Datasheet
LT6109-1/LT6109-2
17
610912fa
where I
OVER
and I
UNDER
are the over and under currents
through the sense resistor which cause the comparators
to trip. I
MAX
is the maximum current through the sense
resistor.
Depending on the desired maximum amplifier output volt-
age (V
MAX
) the three output resistors, R1, R2 and R3, can
be configured in two ways. If:
V
MAX
>
400mV
I
OVER
+
400mV –I
UNDER
R1
( )
I
UNDER
I
MAX
then use the configuration shown in Figure 3. The desired
trip points and full-scale analog output voltage for the
circuit in Figure 3 can then be achieved using the follow-
ing equations:
APPLICATIONS INFORMATION
R1=
400mV
I
OVER
R2 =
400mV –I
UNDER
R1
( )
I
UNDER
R3 =
V
MAX
– I
MAX
R1+ R2
( )
I
MAX
If:
V
MAX
<
400mV
I
OVER
+
400mV –I
UNDER
R1
( )
I
UNDER
I
MAX
then use the configuration shown in Figure 11.
Figure 11. Typical Configuration with Alternative R
OUT
Configuration
OUTA
I
OUTA
–
+
–
+
V
+
C1
SENSEHI
INC2
INC1
R1
610912 F11
V
–
V
+
V
+
V
–
LT6109-1
SENSELO
EN/RST
OUTC2
V
RESET
R
C
V
PULLUP
LOAD
V
SUPPLY
V
SENSE
R
SENSE
UNDERCURRENT
FLAG
OVERCURRENT
FLAG
R
IN
+
–
OUTC14
3
2
1
5
–
+
V
–
V
–
V
+
I
SENSE
=
V
SENSE
R
SENSE
R
C
R2
6
7
8
9
10
R3
C
L
V
OUT
400mV
REFERENCE
C
LC
C
LC