Datasheet

LT3751
29
3751fc
Isolated 282V Voltage Regulator
Typical applicaTions
DONE
FAULT
UVLO1
OVLO1
UVLO2
OVLO2
V
CC
CHARGE
CLAMP
RDCM
RV
OUT
V
IN
GND
OC
OPTO
V
CC
COMP
FB
HVGATE
LVGATE
FB
CSP
CSN
RV
TRANS
T1
D5
V
OUT
282V
225mA
V
TRANS
V
CC
3751 TA06a
LT3751
GND RBG
R3
210k
OFF ON
C3
22µF
×2
C1
100pF
C4
1µF
×2
C2
1µF
•
•
•
R7
475Ω
R4
105k
R5
210k
M2
R6
40mΩ
R18
1k
R8
2.49k
R17
221k
R16
249k
4.7nF
Y RATED
R1
49.9k
D1
D6
U2
LT4430
V
TRANS
V
CC
R10, 4.3M
R9, 2.7M
R2, 10Ω
ISOLATION BOUNDARY
Npb
Np Ns
Nsb
R12, 442k
R11, 84.5k
C1, C8: 16V COG CERAMIC
C2: 16V X5R OR X74 CERAMIC
C3: 350V ELECTROLYTIC
C4: 250V X5R OR X7R CERAMIC
C5, C6, C11, C12: 630V X5R OR X7R CERAMIC
C7: 350V ELECTROLYTIC
C9, C10: 25V X5R OR X7R CERAMIC
F1: 250V, 2A FUSE
R1: 2010 RESISTOR, 1%
R2, R3, R6, R16, R17: 1206 RESISTORS, 1%
R4, R5: TWO 1206 RESISTORS IN SERIES, 1%
R7 THRU R12, R15 THRU R20: 0805 RESISTORS, 1%
D1: 12V ZENER
D2: VISHAY MURS140
D3: VISHAY P6KE200A
D4: VISHAY MURS160
D5: STMICROELECTRONICS STTH112A
D6: VISHAY BAT54
D7: NXP SEMICONDUCTORS BAS516
M1: VISHAY IRF830
M2: STMICROELECTRONICS STB11NM60FD
T1: TDK SRW24LQ
(Np:Ns:Npb:Nsb = 1:2:0.08:0.08)
U1: NEC PS2801-1
U2: LINEAR TECHNOLOGY LT4430
TO
MICRO
V
TRANS
100V TO
200VDC
F1, 2A
C5
0.01µF
DANGER HIGH VOLTAGE! OPERATION BY HIGH VOLTAGE TRAINED PERSONNEL ONLY
D4
D3
M1
C9
3.3µF
C8
22nF
R19
3.16k
C10
0.47µF
•
R15
5.11Ω
D7
U1
D2
R20
274Ω
C6
0.1µF
+
+
C7
400µF
I
OUT
(mA)
0
–0.50
OUTPUT VOLTAGE ERROR (V)
0
50 100 200150
0.50
–0.25
0.25
250
3751 TA06b
100
EFFICIENCY (%)
100
95
90
85
80
75
70
180140
3751 TA06c
200160
INPUT VOLTAGE (V)
120
63W OUTPUT
48W OUTPUT
25W OUTPUT
20µs/DIV
3751 TA06d
I
PRIMARY
2A/DIV
V
DRAIN
100V/DIV
20µs/DIV
3751 TA06e
I
PRIMARY
2A/DIV
V
DRAIN
100V/DIV
Load Regulation Efficiency
Steady-State Operation with
225mA Load Current
Steady-State Operation with
7.1mA Load Current