Linear Technology LT3790 Demo Manual page 5

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DIFFERENCES BETWEEN LT3790 AND LT3791-1
The LT3790 is an improved version of the LT3791-1 and
is recommended for use in new designs. Some external
component values may change, but otherwise, the LT3790
is functionally equivalent to the LT3791-1. The differences
between the two products are:
1. The LT3790 has a 60mV (typical) full-scale V
current sense voltage, compared to 100mV (typical) for
the LT3791-1. This change allows lower power current
sense resistors to be used for most applications.
2. The LT3790 CTRL pin linear range is from 0V to 1.1V,
and has a turn-off threshold of 50mV(typical), compared
to a 200mV to 1.1V linear range and 175mV (typical)
DEMO MANUAL DC2123B
30
25
20
15
10
5
0
0 1 2 3 4 5
I (A)
OUT
Figure 5. V in Current Limit, V
OUT
turn-off threshold for the LT3791-1. These changes
make it easier to parallel two or more LT3790 ICs for
higher power levels.
3. The LT3790 C/10 pin pulls low when the V
is less than 1/10 full scale, compared to the LT3791-1,
where C/10 pulls low when both V
(ISP-ISN)
1/10 full scale and V
Since the C/10 pin is used to allow DCM mode for some
applications, this change ensures that negative current
does not occur at light loads for a broader range of
applications.
6 7 8
dc2009a F05
= 24V
IN
is greater than 1.15V(typical).
FB
voltage
(ISP-ISN)
is less than
(ISP-ISN)
dc2123bfa
5