for flexibility in application designs.
3. Low Start-Up Current: Minimizes power consumption during startup, enhancing efficiency.
4. High Output Current Capability: Drives power MOSFETs with up to 1 A peak current, suitable for demanding power supply designs.
5. Undervoltage Lockout (UVLO): Ensures the controller operates within safe voltage levels, with separate thresholds for turn-on and turn-off.
6. Leading Edge Blanking: Reduces noise sensitivity and prevents false triggering of the current sense comparator.
7. Soft Start: Gradually increases the duty cycle during startup, reducing stress on power components.
8. Wide Operating Temperature Range: Supports industrial applications with reliable performance from -40°C to +85°C.
These features make the UC2845BD1G suitable for a variety of power supply applications, including isolated and non-isolated topologies.
1. Current Mode Control: Provides improved performance and transient response by directly controlling the peak current in the power switch.
2. Fixed Operating Frequency: Typically set at 100 kHz, which can be adjusted using an external resistor, allowing for flexibility in application designs.
3. Low Start-Up Current: Minimizes power consumption during startup, enhancing efficiency.
4. High Output Current Capability: Drives power MOSFETs with up to 1 A peak current, suitable for demanding power supply designs.
5. Undervoltage Lockout (UVLO): Ensures the controller operates within safe voltage levels, with separate thresholds for turn-on and turn-off.
6. Leading Edge Blanking: Reduces noise sensitivity and prevents false triggering of the current sense comparator.
7. Soft Start: Gradually increases the duty cycle during startup, reducing stress on power components.
8. Wide Operating Temperature Range: Supports industrial applications with reliable performance from -40°C to +85°C.
These features make the UC2845BD1G suitable for a variety of power supply applications, including isolated and non-isolated topologies.
Pinout
The UC2845BD1G is a current-mode PWM controller typically used in DC-DC converters and off-line switching power supplies. It is commonly available in an 8-pin package. Here is a brief overview of its pins and functions:
1. Pin 1 (Compensation): Used for frequency compensation of the control loop.
2. Pin 2 (Voltage Feedback): Receives feedback voltage from the output to regulate the output voltage.
3. Pin 3 (Current Sense): Monitors the inductor current for current limiting purposes.
4. Pin 4 (RT/CT): Sets the oscillator frequency with an external resistor and capacitor.
5. Pin 5 (Ground): Common ground reference for all the control circuitry.
6. Pin 6 (Output): Drives the gate of an external MOSFET or a power transistor.
7. Pin 7 (VCC): Power supply pin for the IC.
8. Pin 8 (VREF): Provides a stable 5V reference output for internal and external circuitry.
The UC2845BD1G is designed for high-performance and low-cost applications, offering features like high-speed current limiting, under-voltage lockout, and a start-up current of less than 1 mA.
1. Pin 1 (Compensation): Used for frequency compensation of the control loop.
2. Pin 2 (Voltage Feedback): Receives feedback voltage from the output to regulate the output voltage.
3. Pin 3 (Current Sense): Monitors the inductor current for current limiting purposes.
4. Pin 4 (RT/CT): Sets the oscillator frequency with an external resistor and capacitor.
5. Pin 5 (Ground): Common ground reference for all the control circuitry.
6. Pin 6 (Output): Drives the gate of an external MOSFET or a power transistor.
7. Pin 7 (VCC): Power supply pin for the IC.
8. Pin 8 (VREF): Provides a stable 5V reference output for internal and external circuitry.
The UC2845BD1G is designed for high-performance and low-cost applications, offering features like high-speed current limiting, under-voltage lockout, and a start-up current of less than 1 mA.
Manufacturer
The UC2845BD1G is manufactured by ON Semiconductor, now known as onsemi. onsemi is a leading company in the semiconductor industry, specializing in the design and manufacture of a wide range of semiconductor components. These components serve various applications, including automotive, industrial, consumer electronics, and communications. onsemi focuses on energy-efficient solutions, providing products that enhance power management and optimize energy usage in electronic systems.
Application
The UC2845BD1G is a high-performance, fixed-frequency, current-mode PWM controller often used in applications where efficient and precise power management is required. Common application areas include:
1. Switch-Mode Power Supplies (SMPS): Used in AC-DC and DC-DC converters.
2. Power Adapters: Suitable for consumer electronics requiring efficient power conversion.
3. Battery Chargers: Provides precise control for charging circuits.
4. LED Drivers: Used in controlling and regulating LED lighting systems.
5. Industrial Control Systems: Helps in managing power in automation equipment.
6. Telecom Power Supplies: Ensures stable power supply in telecom infrastructure.
These applications benefit from the IC's stability, adjustable output voltage, and built-in protection features.
1. Switch-Mode Power Supplies (SMPS): Used in AC-DC and DC-DC converters.
2. Power Adapters: Suitable for consumer electronics requiring efficient power conversion.
3. Battery Chargers: Provides precise control for charging circuits.
4. LED Drivers: Used in controlling and regulating LED lighting systems.
5. Industrial Control Systems: Helps in managing power in automation equipment.
6. Telecom Power Supplies: Ensures stable power supply in telecom infrastructure.
These applications benefit from the IC's stability, adjustable output voltage, and built-in protection features.
Package
The UC2845BD1G is typically available in a SOIC-8 (Small Outline Integrated Circuit) package, which is a surface-mount package with 8 pins, commonly used for integrated circuits in various electronic applications.
