S1K50000 Epson Electronics America, Inc., S1K50000 Datasheet - Page 38

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

Chapter 3 Types of Input/Output Buffers and
3.1 Types of Input/Output Buffers
3.1.1 Selecting Input/Output Buffers
STANDARD CELL S1K50000 SERIES
DESIGN GUIDE
The S1K50000 series is available for many and varied types of cells, which can be chosen
depending on the input interface level, the presence of Schmitt trigger inputs or pull-up/pull-
down resistors, the output drive capability, and the noise protection measures used. In
accordance with the descriptions below, choose the input/output buffers best suited for your
circuit. There are two methods for using the input/output buffers, one for single power supplies
(3.3 V or 2.0 V) and one for dual power supplies (5.0 V and 3.3 V, or 3.3 V and 2.0 V).
(1) Selecting input buffers
(2) Selecting output buffers
(3) Selecting bidirectional buffers
• Input/output interface level
a) Whether the required interface level is the CMOS or TTL level
b) Whether a Schmitt trigger input is needed (need for hysteresis characteristics)
c) Whether internal pull-up/pull-down resistors are required
a) The magnitude of the required output drive current (ILO and IOH)
b) Whether a noise protection measure is required
c) Whether a bus hold circuit is required
Refer to paragraphs (1) and (2) in the selection of bidirectional buffers.
1) For dual 5.0-V power supplies
2) For single power supplies and dual 3.3-V power supplies
Input level
Output level
Input level
Output level
TTL level, CMOS level, TTL Schmitt, CMOS Schmitt, PCI*
CMOS level, PCI*
LVTTL level, LVTTL Schmitt, PCI*
LVTTL level, PCI*
Usage Precautions
Chapter 3: Types of Input/Output Buffers and Usage Precautions
EPSON
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