Overview
The TL594IDRG4, produced by Texas Instruments, is a pulse-width-modulation (PWM) control circuit designed primarily for power-supply control. This device integrates all the necessary functions for constructing a PWM control circuit on a single chip, offering flexibility to tailor the power-supply control circuitry to specific applications. The TL594 is suitable for a wide range of switching converter applications, including AC/DC power supplies, solar micro-inverters, and server power supplies.
Key Specifications
| Parameter | Min | Typ | Max | Unit |
|---|---|---|---|---|
| VCC (Supply Voltage) | 7 | - | 40 | V |
| Oscillator Frequency Range | 1 Hz | - | 300 kHz | - |
| Output Current (each transistor) | - | - | 200 mA | - |
| Saturation Voltage (common-emitter) | - | - | 1.3 V | - |
| Saturation Voltage (emitter-follower) | - | - | 2.5 V | - |
| Operating Temperature Range | 0°C | - | 70°C | - |
| Package Types | SOIC (16), PDIP (16), SO (16), TSSOP (16) | - | - | - |
Key Features
- Complete PWM power-control circuitry on a single chip.
- Two error amplifiers with a common-mode voltage range of –0.3 V to VCC – 2 V.
- An on-chip adjustable oscillator with a frequency range of 1 Hz to 300 kHz.
- A dead-time control (DTC) comparator providing approximately 5% dead time.
- A pulse-steering control flip-flop for alternating output pulses.
- A 5-V regulator with 1% precision and thermal stability.
- Undervoltage lockout (UVLO) circuitry for low-VCC conditions.
- Output control circuitry allowing single-ended or push-pull operation.
- Uncommitted output transistors capable of sinking or sourcing up to 200 mA.
Applications
- AC/DC power supplies: isolated with or without power factor correction (PFC), > 90 W and < 90 W.
- Server power supplies.
- Solar micro-inverters and solar power inverters.
- Telecom/server AC/DC supplies.
- White goods and other consumer electronics.
Q & A
- What is the primary function of the TL594?
The TL594 is a pulse-width-modulation (PWM) control circuit designed primarily for power-supply control.
- What is the range of the oscillator frequency in the TL594?
The oscillator frequency range is from 1 Hz to 300 kHz.
- How does the TL594 handle undervoltage conditions?
The TL594 has an undervoltage lockout (UVLO) circuit that shuts off the device if the VCC voltage drops below 6 V.
- What types of output operations are supported by the TL594?
The TL594 supports single-ended or push-pull output operations, selectable via the OUTPUT CTRL pin.
- What is the precision of the internal 5-V regulator in the TL594?
The internal 5-V regulator has a precision of 1% and maintains thermal stability.
- How much current can each output transistor handle?
Each output transistor can sink or source up to 200 mA.
- What are the common package types for the TL594?
The TL594 is available in SOIC (16), PDIP (16), SO (16), and TSSOP (16) packages.
- What is the operating temperature range for the TL594?
The operating temperature range is from 0°C to 70°C.
- Can the TL594 be used in synchronous multiple-rail power supplies?
- How is the dead time controlled in the TL594?
The dead time is controlled by the DTC comparator, which provides approximately 5% dead time.
