TL1464I

QUAD PULSE-WIDTH-MODULATION CONTROL CIRCUIT

SLVS266 – FEBRUARY 2000

8

POST OFFICE BOX 655303

1.4 V

0.7 V

0 V

“L”

0 V

Vref + 0.7 V

1.5 V

VCC

0 V

OSCILLATOR

WAVEFORM (see Note A)

DEAD-TIME

INPUT VOLTAGE

ERROR AMP. OUTPUT

PWM COMP. OUTPUT

OUTPUT PIN WAVEFORM

REGULATED OUTPUT

VOLTAGE (see Note B)

SCP PIN WAVEFORM

SCP COMP. OUTPUT

POWER SUPPLY

VOLTAGE

“H”

“L”

“H”

“L”

“H”

2.7 V

VA

VA

VA

DEAD-TIME 100%

tpe

Protection Enable Time, tpe = 477×103 Cpe (sec)

Figure 1. Timing Diagram (CH-1/CH-2)

0 V

Vref + 0.7 V

1.5 V

VCC

0 V

REGULATED OUTPUT

VOLTAGE (see Note B)

SCP PIN WAVEFORM

SCP COMP. OUTPUT

POWER SUPPLY

VOLTAGE

“L”

“H”

2.7 V

VA

VA

VA

tpe

Protection Enable Time, tpe = 477×103 Cpe (sec)

1.4 V

0.7 V

“L”

OSCILLATOR

WAVEFORM (see Note A)

ERROR AMP. OUTPUT

PWM COMP. OUTPUT

OUTPUT PIN WAVEFORM

“H”

“L”

“H”

DEAD-TIME 100%

Figure 2. Timing Diagram (CH-3/CH-4)

NOTES: A. Oscillator waveform of CH-1 and CH-2 is inverting output each other.

B. Va = input voltage of pin 29 (pin 24)