AAT1141_08 Datasheet, PDF (17/21 Pages) Advanced Analogic Technologies – Fast Transient 600mA Step-Down Converter

SwitchReg^TM
AAT1141 Losses
P_TOTAL
=
I_O2
·
(R_DSON(HS)
·
V_O
+ R_DSON(LS)
V_IN
·
[V_IN
-V_O])
+ (t_sw · F · I_O + I_Q) · V_IN
PRODUCT DATASHEET
AAT1141
Fast Transient 600mA Step-Down Converter
0.6² · (0.35Ω · 1.8V + 0.3Ω · [4.2V - 1.8V])
=
4.2V
+ (5ns · 2MHz · 0.6A + 70μA) · 4.2V = 141mW
T_J(MAX) = T_AMB + Θ_JA · P_LOSS = 85°C + (150°C/W) · 141mW = 106.2°C
1141.2008.07.1.4
www.analogictech.com
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