LM5068MMX-3/NOPB National Semiconductor, LM5068MMX-3/NOPB Datasheet - Page 14
![IC CTLR HOT SWAP -48V 8-MSOP](/photos/6/57/65756/pkg_mua08a_sml.jpg)
LM5068MMX-3/NOPB
Manufacturer Part Number
LM5068MMX-3/NOPB
Description
IC CTLR HOT SWAP -48V 8-MSOP
Manufacturer
National Semiconductor
Type
Hot-Swap Controllerr
Datasheet
1.LM5068MM-3NOPB.pdf
(26 pages)
Specifications of LM5068MMX-3/NOPB
Applications
General Purpose
Internal Switch(s)
No
Voltage - Supply
-10 V ~ -90 V
Operating Temperature
-40°C ~ 105°C
Mounting Type
Surface Mount
Package / Case
8-TSSOP, 8-MSOP (0.118", 3.00mm Width)
Linear Misc Type
Negative Voltage
Family Name
LM5068-3
Package Type
MSOP
Operating Supply Voltage (min)
-10V
Operating Supply Voltage (max)
-90V
Operating Temperature (min)
-40C
Operating Temperature (max)
105C
Operating Temperature Classification
Industrial
Product Depth (mm)
3mm
Product Height (mm)
0.86mm
Product Length (mm)
3mm
Mounting
Surface Mount
Pin Count
8
For Use With
LM5068EVAL - EVALUATION BOARD FOR LM5068
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Other names
LM5068MMX-3
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
LM5068MMX-3/NOPB
Manufacturer:
TI
Quantity:
25
www.national.com
Sense Resistor (R
Capacitor (C
Mosfet (Q1) Selection
Applying Equation (5) and Equation (7) to Equation (2) gives
the TIMER capacitor value of:
Finally, the SOA curves of a prospective MOSFET are
checked using V
from equation Equation (6) and time of the current flow from
Equation (2).
Example: For: I
C
To account for tolerances of R
TIMER threshold voltage, the computed C
increased, for this example 50% was selected, therefore:
C
The maximum active current limiting value and duration are:
The N-channel MOSFET selection for use with the LM5068
controller in this example must be capable of sustaining
L
T
=100µF,
= 300nF • 1.5 = 450nF
L
IN (MAX)
=1A, V
T
) and N-Channel
, and I
DD
= 48V, V
SHORT-CIRCUIT (MAX)
s
), Timer
S
, C
L
DD (MAX)
, TIMER current and
(Continued)
T
value should be
= 100V and
calculated
(10)
(8)
(9)
14
V
condition. A device that meets the established criteria is the
Vishay - 5UB85N10-10.
External Sense Resistor
Precise current measurement depends on the accuracy of
the sense resistor (R
nection and close location of R
considered. Figure 4 demonstrates PCB layout for the Kelvin
sensing.
The R
is the normal maximum operating load.
DD
=100V and I
S
power rating should be greater than I
FIGURE 4. Sense Resistor Connections
(MAX)
S
=3A for 7.5ms in the worst case fault
). For the optimal results, Kelvin con-
S
to the LM5068 should be
2
L
*
R, where I
20078623
L