The frequency is set by ( R_T ) (pin 6) and ( C_T ) (pin 5):
[ f_osc = \frac1R_T \cdot C_T ]
Example values:
| Application | Configuration | |-------------|---------------| | Boost converter | Single-ended, external MOSFET | | Push-pull inverter | Pin 13 to REF, external transformers | | Battery charger | Use second error amp for current limiting | | Solar MPPT controller | Dual-loop control using both error amps | | ATX power supply modification | Replace original PWM controller |
In many online TL494 circuit diagrams, you will see Pin 4 connected directly to ground. This is a mistake for high-power switching. tl494 circuit diagram
Before diving into circuits, it is crucial to understand the pins. The TL494 is available in DIP-16, SOIC-16, and TSSOP-16 packages.
| Pin No. | Name | Function | |---------|------|----------| | 1 | 1IN+ | Non-inverting input of Error Amplifier 1 | | 2 | 1IN- | Inverting input of Error Amplifier 1 | | 3 | FEEDBACK | PWM comparator input (usually for output voltage control) | | 4 | DTC | Dead-Time Control (sets minimum off-time) | | 5 | CT | Timing Capacitor (sets oscillator frequency) | | 6 | RT | Timing Resistor (sets oscillator frequency) | | 7 | GND | Ground | | 8 | C1 | Collector of Output Transistor 1 | | 9 | E1 | Emitter of Output Transistor 1 | | 10 | E2 | Emitter of Output Transistor 2 | | 11 | C2 | Collector of Output Transistor 2 | | 12 | VCC | Positive supply voltage (7V to 40V) | | 13 | OUT CTRL | Output control (High = Push-Pull mode, Low = Single-ended) | | 14 | REF | 5V Precision Reference Output | | 15 | 2IN- | Inverting input of Error Amplifier 2 | | 16 | 2IN+ | Non-inverting input of Error Amplifier 2 | The frequency is set by ( R_T )
This buck regulator maintains a stable 5V output regardless of input variations or load changes.
The frequency is set by ( R_T ) (pin 6) and ( C_T ) (pin 5):
[ f_osc = \frac1R_T \cdot C_T ]
Example values:
| Application | Configuration | |-------------|---------------| | Boost converter | Single-ended, external MOSFET | | Push-pull inverter | Pin 13 to REF, external transformers | | Battery charger | Use second error amp for current limiting | | Solar MPPT controller | Dual-loop control using both error amps | | ATX power supply modification | Replace original PWM controller |
In many online TL494 circuit diagrams, you will see Pin 4 connected directly to ground. This is a mistake for high-power switching.
Before diving into circuits, it is crucial to understand the pins. The TL494 is available in DIP-16, SOIC-16, and TSSOP-16 packages.
| Pin No. | Name | Function | |---------|------|----------| | 1 | 1IN+ | Non-inverting input of Error Amplifier 1 | | 2 | 1IN- | Inverting input of Error Amplifier 1 | | 3 | FEEDBACK | PWM comparator input (usually for output voltage control) | | 4 | DTC | Dead-Time Control (sets minimum off-time) | | 5 | CT | Timing Capacitor (sets oscillator frequency) | | 6 | RT | Timing Resistor (sets oscillator frequency) | | 7 | GND | Ground | | 8 | C1 | Collector of Output Transistor 1 | | 9 | E1 | Emitter of Output Transistor 1 | | 10 | E2 | Emitter of Output Transistor 2 | | 11 | C2 | Collector of Output Transistor 2 | | 12 | VCC | Positive supply voltage (7V to 40V) | | 13 | OUT CTRL | Output control (High = Push-Pull mode, Low = Single-ended) | | 14 | REF | 5V Precision Reference Output | | 15 | 2IN- | Inverting input of Error Amplifier 2 | | 16 | 2IN+ | Non-inverting input of Error Amplifier 2 |
This buck regulator maintains a stable 5V output regardless of input variations or load changes.
