MP5010B – 3V-18V, 1A-5A PROGRAMMABLE CURRENT LIMIT SWITCH
APPLICATION INFORMATION
Current Limit
The current limit is a function of the external
current-limit resistor. Table 2 and Table 3 list
examples of current values as a function of the
resistor value for both Kelvin current sensing and
direct current sensing.
R
LIMIT
(Ω)
Trip Current (A)
Hold Current (A)
10
2.31
1.45
22
2.18
1.10
Rise Time
The rise time is a function of the capacitor (C
dv/dt
)
on the dv/dt pin. Table 4 lists typical rise times as
a function of capacitance.
Table 2: Current Limit vs. Current Limit Resistor (V
CC
=5V, Kelvin Current Sensing)
51
2.05
0.71
75
2.00
0.56
100
1.99
0.47
Table 3: Current Limit vs. Current Limit Resistor (V
CC
=5V, Direct Current Sensing)
R
LIMIT
(Ω)
Trip Current (A)
Hold Current (A)
22
4.31
2.79
51
3.10
1.29
75
2.69
0.91
100
2.52
2.43
220
2.31
0.40
Table 4: Rise Time vs. C
dv/dt
C
dv/dt
Rise Time
(typ., ms)
330pF
1.1
1nF
3
3.3nF
9.4
6.8nF
19.2
*
Notes:
Rise Time = K
RT
*(50pF+C
dv/dt
), K
RT
=2.8E6
The “rise time” is measured by from 10% to 90%
of output voltage.
U
Input
Output
90%
Enable
10%
Rise Time
t
Figure 2—Rise Time
MP5010B Rev. 1.0
www.MonolithicPower.com
4/3/2013
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
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