AAT1140 Datasheet, PDF (17/19 Pages) Advanced Analogic Technologies – Fast Transient 600mA Step-Down Converter

SwitchReg^TM
AAT1140 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
AAT1140
Fast Transient 600mA Step-Down Converter
0.6² · (0.725Ω · 1.8V + 0.7Ω · [4.2V - 1.8V])
=
4.2V
+ (5ns · 1.4MHz · 0.6A + 70μA) · 4.2V = 118mW
T_J(MAX) = T_AMB + Θ_JA · P_LOSS = 85°C + (150°C/W) · 118mW = 102.7°C
1140.2007.12.1.1
www.analogictech.com
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