21/25
L6995
POWER SECTION
Notes: 1. N.M.=Not M ounted
2. Th e demoboard wit h thi s component list is set to give: V
OUT
= 1.8V, F
SW
= 25 0kHz w i t h an i nput voltage around V
IN
= 20V an d
wi th the int egrator feature.
3. Th e di ode eff i ciency im pact is ve ry low; it is no t a necessa ry com ponent.
4. All capacitors are in tended c eramic t ype othe rwi se spec i f i ed.
3.11.1Efficiency
V
in
= 20V V
out
= 1.8V F
sw
= 270kHz
Figure 18. Efficiency vs ou tput current
Part name Value Dimension Notes
C10 100nF 0603
C11 100nF 0603
DIODE
D1 BAR18
INPUT CAPACITORS
C7, C13 10µF C34Y5U1E106ZTE12 TOKIN
OUTPUT CAPACITORS
C14, C15 33 0µF EE FUE0 D331 R
PANAS ONIC
INDUC TOR
L1 2.7µH DO3316P -272 HC
COILC RAFT
2.2µH ET QP6H 2R2G F
PANAS ONIC
3.3µH DQ7545
COEV
POWER MOS
Q1,Q2 STS8DNF3LL STMicroelectronics Double mos in sigle package
DIODE
D2 STPS3L40U STMicroelectronics
3
30
40
50
60
70
80
90
0,0 0,5 1 ,0 1 ,5 2, 0 2,5 3,0 3,5 4,0 4, 5 5,0 5,5 6,0
Cu rrent [A]
Eff [ %]
Vin=20V Vout=1.8V Fsw=270Khz PWM Vin=20V V out=1.8V Fs w =270Khz PFM
