LT4276
23
4276fa
For more information www.linear.com/LT4276
Typical applicaTions
25.5W (Type 2) PoE
+
Power Supply in Flyback Mode with 24V, 1A Output
Efficiency vs Load Current V
OUT
vs Load Current
+
V
OUT
24V AT 1A
–V
OUT
Q1
L2: COILCRAFT, DO1608C-103
L4: COILCRAFT, DO1608C-104
C2: 4.7µF, 50V, MURATA GRM31CR71H475M012
C5: 22µF, 35V, PANASONIC EEH-ZA1V220R
C7: 2.2µF, 100V, MURATA GRM32ER72A225KA35
T1: WÜRTH, 750314782 OR PCA EPC3603G
Q1-Q9: PSMN075-100MSE
T2: PCA EPA4271GE OR PULSE PE-68386NL
L2
10µH
L4
100µH
10µF
100V
10nF
100V
3.3k
24V
8.2Ω
10µF
10V
HSSRC
SWVCC FB31
PG
SG
T2P
ITHBROSCSFSTFFSDLYRCLASSGND
VPORT
LT4276B
HSGATE
ISEN
+
ISEN
–
V
IN
V
CC
C7
2.2µF
BSZ520N15NS3G
BAT54WS
BAT46WS
TO MICROPROCESSOR
4276 TA10
BSZ12DN20NS3
MMBT3906 MMBT3904
T1
150pF
0.1µF
6.49k
2.00kΩ
20Ω
100Ω
1/4W
120Ω||120Ω
1/4W
40mΩ
1/4W
15Ω
100Ω
1µF
10pF
0.47µF
107k5.23k
RLDCMP
24k35.7Ω
PTVS58VP1UTP
3.3nF
2.2nF
2KV
160k
10k
2.2nF
C2, C3
4.7µF
50V
C5
22µF
47pF
100V
47nF
100V
2.2nF
2kV
OPTO
BG36
LT4321
BG12TG12 TG36
TG78TG45BG45 BG78
OUTP
OUTN
EN
EN
IN12
T2
Q2 Q3
Q4 Q5
Q6 Q7
Q8 Q9
1
DATA
PAIRS
SPARE
PAIRS
2
3
6
4
5
7
8
IN36
IN45
IN78
47nF
100V
BAV19WS
••
•
•
•
FMMT723
LOAD CURRENT (A)
0.1
74
EFFICIENCY (%)
92
90
88
86
84
82
80
78
76
94
0.6 0.8 0.90.7 1.00.50.40.30.2
VPORT = 57V
VPORT = 50V
VPORT = 42.5V
LOAD CURRENT (A)
0.1
23.0
V
OUT
(V)
24.6
24.4
24.8
24.2
24.0
23.8
23.6
23.4
23.2
25.0
0.6 0.8 0.90.7 1.00.50.40.30.2
VPORT = 57V
VPORT = 50V
VPORT = 42.5V
