Other Parts Discussed in Thread: CSD18503Q5A
Tool/software: WEBENCH® Design Tools
Two designs using TPS40170 were simulated in Webench. The only difference is M1.
(1)
Design : 4561043/504 TPS40170RGYR
TPS40170RGYR 23.0V-25.0V to 12.00V @ 10.0A
M1 FDD8647L 89°C 1.107W Fairchild
(2)
Design : 4561043/504 TPS40170RGYR
TPS40170RGYR 23.0V-25.0V to 12.00V @ 10.0A
M1 CSD18503Q5A 105°C 1.204W Texas Instruments
Design 1 showed lower temp on M1 and power dissipation. However, CSD18503Q5A of design 2 has smaller Rdson and parasitic caps, the switching power loss is much higher.
Could anyone who knows how the power dissipation is calculated in Webench show me what causes this and the big temperature difference too?
Thank you.
