| Pin # | Name | Function | | :--- | :--- | :--- | | 1 | Non-Inverting Input (Error Amp 1) | Usually connected to the voltage feedback. | | 2 | Inverting Input (Error Amp 1) | Connected to a reference voltage. | | 3 | Feedback/PWM Comp | Common point for compensation networks. | | 4 | Dead-Time Control (DTC) | Voltage here controls dead time (0V to 3V). | | 5 | CT | Capacitor for timing oscillator. | | 6 | RT | Resistor for timing oscillator. | | 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 | IC Supply Voltage. | | 13 | Output Control | Selects mode: High = Push-pull, Low = Single-ended. | | 14 | REF | 5V Precision Reference Output. | | 15 | Inverting Input (Error Amp 2) | Usually used for current limiting. | | 16 | Non-Inverting Input (Error Amp 2) | Connected to current sense shunt. |
Error Amp 1 compares the output voltage to the 5V reference. Error Amp 2 monitors voltage across a current shunt (R_shunt) for over-current protection. tl494 circuit diagram
When the MOSFET turns on, current flows through L1 to ground. When it turns off, the magnetic field collapses, forcing current through D1 into the output capacitor at a higher voltage than the input. | Pin # | Name | Function |