on video 167 Difference between sg3525 and TL494

167 Difference between sg3525 and TL494

Today we are going to findout which ic is best for our projects tl494 vs SG3525.

As we know SG3525 ic is very popular in various SMPS or high frequency devices. These ics has lots of function.

SG3525

The SG3525A, SG3527A pulse width modulator control circuits offer

improved performance and lower external parts count when implemented for

controlling all types of switching power supplies. The on–chip +5.1 V

reference is trimmed to ±1% and the error amplifier has an input

common–mode voltage range that includes the reference voltage, thus

Eliminate the need for external divider resistors. A sync input to the

oscillator enables multiple units to be slaved or a single unit to be

synchronized to an external system clock. A wide range of deadtime can be

Programmed by a single resistor connected between the CT and Discharge

pins. These devices also feature built-in soft-start circuitry, requiring only an

external timing capacitor. A shutdown pin controls both the soft–start circuitry

and the output stages, providing instantaneous turn off through the PWM

latch with pulsed shutdown, as well as soft – start recycle with longer

shutdown commands. The under voltage lockout inhibits the outputs and the

Changing of the soft–start capacitor when VCC is below nominal. The output

Stages are totem–pole design capable of sinking and sourcing in excess of

200mA. The output stage of the SG3525A features NOR logic resulting in a

low output for an off-state while the SG3527A utilized OR logic which gives a

high output when off.

• 8.0 V to 35 V operation

• 5.1 V ± 1.0% Trimmed Reference

• 100 Hz to 400 kHz Oscillator Range

• Separate Oscillator Sync Pin

• Adjustable Deadtime Control

• Input Undervoltage Lockout

• Latching PWM to Prevent Multiple Pulses

• Pulse–by–Pulse Shutdown

• Dual Source/Sink Outputs: ±400 mA Peak

TL494 is also popular across Computer PSU because it is made to drive transisters.

Complete PWM Power-Control Circuitry

• Uncommitted Outputs for 200-mA Sink or

Source Current

• Output Control Selects Single-Ended or

Push-Pull Operation

• Internal Circuitry Prohibits Double Pulse at

Either Output

• Variable Dead Time Provides Control Over

Total Range

• Internal Regulator Provides a Stable 5-V

Reference Supply With 5% Tolerance

• Circuit Architecture Allows Easy

Synchronization

The TL494 incorporates all the functions required in the construction of a pulse-width-modulation (PWM) control

circuit on a single chip. Designed primarily for power-supply control, this device offers the flexibility to tailor the power-supply control circuitry to a specific application.

The TL494 contains two error amplifiers, an on-chip adjustable oscillator, a dead-time control (DTC) comparator,

a pulse-steering control flip-flop, a 5-V, 5%-precision regulator, and output-control circuits.

The error amplifiers exhibit a common-mode voltage range from –0.3 V to VCC – 2 V. The dead-time control

The comparator has a fixed offset that provides approximately 5% dead time. The on-chip oscillator can be bypassed

by terminating RT to the reference output and providing a sawtooth input to CT, or it can drive the common

circuits in synchronous multiple-rail power supplies.

The uncommitted output transistors provide either common-emitter or emitter-follower output capability. The

TL494 provides for push-pull or single-ended output operation, which can be selected through the output-control

function. The architecture of this device prohibits the possibility of either output being pulsed twice during

push-pull operation.

The TL494C is characterized for operation from 0°C to 70°C. The TL494I is characterized for operation from

–40°C to 85°C.