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