Computer Hardware User Manual

5
.0 Electrical and Mechanical Specifications
5.1 Electrical Specifications
Power Requirements
The Board uses the +5.0 VDC and GND lines from the USB connection.
This +5.0 VDC voltage is regulated down to +3.3 VDC for board power.
* NO EXTERNAL POWER SUPPLY INPUTS ARE REQUIRED *
+5.0 ± 0.1 V,
100 mA max.
5.2 Electrical Schematic
C20
0.1uF
R7 22
GND
GND
GND
GND
J3
USB-B
VBUS
1
D-
2
D+
3
GND
4
SHELL_1
5
SHELL_2
6
HEADER 1X
7
R4
1M
R1
0
C14
2.2uF
U2
CY7C64603-52NC
RESERVED_3
17
WAKEUP#
4
RESERVED_2
15
XCLKSEL
16
SCL
2
Vcc1
1
SDA
3
Vcc2
14
PA4/FWR#
10
PA5/FRD#
11
AVcc
5
PB0/T2
29
Gnd2
21
AGnd
8
XIN
6
XOUT
7
PB1/T2EX
30
PB2/RXD1
31
PB3/TXD1
32
PB4/INT4
33
PB5/INT5#
34
PB6/INT6
35
PB7/T2OUT
36
PC0/RxD0
43
PC1/TxD0
44
PC2/INT0#
45
PC3/INT1#
46
PC4/T0
48
PC5/T1
49
PC6/WR#
50
PC7/RD#
51
USBD+
25
USBD-
24
DISCON#
18
RESERVED_1
9
CLKOUT
12
RESET#
28
Vcc3
27
Gnd4
39
Gnd5
47
Gnd6
52
Vcc4
40
RDY2/AOE
42
CTL0/AINFLAG
41
CTL2/AOUTFLAG
37
XCLK
38
RESERVED_4
22
RESERVED_5
23
RESERVED_6
19
RESERVED_7
20
Gnd1
13
Gnd3
26
R15
1.5K
R13
1.5K
R14
1.5K
J4
HEADER 2x2
34
12
OS/A0
TCRIT
SDA SDA
SCL
+3.3 VDC
R2
1.5K
OS/A0
R9 22
TCRIT
SCL
SCL
SDA
U3
LM95235
VDD
1
D+
2
D-
3
GND
5
TCRIT#
4
OS/A0
6
SMBCLK
8
SMBDAT
7
OS/A0
Shunt to select the PCB
temperature diode.
R3
100k
GND
U1
LP2950CDT-3.3/TO252
IN
1
OUT
3
Y1
12 MHz
C18
0.1uF
R11 1.5K
R12
1M
C16
2.2uF
C15
0.1uF
Q1
MMBT3904/SOT
C17
0.1uF
+ 3.3 VDC
C1
0.1uF
C2
0.1uF
C3
0.1uF
C4
0.1uF
C5
0.1uF
U4
AT24C02-10SI-2.7
A0
1
A1
2
A2
3
Vss
4
Vcc
8
WP
7
SCL
6
SDA
5
+ 3.3 VDC
TP1
Use a 0.1 uF capacitor for each
Vcc pin of U2 and Reserved_6 pin.
+ 3.3 VDC
SDA
L1
C11
2.2uF
C12
0.1uF
C13
100 pF
TP2
TP3
TP4
C6
0.1uF
JP2
1
3
4
5
6
7
2
+ 3.3 VDC
C10
33pF
C9
33pF
1 uH
SCL
C19
100 pF
Schematic of the LM95235 Evaluation Board
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