LT1162 LINER [Linear Technology], LT1162 Datasheet - Page 11

• Manufacturer Part Number: LT1162
• Description: Half-/Full-Bridge N-Channel Power MOSFET Drivers
• Manufacturer: LINER [Linear Technology]

APPLICATIONS
Motor Drive Applications
In applications where rotation is always in the same
direction, a single LT1160 controlling a half-bridge can be
used to drive a DC motor. One end of the motor may be
connected either to supply or to ground as seen on Figure
3. A motor in this configuration is controlled by its inputs
which give three alternatives: run, free running stop (coast-
ing) and fast stop (“plugging” braking, with the motor
shorted by one of the MOSFETs).
To drive a DC motor in both directions the LT1162 can be
used to drive an H-bridge output stage. In this configura-
tion the motor can be made to run clockwise, counter-
clockwise, stop rapidly (“plugging” braking) or free run
(coast) to a stop. A very rapid stop may be achieved by
reversing the current, though this requires more careful
design to stop the motor dead. In practice a closed-loop
control system with tachometric feedback is usually
necessary.
U
REF PWM
INFORMATION
Figure 2. Adding Synchronous Switching to a Step-Down Switching Regulator
U
OUT A
OUT A
12V
W
SV
PV
IN TOP
IN BOTTOM
+
+
LT1160
U
B GATE DR
T GATE DR
T GATE FB
T SOURCE
B GATE FB
BOOST
12V
R
The motor speed in these examples can be controlled by
switching the drivers with pulse width modulated square
waves. This approach is particularly suitable for micro-
computers/DSP control loops.
GS
Figure 3. Driving a Supply Referenced Motor
HV
IN TOP
IN BOTTOM
SV
PV
+
+
LT1160
+
B GATE DR
T GATE DR
T SOURCE
B GATE FB
T GATE FB
R
BOOST
PGND
SENSE
+
LT1160/LT1162
1160 F02
V
OUT
+
11
1160 F03
HV