AAT2513
Dual 600mA Step-Down
Converter with Synchronization
Design Example
Specifications
VO1
VO2
VIN
FS
2.5V @ 600mA (adjustable using 0.6V version), pulsed load ΔILOAD = 300mA
1.8V @ 600mA (adjustable using 0.6V version), pulsed load ΔILOAD = 300mA
2.7V to 4.2V (3.6V nominal)
1.7 MHz
TAMB 85°C
1.8V VO1 Output Inductor
µs
A
µs
A
(see table 1).
⋅ 1.8V = 2.2µH
L1 = 1.2
⋅ VO1 = 1.2
For Sumida CDRH2D11 2.2µH DCR = 98mΩ.
⎛
⎞
2.5V
⎠
4.2V
VO1
L ⋅ F
VO1
VIN
2.5
V
⎛
⎞
⎠
ΔI1 =
⋅ 1 -
⎝
=
⋅ 1 -
= 230mA
⎝
3.3µH ⋅ 1.7MHz
ΔI1
2
IPK1 = IO1
+
= 0.4A + 0.115A = 0.515A
2
PL1 = IO1 ⋅ DCR = 0.6A2 ⋅ 123mΩ = 44mW
2.5V VO2 Output Inductor
µs
A
µs
A
(see table 1).
⋅ 2.5V = 3.3µH
L1 = 1.2
⋅ VO1 = 1.2
For Sumida inductor CDRH2D11 3.3µH DCR = 123mΩ.
⎛
⎞
2.5V
⎠
4.2V
VO2
L ⋅ F
VO2
VIN
2.5
V
⎛
⎞
⎠
ΔI2 =
⋅ 1 -
⎝
=
⋅ 1 -
= 230mA
⎝
3.3µH ⋅ 1.7MHz
ΔI2
2
IPK2 = IO2
+
= 0.4A + 0.115A = 0.515A
2
PL2 = IO2 ⋅ DCR = 0.6A2 ⋅ 123mΩ = 44mW
16
2513.2007.04.1.1
ANALOGICTECH [ ADVANCED ANALOGIC TECHNOLOGIES ]
