Overview
The UC1843AMDREPG4 is a current-mode PWM (Pulse Width Modulation) controller from Texas Instruments, part of the UC184x family. This device is designed to control current-mode switched-mode power supplies and offers several improved features over its predecessors. It is pin-for-pin compatible with the UC384x family and is known for its enhanced load response characteristics, under-voltage lockout with hysteresis, and double pulse suppression. The UC1843AMDREPG4 operates within a military temperature range of -55°C to 125°C, making it suitable for a wide range of applications, including those in harsh environments.
Key Specifications
| Parameter | Minimum | Typical | Maximum | Units |
|---|---|---|---|---|
| VCC Voltage (Low Impedance Source) | 30 | V | ||
| Output Current, IO | ±1 A | A | ||
| Start-up Current | 0.3 | 0.5 | mA | |
| Operating Supply Current | 11 | 17 | mA | |
| Maximum Duty Cycle | 94% | 96% | 100% | % |
| UVLO Start Threshold | 7.8 | 8.4 | 9 | V |
| UVLO Minimum Operation Voltage After Turn On | 7 | 7.6 | 8.2 | V |
| Oscillator Frequency | Up to 500 kHz | kHz |
Key Features
- Enhanced Load Response Characteristics: Improved performance in handling load changes.
- Under-Voltage Lockout With Hysteresis: Ensures the device operates only when the input voltage is within a safe range.
- Double Pulse Suppression: Prevents unwanted double pulses that can occur during startup or fault conditions.
- High Current Totem Pole Output: Capable of sourcing and sinking high currents.
- Internally Trimmed Bandgap Reference: Provides a stable reference voltage.
- 500 kHz Operation: Supports high-frequency switching applications.
- Low RO Error Amp: Minimizes errors in the error amplifier section.
- Start-up Current Less Than 0.5 mA: Low power consumption during startup.
- Oscillator Discharge Trimmed to 8.3 mA: Precise control over the oscillator discharge current.
Applications
- Switched-Mode Power Supplies: Suitable for various topologies such as flyback, forward, buck, boost, push-pull, half-bridge, and full-bridge configurations.
- High-Reliability Systems: Given its military temperature range and radiation-hardened options, it is ideal for aerospace, defense, and other high-reliability applications.
- Industrial Power Supplies: Used in industrial power supplies that require robust and reliable operation.
- Automotive Systems: Can be used in automotive systems that need to operate over a wide temperature range.
Q & A
- What is the operating temperature range of the UC1843AMDREPG4?
The UC1843AMDREPG4 operates within a temperature range of -55°C to 125°C.
- What is the maximum duty cycle for the UC1843AMDREPG4?
The maximum duty cycle for the UC1843AMDREPG4 is up to 100%.
- What is the start-up current of the UC1843AMDREPG4?
The start-up current is guaranteed to be less than 0.5 mA.
- What is the under-voltage lockout (UVLO) start threshold for the UC1843AMDREPG4?
The UVLO start threshold is between 7.8 V and 9 V.
- What is the maximum output current of the UC1843AMDREPG4?
The maximum output current is ±1 A.
- What is the oscillator frequency range for the UC1843AMDREPG4?
The oscillator frequency can operate up to 500 kHz.
- What type of packaging is available for the UC1843AMDREPG4?
The device is available in SOIC (Small Outline Integrated Circuit) packaging.
- Is the UC1843AMDREPG4 radiation-hardened?
Yes, the UC1843AMDREPG4 is available in radiation-hardened versions, such as the UC1843A-SP.
- What are some common applications for the UC1843AMDREPG4?
Common applications include switched-mode power supplies, high-reliability systems, industrial power supplies, and automotive systems.
- How does the UC1843AMDREPG4 handle double pulses during startup?
The device features double pulse suppression to prevent unwanted double pulses during startup or fault conditions.
