Datasheet

LT1999-10/LT1999-20/
LT1999-50
21
1999fb
Typical applicaTions
Figure 9. Armature Current Monitor for DC Motor Applications
Figure 10. LT1999 Output Waveforms for the Circuit of Figure 9
1999 F09
V
BRIDGE
V
+IN
V
–IN
R
SENSE
0.025Ω
10µF
PWM INPUT
DIRECTION
BRAKE INPUT
24V
5V
5V
GND
5V
PWM IN
OUTA
OUTB
C4
1000µF
24V MOTOR
H-BRIDGE
LT1999-20
4k
0.8k
160k
160k
2µA
0.8k
4k
SHDN
+
–
+
–
80k
V
+
V
+
V
+
V
+
0.1µF
0.1µF
8
7
6
V
SHDN
V
OUT
V
REF
2
3
1
4
V
+
5
TIME (20µs/DIV)
V
OUT
(2V/DIV)
V
+IN
(20V/DIV)
1999 F10
V
OUT
V
+IN
2.5V