Ic851(Tl1451) Is A 2-Way Pwm Control Ic - BenQ G2420HD Product Service Manual

IC851(TL1451) is a 2-way PWM control IC.

C851/R851 determine the frequency of PWM.
Pin 1IN+/1IN- and 2IN+/2IN- are the inputs of the error amplifiers. 1IN+/2IN+ are used as the
feedback pins for DC-DC circuit.
1DTC/2DTC are used for determining the threshold states of dead time control.
C854, C855, C857, C858, R855 and R873 are used for gain/phase compensation.
The timing diagram of TL1451 is shown as following:
P11
C853
1U M
R856
330K
R853
10K F
C855
0.01U K
R854
10K F
R855
47K
C854
220P K
IC851
C852 TL1451ACN
0.1U K
C851 R851
10K F
470P K C857
220P K
R873
47K
R857
C858
C856 10K F
0.01U K
1U M
R858 R859
330K
10K F
- 65 -
V-INVERTER
F851
32V 2A
R863
330
C859
1U M
P13