Datasheet

LT6109-1/LT6109-2
9
610912fa
PIN FUNCTIONS
INC1 (Pin 6): This is the inverting input of comparator 1.
The second input of this comparator is internally connected
to the 400mV reference.
INC2 (Pin 7): This is the input of comparator 2. For the
LT6109-1 this is the noninverting input of comparator 2.
For the LT6109-2 this is the inverting input of compara-
tor2. The second input of each of these comparators is
internally connected to the 400mV reference.
OUTA (Pin 8): Current Output of the Sense Amplifier. This
pin will source a current that is equal to the sense voltage
divided by the external gain setting resistor, R
IN
.
V
+
(Pin 9): Positive Supply Pin. The V
+
pin can be con-
nected directly to either side of the sense resistor, R
SENSE
.
When V
+
is tied to the load end of the sense resistor, the
SENSEHI pin can go up to 0.2V above V
+
. Supply current
is drawn through this pin.
SENSEHI (Pin 10): Sense Amplifier Input. The internal
sense amplifier will drive SENSEHI to the same potential
as SENSELO. A resistor (typically R
IN
) tied from supply
to SENSEHI sets the output current, I
OUT
= V
SENSE
/R
IN
,
where V
SENSE
is the voltage developed across R
SENSE
.
BLOCK DIAGRAMS
Figure 1. LT6109-1 Block Diagram (Comparators with Opposing Polarity)
100Ω
OUTA
+
+
9
10
1
8
INC2
7
INC1
610912 F01
6
V
+
V
V
V
V
V
+
3k
V
+
3k
SENSEHI
LT6109-1
SENSELO
200nA
RESET
UNDERCURRENT FLAG
OVERCURRENT FLAG
2
EN/RST
3
OUTC2
4
OUTC1
34V 6V
ENABLE AND
RESET TIMING
+
V
V
+
5
400mV
REFERENCE