TL494PULSE-WIDTH-MODULATION CONTROL CIRCUITS

SLVS074D JANUARY 1983 REVISED MAY 2002

6 POST OFFICE BOX 655303 DALLAS, TEXAS 75265

PARAMETER MEASUREMENT INFORMATION

TestInputs

DTC

FEEDBACK

RT

CT

GND50 k

12 k

0.01 F

VCC

REFOUTPUTCTRL

E2

C2

E1

C1 Output 1

Output 2

150 2 W

150 2 W

VCC = 15 V

TEST CIRCUIT

1IN+

VCC

VCC

0 V

0 V

Voltageat C1

Voltageat C2

Voltageat CT

DTC

FEEDBACK

0 V

0.7 V

0% MAX0%

Threshold Voltage

Threshold Voltage

VOLTAGE WAVEFORMS

Duty Cycle

ErrorAmplifiers

7

14

12

8

9

11

10

4

3

6

5

121615

13

1IN

2IN2IN+

Figure 1. Operational Test Circuit and Waveforms

TL494PULSE-WIDTH-MODULATION CONTROL CIRCUITS

SLVS074D JANUARY 1983 REVISED MAY 2002

7POST OFFICE BOX 655303 DALLAS, TEXAS 75265

PARAMETER MEASUREMENT INFORMATION

+

+

VI

Vref

FEEDBACK

Amplifier Under Test

Other Amplifier

Figure 2. Amplifier Characteristics

OutputEach OutputCircuit

68 2 W

15 V

CL = 15 pF(See Note A)

90%

10%

90%

10%

tf tr

TEST CIRCUIT OUTPUT VOLTAGE WAVEFORMNOTE A: CL includes probe and jig capacitance.

Figure 3. Common-Emitter Configuration

Output

Each OutputCircuit

68 2 W

15 V

CL = 15 pF(See Note A)

90%

10%

90%

10%

tftr

TEST CIRCUIT OUTPUT VOLTAGE WAVEFORM

NOTE A: CL includes probe and jig capacitance.

Figure 4. Emitter-Follower Configuration