Datasheet

9
LT1620/LT1621
APPLICATIONS INFORMATION
WUU
U
Figure 5a. Typical Setpoint Voltage (V
PROG
) Changes Slightly
Depending Upon the Amount of Current Sinked by the I
OUT
Pin
IN
+
– IN
–
(V
ID
) INPUT (mV)
0
V
PROG
OFFSET (mV)
20
10
0
–10
–20
–30
–40
60 100
LT1620/21 • F05b
20 40
80 120 140
V
CC
= 5V
V
CM
= 16.8V
I
OUT
= 130µA
Figure 5b. Typical Setpoint Voltage (V
PROG
) Changes Slightly
Depending Upon the Programmed Differential Input Voltage (V
ID
)
I
OUT
SINK CURRENT (µA)
0
V
PROG
OFFSET (mV)
150
250
LT1620/21 • F05a
50 100 200
40
30
20
10
0
–10
–20
–30
–40
V
CC
= 5V
V
ID
= 80mV
V
CM
= 16.8V
Figure 5e. Typical Setpoint Voltages for V
PROG
and V
PROG2
Change Slightly Depending Upon the Supply Voltage (V
CC
)
V
CC
(V)
4.50
PROGRAMMING OFFSET (mV)
0
5
5.50
LT1620/21 • F05e
–5
–10
4.75
5.00
5.25
10
V
PROG
V
PROG2
V
ID
= 80mV
V
CM
= 16.8mV
I
OUT
= 130µA
IN
+
– IN
–
(V
ID
) INPUT (mV)
0
V
PROG2
OFFSET (mV)
40
20
0
–20
–40
–60
–80
60 100
LT1620/21 • F05c
20 40
80 120 140
V
CC
= 5V
V
CM
= 16.8V
I
OUT
= 130µA
Figure 5c. Typical Comparator Threshold Voltage (V
PROG2
)
Changes Slightly Depending Upon the Programmed Differential
Input Voltage (V
ID
)
Figure 5d. Sense Amplifier Input Offset Tolerence Degrades for
Input Common Mode Voltage (V
CM
) Below (V
CC
– 0.5V). This
Affects the SENSE, AVG and AVG2 Amplifier Outputs
IN
+
, IN
–
COMMON MODE VOLTAGE (V
CM
) (V)
0

±8
±10
±12
35
LT1620/21 • F05d
±6
±4
12
436
±2
0
ADDITIONAL INPUT REFERRED OFFSET (mV)
±14

V
CC
= 5V
V
ID
= 80mV
I
OUT
= 130µA