Electronic Components Datasheet Search
  English  ▼

X  

Preview PDF HTML

LT4256-3IGN Datasheet(PDF) 10 Page - Linear Technology

Part # LT4256-3IGN
Description  Positive High Voltage Hot Swap Controller with Open-Circuit Detect
PDF  20 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
Manufacturer  LINER [Linear Technology]
Direct Link  http://www.linear.com
Logo LINER - Linear Technology

LT4256-3IGN Datasheet(HTML) 10 Page - Linear Technology

Back Button LT4256-3IGN Datasheet HTML 6Page - Linear Technology LT4256-3IGN Datasheet HTML 7Page - Linear Technology LT4256-3IGN Datasheet HTML 8Page - Linear Technology LT4256-3IGN Datasheet HTML 9Page - Linear Technology LT4256-3IGN Datasheet HTML 10Page - Linear Technology LT4256-3IGN Datasheet HTML 11Page - Linear Technology LT4256-3IGN Datasheet HTML 12Page - Linear Technology LT4256-3IGN Datasheet HTML 13Page - Linear Technology LT4256-3IGN Datasheet HTML 14Page - Linear Technology Next Button
Zoom Inzoom in Zoom Outzoom out
 10 / 20 page
background image
LT4256-3
10
42563f
APPLICATIO S I FOR ATIO
Hot Circuit Insertion
When circuit boards are inserted into a live backplane, the
supply bypass capacitors on the boards draw high peak
currents from the backplane power bus as they charge.
The transient currents can permanently damage the con-
nector pins and glitch the system supply, causing other
boards in the system to reset.
The LT4256-3 is designed to turn on a board’s supply
voltage in a controlled manner, allowing the board to be
safely inserted or removed from a live backplane. The
device also provides undervoltage and overvoltage as well
as overcurrent protection while a power good output
signal indicates when the output supply voltage is ready
with a high output.
Power-Up Sequence
An external N-channel MOSFET pass transistor (Q1) is
placed in the power path to control the power up of the
supply voltage (Figure 5). Resistor R5 provides current
detection and capacitor C1 controls the GATE slew rate.
Resistor R7 compensates the current control loop while
R6 prevents high frequency oscillations in Q1.
When the power pins first make contact, transistor Q1 is
held off. If the voltage on VCC is between the externally
programmed undervoltage and overvoltage thresholds,
VCC is above 9.8V and the voltage on TIMER is less than
4.65V (typ), transistor Q1 will be turned on (Figure 6). The
voltage on GATE rises with a slope equal to 30
µA/C1 and
the supply inrush current is set at:
IINRUSH = CL • 30µA/C1
(1)
where CL is the total load capacitance.
Figure 5. 1.6A, 48V Latchoff Application
Figure 6. Start-Up Waveforms
4256 F05
R5
0.025
Ω
LT4256-3
SENSE
13
12
10
5
7
8
16
15
1
2
4
9
VCC
GATE
VOUT
FB
PWRGD
RETRY
UV
OV
TIMER
GND
VIN
48V
GND
(SHORT PIN)
Q1
IRF530
D1
CMPZ5241BS
11V
R3
4.02k
R2
4.02k
R1
64.9k
R7
100
Ω
R9
4.02k
R6
10
Ω
R8
36.5k
PWRGD
VOUT
48V
1.6A
R4
51k
CL
C2
33nF
C3
0.01
µF
C1
10nF
OPEN
UV = 36V
OV = 73V
PWRGD = 40V
D2
SMAT70A
+
IOUT
500mA/DIV
VOUT
50V/DIV
5ms/DIV
4256 F06
PWRGD
50V/DIV
GATE
50V/DIV



Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20


Datasheet Download

Go To PDF Page


Link URL



Does ALLDATASHEET help your business so far?  [ DONATE ] 

About Alldatasheet   |   Advertisement   |   Contact us   |   Privacy Policy   |   Link to Datasheet    |   Link Exchange   |   Manufacturer List
All Rights Reserved©Alldatasheet.com


Mirror Sites
English : Alldatasheet.com  |   English : Alldatasheet.net  |   Chinese : Alldatasheetcn.com  |   German : Alldatasheetde.com  |   Japanese : Alldatasheet.jp
Russian : Alldatasheetru.com  |   Korean : Alldatasheet.co.kr  |   Spanish : Alldatasheet.es  |   French : Alldatasheet.fr  |   Italian : Alldatasheetit.com
Portuguese : Alldatasheetpt.com  |   Polish : Alldatasheet.pl  |   Vietnamese : Alldatasheet.vn
Indian : Alldatasheet.in  |   Mexican : Alldatasheet.com.mx  |   British : Alldatasheet.co.uk  |   New Zealand : Alldatasheet.co.nz
Family Site : ic2ic.com  |   icmetro.com