S1K50000 Epson Electronics America, Inc., S1K50000 Datasheet - Page 99

• Manufacturer Part Number: S1K50000
• Description: Design Guide S1k50000 Series
• Manufacturer: Epson Electronics America, Inc.

Chapter 8: Pin Arrangement and Simultaneous Operation
94
(3) Separating input and output pins
(4) Critical signals
a) Place the clock and reset pins that require minimization of the influence of noise away from
b) Place the oscillator circuit’s input/output pins (OSCIN, OSCOUT) close to each other,
c) Place fast-operating input and output pins near the middle of one side of the chip (package)
d) If the delay time from any specific input pin to an output pin has a small margin in the
For pin arrangement, it is an important technique to separate input-pin groups from output-
pin groups, as this helps to reduce the influence of noise.
Input pins and bidirectional pins set for input are susceptible to noise. It is therefore
important that these pins do not coexist with output pins. To this end, place input pins,
output pins, and bidirectional pins so that they are separated from each other, with power-
supply pins placed between each group of pins to divide them.
When placing critical signals issued from such output pins as clock-input and fast-operating
output pins, observe the following precautions:
output pins and close to the power-supply pins (Figure 8-3).
separated from other pins by the power-supply pins (V
that are synchronous to the oscillator circuit near said pins (Figure 8-4).
(Figure 8-3).
customer specifications, place these input/output pins close to each other (Figure 8-3).
Figure 8-3 Example of the Placement of Critical Signal Pins – 1
Figure 8-2 Example of the Separation of Input and Output Pins
High speed input
Through output
Through input
V
V
DD
SS
Output pins
EPSON
Bid
output
pins
V
V
V
V
High speed
SS
DD
SS
DD
DD
, V
SS
). Do not place output pins
STANDARD CELL S1K50000 SERIES
DESIGN GUIDE