FlexDrive Dual Motor H-Bridge Board No
longer in production, sorry....
Assembled FlexDrive Circuit Board
(click for larger image)
Demonstration Robot Using FlexDrive
(click for larger image)
- up to 1.1 A per brushed DC motor at up to 36 volts
- flexible control of motor speed, direction, and braking
- can be controlled with as little as 1 I/O line for simple on/off control,
or use 3 I/Os per motor for complete control!
- small size for small but powerful robots
View Board Layout
Rev 1.00 of the prototype board requires a small jumper wire connecting
between R1 nearest pin 2 of U2, and pin 2 of U2 itself. Without this wire,
R1 does not pull down the PWM input for Motor 1, so a floating or disconnected
PWM input might result in unwanted motor activity.
Bill of Materials
Count Component Type Module Type Component Reference
----- ---------------- --------------- ---------------------
6 47K RC05 R1 though R6
1 470uF 40v CK15-S C1
1 0.1uF CM5-390 C2
1 SN754410 16DIP300 U1
2 74HCT00 14DIP300 U2 & U3
2 CONN02 2HDR-100 J1, J2, J5 & J6; JP1-JP3
1 CONN04 4HDR-100 J3 & J4
You can omit JP1-JP3 if you will always provide full control of the motors.
You can also omit R1-R6 if you will always connect all 6 control lines
to a microcontroller. However, they are still recommended due to the fact
that many microcontrollers float their I/O lines after reset until they
are explicitly set as outputs by your firmware. The resistors prevent
unwanted motor motion during the setup portion of your programs.
The value of C1 should be in the neighborhood of 470 uF, but the voltage
rating is flexible -- it all depends on what voltage your motors run at.
If you are using 12 volt motors, then a 25 volt radial electrolytic capacitor
would be fine.
The value of R1-R6 can be anything from 10K to 47K.
The value of U2 and U3 can also be 74HC00.
On rev 1.00 of the board, the holes for J1-J6 and JP1-JP3 are too small
for square pin headers. Round pin headers can be substituted, or you can
directly wire to the board without connectors. DO NOT drill out the holes
to make them bigger, as this will break the vias and potentially disconnect
some of the signals running though those holes.
Apply liberal solder to pins 4, 5, 12, and 13 of the SN754410 motor driver
chip, as this will help conduct heat away from the chip during operation.
Just be sure you don't create solder bridges to the adjacent pins!
Contact Pete Skeggs, plskeggs -at= noeticdesign d0t com, for support.