+VISO1
R1
+5V
+VCC
Motorola
DSP56004
R2
768Ω
WST
+
R3
301Ω
C1
REF1004-1.2
+150mV
SDO0
SDO1
SDO2
SCKT
SCKR
SDI0
4.7µF
To 3rd Motor
Leg
VREF
+
R4
43.2Ω
C2
4.7µF
C3
0.1µF
SDI1
To 2nd Motor
Leg
WSR
SCK/SCL
MISO/SDA
MOSI/HA0
HREQ
VREF +VCC
from
PWM
R5
200Ω
SS/HA2
CS
DOUT
C4
0.01µF
AC Motor
RSENSE
ADS7817
CLK
R6
200Ω
from
PWM
Opto-Couplers(1)
NOTE: (1) Suggested Opto-couplers are HCPL-2611 or
HCPL-7611. Inverters or buffers will be needed to drive
these devices. See the appropriate Hewlett-Packard data
sheet for more information.
1st Motor Leg
FIGURE 11. Motor Control Using an Isolated ADS7817.
®
ADS7817
15