DSP56156 Motorola Inc, DSP56156 Datasheet - Page 66

• Manufacturer Part Number: DSP56156
• Description: 16-bit Digital Signal Processor
• Manufacturer: Motorola Inc

capacitor lead. The use of at least a four lay-
er board is recommended, employing two
inner layers as V
output pins on this DSP have fast rise and
fall times. Printed Circuit Board (PCB)
trace length should be minimized in order
to minimize undershoot and reflections
caused by these fast output switching
times. This recommendation particularly
applies to the address and data buses as
well as the PS/DS, BS, RD, WR, R/W, inter-
rupt, and HEN pins. Maximum PCB trace
lengths on the order of 6" are recommended.
Capacitance calculations should consider all
MOTOROLA
Address Bus Buffers
Data Bus Buffers
Bus Control Buffers
Codec
Digital Peripherals
Internal logic
Phase-Locked Loop (PLL)
CC
Circuitry
and GND planes. All
Freescale Semiconductor, Inc.
Table 26 Power and Ground Connections
For More Information On This Product,
Go to: www.freescale.com
DSP56156 Data Sheet
Signal
Name
V
V
V
V
V
V
V
V
V
V
V
CC1
CC2
CC3
CC4
CC5
CCA
CC6
CC7
CCQ0
CCQ1
CCS
Power
device loads as well as parasitic capacitanc-
es due to PCB traces. Attention to proper
PCB layout and bypassing becomes espe-
cially critical in systems with higher capac-
itive loads because these loads create
higher transient currents in the V
GND circuits.
many signals and should be kept away
from analog power and ground traces as
well as any analog signals. See Figure 44 for
more details.
Clock signals should not be run across
Pin #
103
92
15
36
23
59
76
33
96
50
4
Signal
Name
GND0
GND1
GND2
GND3
GND4
GND5
GND6
GND7
GND8
GNDA
GND9
GND10
GNDQ0
GNDQ1
GNDS
Ground
Pin #
101
108
104
89
95
12
18
38
26
53
73
47
48
1
7
Power, Ground, and Noise
CC
Design Considerations
and
61