LT3751EUFD#PBF Linear Technology, LT3751EUFD#PBF Datasheet - Page 25

• Manufacturer Part Number: LT3751EUFD#PBF
• Description: IC CAPACITOR CHRG 20-QFN
• Manufacturer: Linear Technology

Specifications of LT3751EUFD#PBF

• Applications: Photoflash Capacitor Charger
• Current - Supply: 5.5mA
• Voltage - Supply: 4.75 V ~ 24 V
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 20-QFN
• Primary Input Voltage: 24V
• No. Of Outputs: 1
• No. Of Pins: 20
• Operating Temperature Range: -40°C To +125°C
• Msl: MSL 1 - Unlimited
• Supply Voltage Range: 4.75V To 24V
• Termination Type: SMD
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

TYPICAL APPLICATIONS
12V TO 24V
12V TO 24V
85
80
75
70
65
50
Effi ciency
V
TRANS
V
CC
150
+
V
OUTPUT VOLTAGE (V)
TRANS
C1
10μF
V
C3
1000μF
CC
DANGER HIGH VOLTAGE! OPERATION BY HIGH VOLTAGE TRAINED PERSONNEL ONLY
250
OFF ON
R10, 100k
R11, 100k
R1, 191k
R2, 475k
R3, 191k
R4, 475k
350
V
V
TRANS
TRANS
CHARGE
CLAMP
V
DONE
FAULT
UVLO1
OVLO1
UVLO2
OVLO2
GND RBG
CC
450
= 12V
= 24V
3751 TA02b
RV
LT3751
TRANS
R9
787Ω
R6
40.2k
HVGATE
LVGATE
RV
RDCM
3751 TA02
CSN
CSP
OUT
FB
1200
800
400
0
R7, 18.2k
R8, 40.2k
200
Output Capacitor Charge Times
C2
10μF
3
V
CC
V
V
V
V
V
V
V
V
OUT
OUT
OUT
OUT
OUT
TRANS
OUT
TRANS
400
42A Capacitor Charger
OUTPUT CAPACITANCE (μF)
= 500V, V
= 500V, V
= 300V, V
= 300V, V
= 100V,
= 100V,
= 24V
= 12V
600
•
T1**
1:10
M1, M2*
R5
2.5mΩ
TRANS
TRANS
TRANS
TRANS
•
800
= 24V
= 12V
= 24V
= 12V
D1
4.7nF
Y-RATED
C1: 25V X5R OR X7R CERAMIC CAPACITOR
C2: 25V X5R OR X7R CERAMIC CAPACITOR
C3: 25V ELECTROLYTIC
C4: HITACHI FX22L122Y 1200μF , 550V ELECTROLYTIC
OR: CORNELL DUBILIER DCMC192T550CE2B 1900μF , 550V ELECTROLYTIC
D1, D2: VISHAY GURB5H60 600V, 5A ULTRAFAST RECTIFIER
M1, M2: 2 PARALLEL VISHAY SUP33N20-60P 200V, 33A NMOS
R1 THRU R4, R6 THRU R11: USE 1% 0805 RESISTORS
R5: USE 2 PARALLEL 5mΩ IRC LR SERIES 2512 RESISTORS
T1: COILCRAFT GA3460-BL 50A SURACE MOUNT TRANSFORMER
FOR ANY V
50V AND 500V SELECT R9 ACCORDING TO:
1000
D2***
R
3751 TA02c
9 0 98
+
=
1200
OUT
.
C4
1200μF
• •
VOLTAGE BETWEEN
V
500V
N
OUT
CURRENT
AVERAGE
100V/DIV
⎛
⎜
⎝
5A/DIV
V
INPUT
OUT
V
40 2
OUT
+
*** D2 MAY BE OMITTED FOR OUTPUT
. Ω
** THERMAL DISSIPATION OF T1 WILL LIMIT
V
k
* M1, M2 REQUIRES PROPER
Charging Waveform
DIODE
V
V
C4 = 1200μF
HEATSINK/THERMAL DISSIPATION
TO MEET MANUFACTURER’S SPECIFICATIONS
THE CHARGE/DISCHARGE DUTY CYCLE OF C4
VOLTAGE OPERATION BELOW 300V
OUT
TRANS
⎞
⎟
⎠
= 500V
= 24V
100ms/DIV
LT3751
3751 TA02d
25
3751fb