DSP56002RC40 Motorola Inc, DSP56002RC40 Datasheet - Page 103

• Manufacturer Part Number: DSP56002RC40
• Description: 24-BIT DIGITAL SIGNAL PROCESSOR
• Manufacturer: Motorola Inc

ELECTRICAL DESIGN CONSIDERATIONS
MOTOROLA
Use the following list of recommendations to assure correct DSP operation:
• Provide a low-impedance path from the board power supply to each V
• Use at least four 0.1 F bypass capacitors positioned as close as possible to the
• Ensure that capacitor leads and associated printed circuit traces that connect
• Use at least a four-layer Printed Circuit Board (PCB) with two inner layers for
• Because the DSP output signals have fast rise and fall times, PCB trace lengths
• Consider all device loads as well as parasitic capacitance due to PCB traces
• All inputs must be terminated (i.e., not allowed to float) using CMOS levels.
• Take special care to minimize noise levels on the PLL supply pins (both V
on the DSP, and from the board ground to each GND pin.
four sides of the package to connect the V
to the chip V
V
should be minimal. This recommendation particularly applies to the address
and data buses as well as the RD, WR, IRQA, IRQB, NMI, HEN, and HACK
pins.
when calculating capacitance. This is especially critical in systems with higher
capacitive loads that could create higher transient currents in the V
GND circuits.
and GND).
CC
and GND.
This device contains protective circuitry to
guard against damage due to high static
voltage or electrical fields. However, normal
precautions are advised to avoid application
of any voltages higher than maximum rated
voltages to this high-impedance circuit.
Reliability of operation is enhanced if unused
inputs are tied to an appropriate logic voltage
level (e.g., either GND or V
CC
and GND pins are less than 0.5 inch per capacitor lead.
DSP56002/D, Rev. 3
CAUTION
CC
).
CC
power source to GND.
Electrical Design Considerations
Design Considerations
CC
and
CC
CC
pin
4-3