PARTS SHIPPED to LA Tech (I left similar components and quantities with UAH):
Part Name
Molex - 4 position Connector
Housing (1.5 mm pitch w/ramp)
1x1 - 0.1”Crimp Connector Housing
26AWG wires with female
terminals on one end and male
terminals on the other end
#4 Lock washers
Pico-SPOX™ Crimp Terminal,
Tin(Sn), 24-30 AWG
Black heat sink
Female Connector Socket (2 pin)
D2 – Pak heat sink
Part Number
Digi-Key: WM2088-ND
Molex: 0874390400
Pololu: 1900
Pololu: 1801
QTY
6
(+2 extra)
8 extra
8 extra
McMaster-Carr: like 98437A102
Digi-Key: WM1112-ND
Molex: 87421-0000-C
Like this link
Digi-Key: ED23064-ND
Mill-Max: 310-93-164-41-105000
Digi-Key: HS338Ct-ND
Aavid Thermalloy: 573300D00010G
17 extra
24
(+8 extra)
1
6 extra
4
NOT INCLUDED:
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
Prop Plug
Discrete sensing resistors for Full H-Bridges (L298 - page 1,3, and 7)
Molex crimping tool, to connect 24 thru 30 AWG gauge wire to Molex - 4 position Connector Housing
o It’s possible to solder wire to the Pico-SPOX™ Crimp Terminals (WM1112-ND) but tool is easier.
Full safety margin for:
o Connector wire at J7 (See figure 2a)
 The 26 AWG wire @ J7 isn’t thick enough to handle both Full H-Bridges on at max
current, since each can draw 2.0 Amps and max rating of the 26 AWG wire is 2.2 Amps
for chassis wiring like we have. My recommendation, buy new 0.1 inch pitch
connector, and use 21 AWG or lower gauge wiring.
 See http://www.powerstream.com/Wire_Size.htm
o + Power bus line connected to J7
 Cooper trace is 0.050 inches, which can handle 2.0 Amps. Thus both outputs channels
on U2 & U1 components can each be used at 50% duty cycle or one output on each
component can be used at 100% duty cycle. Watch for overheating on cooper trace
between J7 and C1. Heat sink may need to be attached.
Complete testing of U3 component (ADC0834) in order to speed delivery.
o Pins 1 and 9 may need to be shorted together.
o Source code folder to use this ADC called CD_ADC0834 is included in the zip file this document
came with.
IMPORTANT
Schottky flywheel diodes (D1 – D6) need to be removed for board to work correctly!!!!!
Possible short between U2 Full H-Bridges pins 13 -15 and ground eliminated with Kapton tape; however, that
may reduce heat transfer by as much as 50%. Thus watch for overheating on this IC and use only channel A
output channel if possible.
Figure 1 – Segment controller schematic of microcontroller (U0), Full H-Bridges (U1 & U2), ADC (U3), EEPROM (U4), Voltage Regulators
(U5 & U6), 0.1” pin header (J1 – J9), Linear Actuators (A1 – A3), and Schottky flywheel diodes (D1 – D6)
NOT SHOWN: flywheel diodes D7 & D8 and connections between UO pins 13 thru 15 and U2 pins 15 thru 13 respectively
Figure 2a - Top layer copper traces of the four layer segment
Figure 2b - Bottom layer copper traces of the four layer
controller PCB. Dimensions 2.5” x 1.85”
segment controller PCB. Dimensions 2.5” x 1.85”
14
11
8
7
13
4
6
0
15
13
5
3
13
4
14
14
Figure 3b – Zoomed in photo of top side of PCB
Figure 3a – Top side of PCB
14
14
12
9
2
1
16
12
10
14
14
Figure 3d – Bottom side of PCB
Figure 3c – Isometric view of PCB
Circuit labels:
0
3
6
9
12
15
Parallax microprocessor (P8X32A-Q44)
Green & Red LED (LNJ121W84RA)
10 general I/O pins
Table 1
1
4
7
5 MHz Crystal (??????)
Full H-Bridge (L298)
2 five volt outputs
Can source or sink 40 mA, from 0 to 3.3 volts
Can source a total of 0.5 Amps
0.5 amp & 3.3V voltage regulator
(LM2937 – 3.3)
Schottky flywheel diodes
(Should be removed for board to work)
Reset switch (ADTS3)
10 0.5 amp & 5.0V voltage regulator
13
16
(LM2937 – 5.0)
Molex Wire-to-board connectors
(0874380442)
Access to parallax chip pins P8
and P9 via surface mount pads
2
5
8
32KB EEPROM (24LC 256)
Four channel ADC (ADC0834)
4 Low power ground connections
Low power means < 5V and 100 mA
11 Power source input pins:
PWR & GND
Max DC voltage & current = 12V & 2A
14 Heat sink connection areas and
mounting bracket holes
*Part numbers in parentheses
INPUT/OUTPUT:
 Propeller chip is programmed by attaching Prop Plug to J5. With Prop Plug’s VSS pin going to J5 GND.
 P0 through P7 can be accessed @ J6. While P8 & P9 can be accessed @ J5 after chips been programmed
o See pin layout in figure 4
Figure 4
¥ The 8 – pin Pololu connector is hard to get off & on of J6, so try not to remove it too much.
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Green LED is connected to P11 and Red LED is connected to P12.
P30, P31, and ground be accessed @ J5 after programming with Prop Plug completes (See figure ??)
ADC channels and four Full H-Bridges outputs can be accessed at BW2 and BW1 & BW3 respectively.
Extra pins P8 & P9 can be access via surface mount pads above 5.0 V voltage regulator (U5)
o See Figures 3d & 2b
POWER:
 Parallax Propeller chip (U0) can be reset with SW1 button or in software by setting P10 low.
 You can determine reset state of U0 by checking logic level at U0’s RESn pin.
o Zero – Chip is in the middle of resetting.
o One – Chip is done resetting.
 Max current that can be withdrawn from J8 (+5V) output is 500 mA (The limit of 5.0 V regulator)
 Max current that can be tapped off +3.3V output is 100 mA (The limit of 3.3 V regulator minus 400 mA for U0)
 Heat sink connection paths important for long terming running of board (longer than 15 minutes)
o See figure3d
 Discrete sensing resistors connected @ jumpers J1 thru J4 control current to output channels of U1 & U2.
o I recommend shorting jumper pins of each jumper together at first to test actuators. Then use
a small resistor value (most likely less the 5 ohms) that closely matches internal resistance of
actuator, if current limiting is really needed.
o See L298 - page 1,3, and 7 are more details
Source Code:
 Wormbot_Main_Driver.spin – Blaze written code to test Full H-Bridge , LED, and general I/O functions. Can
be used as starting control for control of robot. ADC functionis not complete (See CD_ADC0834 .zip)
 CD_ADC0834 .zip – Parallax code to control ADC (U3 component) on board