Datasheet

GLOSSARY
SYMBOLS, TERMS, AND DEFINITIONS
1–5
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INTRODUCTION
These symbols, terms, and definitions are in accordance with those currently agreed upon by the JEDEC Council
of the Electronic Industries Association (EIA) for use in the USA and by the International Electrotechnical Commission
(IEC) for international use.
operating conditions and characteristics (in sequence by letter symbols)
C
i
Input capacitance
The internal capacitance at an input of the device
C
io
Input/output capacitance
Input-to-output internal capacitance; transcapacitance
C
o
Output capacitance
The internal capacitance at an output of the device
C
pd
Power dissipation capacitance
Used to determine the no-load dynamic power dissipation per logic function (see individual circuit pages):
P
D
= C
pd
V
CC
2
f + I
CC
V
CC
f
max
Maximum clock frequency
The highest rate at which the clock input of a bistable circuit can be driven through its required sequence
while maintaining stable transitions of logic level at the output with input conditions established that
should cause changes of output logic level in accordance with the specification
I
CC
Supply current
The current into* the V
CC
supply terminal of an integrated circuit
∆I
CC
Supply current change
The increase in supply current for each input that is at one of the specified TTL voltage levels rather than
0 V or V
CC
I
CEX
Output high leakage current
The maximum leakage current into the collector of the pulldown output transistor when the output is high
and the output forcing condition V
O
= 5.5 V
I
I(hold)
Input hold current
Input current that holds the input at the previous state when the driving device goes to a
high-impedance state
I
IH
High-level input current
The current into* an input when a high-level voltage is applied to that input
I
IL
Low-level input current
The current into* an input when a low-level voltage is applied to that input
I
off
Input/output power-off leakage current
The maximum leakage current into/out of the input/output transistors when forcing the input/output to
4.5 V and V
CC
= 0 V
I
OH
High-level output current
The current into* an output with input conditions applied that, according to the product specification,
establishes a high level at the output
*Current out of a terminal is given as a negative value.