MC68HC711PH8 Motorola, MC68HC711PH8 Datasheet - Page 28

• Manufacturer Part Number: MC68HC711PH8
• Description: High-density Complementary Metal Oxide Semiconductor (HCMOS) Microcomputer Unit
• Manufacturer: Motorola

2
2.1
Power is supplied to the microcontroller via these pins. VDD is the positive supply and VSS is
ground. The MCU operates from a single 5V (nominal) power supply.
It is in the nature of CMOS designs that very fast signal transitions occur on the MCU pins. These short
rise and fall times place very high short-duration current demands on the power supply. To prevent
noise problems, special care must be taken to provide good power supply bypassing at the MCU.
Bypass capacitors should have good high-frequency characteristics and be as close to the MCU as
possible. Bypassing requirements vary, depending on how heavily the MCU pins are loaded.
The MC68HC11PH8 MCU has five VDD pins and five VSS pins. One pair of these pins is reserved for
supplying power to the analog-to-digital converter (VDD AD, VSS AD); two pairs are used for the
internal logic (VDD, VSS); the remaining two pairs supply power for the port logic on either half of the
chip (VDDL, VSSL and VDDR, VSSR). This arrangement minimizes the injection of noise into the
digital circuitry on the chip.
MOTOROLA
2-2
MODB/VSTBY
VDD and VSS
LCDBP/PG6
VPPE/XIRQ
MOSI2/PG3
MISO2/PG2
SCK2/PG4
TXD2/PG1
PW1/PH0
PW2/PH1
PW3/PH2
PW4/PH3
R/W/PG7
SS2/PG5
VDDL
VSSL
PH4
PH5
PH6
PH7
NC
NC
NC
NC
NC
NC
NC
NC
NC
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
Figure 2-2 112-pin TQFP pinout
PIN DESCRIPTIONS
84
83
82
81
80
79
78
77
76
75
74
73
72
71
70
69
68
67
66
65
64
63
62
61
60
59
58
57
VDDSYN
VDDR
VSSR
NC
PD2/MISO
PD1/TXD
PD0RXD
MODA/LIR
RESET
XFC
NC
NC
NC
EXTAL
XTAL
E
4XOUT
PC7/D7
PC6/D6
PC5/D5
PC4/D4
PC3/D3
PC2/D2
PC1/D1
PC0/D0
IRQ
NC
NC
MC68HC11PH8
TPG