Overview
The UCC28C45DR is a high-performance, low-power current-mode PWM (Pulse Width Modulation) controller produced by Texas Instruments. This device is part of the UCCx8C4x family, which offers enhanced replacements for the industry-standard UCx84x and UCx84xA families with pin-to-pin compatibility. The UCC28C45DR is designed to operate in a wide temperature range from –40°C to 125°C, making it suitable for various industrial applications. It utilizes BiCMOS technology to achieve lower power consumption, faster current sense, and higher oscillator frequency, thereby improving overall efficiency and performance.
Key Specifications
| Parameter | Min | Typ | Max | Unit |
|---|---|---|---|---|
| Operating Frequency | - | - | 1 MHz | - |
| Startup Current | 50 µA | - | 100 µA | - |
| Operating Current (at fOSC = 52kHz) | - | 2.3 mA | - | - |
| Peak Driving Current | - | ±1 A | - | - |
| Rise Time | 25 ns | - | 50 ns | - |
| Fall Time | 20 ns | - | 40 ns | - |
| Error Amplifier Reference Voltage | 4.9 V | 5 V | 5.1 V | - |
| Undervoltage Lockout (VDDON) | 7.8 V | 8.4 V | 9 V | - |
| Minimum Operating Voltage (VDDOFF) | 7 V | 7.6 V | 8.2 V | - |
| Maximum Duty Cycle | - | - | 96% | - |
| Package Type | - | - | SOIC (D) 8-pin | - |
| Operating Temperature Range | -40°C | - | 125°C | - |
Key Features
- Enhanced replacement for UCx84x and UCx84xA family with pin-to-pin compatibility.
- Operating frequency up to 1 MHz, suitable for high-speed applications.
- Low startup current of 50 µA and maximum operating current of 100 µA.
- Fast, cycle-by-cycle overcurrent limiting with a delay time of 35 ns.
- Peak driving current of ±1 A with rail-to-rail output.
- Trimmed oscillator discharge current for precise duty cycle and dead-time control.
- Undervoltage lockout protections with start threshold of 8.4 V and minimum operating voltage of 7.6 V.
- ±1% accurate 2.5 V error amplifier reference voltage.
- Compact VSSOP-8 and SOIC (D) 8-pin packages to minimize board space.
Applications
The UCC28C45DR is designed for use in various power supply applications, including:
- Fixed frequency, peak current-mode power supplies.
- Battery systems, particularly with lower startup voltage versions.
- High-speed and high-efficiency power conversion systems.
- Industrial power supplies requiring a wide operating temperature range.
- Applications needing fast current sense and oscillator frequency.
Q & A
- What is the maximum operating frequency of the UCC28C45DR?
The maximum operating frequency is 1 MHz.
- What is the startup current of the UCC28C45DR?
The startup current is 50 µA.
- What is the peak driving current capability of the UCC28C45DR?
The peak driving current is ±1 A.
- What is the accuracy of the error amplifier reference voltage?
The error amplifier reference voltage is accurate to ±1% at 2.5 V.
- What are the package options available for the UCC28C45DR?
The device is available in 8-pin VSSOP (DGK) and 8-pin SOIC (D) packages.
- What is the operating temperature range of the UCC28C45DR?
The operating temperature range is from –40°C to 125°C.
- What is the undervoltage lockout start threshold for the UCC28C45DR?
The undervoltage lockout start threshold is 8.4 V.
- What is the minimum operating voltage for the UCC28C45DR?
The minimum operating voltage is 7.6 V.
- What is the maximum duty cycle of the UCC28C45DR?
The maximum duty cycle is 96%.
- What is the delay time for the current-sense-to-output in the UCC28C45DR?
The delay time is 35 ns.
