Overview
The UC3842AD8 is a current-mode PWM controller from Texas Instruments, designed for off-line and DC-DC converter applications. It is part of the UCx84xA family, which offers improved features over the UCx84x family. This device is optimized for controlling current-mode or switched-mode power supplies with a minimal number of external components. The UC3842AD8 operates within a temperature range of 0°C to 70°C and is available in an 8-pin SOIC (D) package.
Key Specifications
| Parameter | Symbol | Value | Unit |
|---|---|---|---|
| Supply Voltage | VCC | 30 | V |
| Output Current | IO | ±1 | A |
| Analog Inputs (Pin 2, 3) | V(ANA) | -0.3 to 6.3 | V |
| Error Amp Output Sink Current | ISINK (E.A) | 10 | mA |
| Power Dissipation at TA≤25°C (8DIP) | PD | 1200 | mW |
| Storage Temperature Range | TSTG | -65 ~ +150 | °C |
| Oscillation Frequency | f | 47 to 57 | kHz |
| Reference Output Voltage | VREF | 4.90 to 5.10 | V |
| UVLO Start Threshold | VTH(ST) | 14.5 to 17.5 | V |
| UVLO Minimum Operating Voltage | VOPR(MIN) | 8.5 to 11.5 | V |
Key Features
- Optimized for off-line and DC-DC converters
- Low start-up current (< 0.5mA)
- Trimmed oscillator discharge current
- Automatic feedforward compensation
- Pulse-by-pulse current limiting
- Enhanced load response characteristics
- Undervoltage lockout with hysteresis
- Double pulse suppression
- High-current totem pole output
- Internally-trimmed bandgap reference
- Up to 500kHz operation
- Error amplifier with low output resistance
Applications
- Switching regulators of any polarity
- Transformer-coupled DC-DC converters
- Off-line power supplies
- DC-DC converter applications with minimum external components
Q & A
- What is the operating temperature range of the UC3842AD8?
The UC3842AD8 operates within a temperature range of 0°C to 70°C.
- What is the maximum supply voltage for the UC3842AD8?
The maximum supply voltage is 30V.
- What is the output current capability of the UC3842AD8?
The output current is ±1A.
- What is the oscillation frequency range of the UC3842AD8?
The oscillation frequency range is 47 to 57 kHz.
- Does the UC3842AD8 have undervoltage lockout (UVLO) with hysteresis?
Yes, it has UVLO with hysteresis. The start threshold is between 14.5V and 17.5V, and the minimum operating voltage after turn-on is between 8.5V and 11.5V.
- What is the package type and pin count of the UC3842AD8?
The UC3842AD8 is available in an 8-pin SOIC (D) package.
- What are some key features of the UC3842AD8?
Key features include low start-up current, trimmed oscillator discharge current, automatic feedforward compensation, pulse-by-pulse current limiting, and a high-current totem pole output.
- Can the UC3842AD8 operate at 100% duty cycle?
Yes, the UC3842AD8 can operate within a 100% duty cycle.
- What types of applications is the UC3842AD8 suitable for?
The UC3842AD8 is suitable for switching regulators, transformer-coupled DC-DC converters, off-line power supplies, and DC-DC converter applications.
- Is the UC3842AD8 still in production?
No, the UC3842AD8 is no longer in production and is listed as obsolete.
