Overview
The UC2875N is a bipolar phase-shifted full-bridge controller integrated circuit produced by Texas Instruments. This device is designed to control a bridge power stage by phase-shifting the switching of one half-bridge with respect to the other, enabling constant frequency pulse-width modulation combined with resonant, zero-voltage switching for high efficiency performance at high frequencies. The UC2875N can operate in either voltage or current mode and includes features such as programmable time delays, soft-start control, and over-current protection. It is available in various packages, including 20-pin PDIP, 28-pin SOIC, and 28-lead PLCC, and operates over a temperature range of -25°C to 85°C.
Key Specifications
| Parameter | Description |
|---|---|
| Package | PDIP-20, SOIC-28, PLCC-28 |
| Pins | 20 (PDIP), 28 (SOIC and PLCC) |
| Operating Temperature Range | -25°C to 85°C |
| Maximum Operating Supply Voltage | 20V |
| Maximum Operating Current | 2A per output |
| Number of Outputs | 4 |
| Switching Frequency | Up to 1MHz |
| Error Amplifier Bandwidth | Exceeds 7MHz |
| Undervoltage Lockout (UVLO) | 10.75V with 1.5V hysteresis |
Key Features
- Zero to 100% Duty Cycle Control
- Programmable Output Turn-On Delay
- Compatible with Voltage or Current Mode Topologies
- Practical Operation at Switching Frequencies to 1MHz
- Four 2A Totem Pole Outputs
- 10MHz Error Amplifier
- Undervoltage Lockout (UVLO) with 1.5V hysteresis
- Low Startup Current (150µA)
- Outputs Active Low During UVLO
- Soft-Start Control
- Latched Over-Current Comparator With Full Cycle Restart
- Trimmed Reference and Flexible Ramp Generation and Slope Compensation Circuitry
Applications
The UC2875N is suitable for various power management applications, including:
- High-efficiency DC-DC converters using resonant or zero-voltage switching techniques.
- Bridge power stages in both voltage and current mode operations.
- Applications requiring high-frequency switching and precise control over output stages.
- Power supplies where soft-start, over-current protection, and undervoltage lockout are essential.
Q & A
- What is the primary function of the UC2875N?
The UC2875N is a bipolar phase-shifted full-bridge controller designed to control a bridge power stage for high-efficiency power conversion.
- What are the available package types for the UC2875N?
The UC2875N is available in 20-pin PDIP, 28-pin SOIC, and 28-lead PLCC packages.
- What is the operating temperature range of the UC2875N?
The operating temperature range is -25°C to 85°C.
- What is the maximum switching frequency of the UC2875N?
The UC2875N can operate at switching frequencies up to 1MHz.
- Does the UC2875N support both voltage and current mode operations?
- What protective features does the UC2875N include?
The UC2875N includes undervoltage lockout, over-current protection with full-cycle restart, and soft-start control.
- How many outputs does the UC2875N have?
The UC2875N has four 2A totem pole outputs.
- What is the bandwidth of the error amplifier in the UC2875N?
The error amplifier bandwidth exceeds 7MHz.
- Can the UC2875N be synchronized with an external clock signal?
- What is the purpose of the programmable output turn-on delay in the UC2875N?
The programmable output turn-on delay allows for the insertion of a dead-time at the turn-on of each output stage, which is crucial for resonant switching action.
- Is the UC2875N RoHS compliant?
