AAT1230/1230-1
18V 100mA Step-Up Converter
AAT1230/1230-1 Losses
DMAX
3
IRMS(ON) = IPEAK
·
0.834
3
= 1.270
= 0.527A
= 527mA
(1 - DMAX
3
)
IRMS(OFF) = IPEAK
·
0.166
3
= 1.270
= 0.298A
= 298mA
From datasheet curves, VIN = 3.6V, TCASE = 100°C, TSOPJW-12:
RDS(ON)L = 75mΩ, RDS(ON)IN = 220mΩ, θJA = 160°C/W.
2
2
PLOSS(RDSON) = IRMS(ON)
· (RDS(ON)L + RDS(ON)IN) + IRMS(OFF) · RDS(ON)IN
= 0.5272 (0.220 + 0.075) + 0.2982 · 0.075
= 0.082 + 0.007
= 89mW
TJ(MAX) = TAMB
+
θJA
· PLOSS(RDSON)
= 50 + 160 (0.089)
= 50 + 14.2
= 64.2°C
18
1230.2006.10.1.4