How many amperes is the output current of a general-purpose logic IC able to drive?

The current value that can be driven by the output of the general-purpose logic IC is explained based on the value described in the data sheet.

Related items are DC output current IOUT and DC Vcc current/ground current ICC/IGND.
IOUT is the maximum current that can be driven by one output, and ICC/IGND is the maximum current that can be driven by the entire IC.
Note that the following formula does not always hold when the number of outputs is n.

ICC/IGND / n = IOUT

Example: TC74ACT244FT
Table-1 is a copy of the Absolute Maximum Ratings table from the TC74ACT244FT datasheet. The TC74ACT244FT provides an IOUT of 50 mA and an ICC of 200 mA. When all the eight outputs provide an equal amount of current, the amount of current that each output can drive is calculated to be:

200 mA / 8 = 25 mA

Therefore, not all the outputs can drive an output current of 50 mA as specified as IOUT simultaneously.

Table-1 TC74ACT244FT Datasheet (Absolute Maximum Ratings)
Table-1 TC74ACT244FT Datasheet (Absolute Maximum Ratings)

Comparing absolute maximum ratings (Output Current IOUT and Power Supply /GND Current ICC/IGND) of Main Products in Each Series
Typical product used in the table-2

General-purpose logic IC :74xx244
One-gate logic (L-MOS:TC7S00, TC7PZ34, other series is TC7xx125)

The values in table-2 are values of representative products and show the tendency of each series. (This may change depending on the function you select.) Use this as a guide for designing.
Output current IOUT and DC Vcc current/ground current ICC/IGND are not specified for the Standard series.

Table-2 Comparison of output current and power supply/ground current absolute maximum ratings of representative products by series of general-purpose logic ICs

Items

 

Symbol

(Unit)

Series

Standard

High Speed

Advanced

Very High Speed

Low Voltage

Very Low Voltage

CMOS Logic ICs

One-Gate Logic

CMOS Logic ICs

One-Gate Logic

CMOS Logic ICs

CMOS Logic ICs

CMOS Logic ICs

One-Gate Logic

CMOS Logic ICs

One-Gate Logic

CMOS Logic ICs

One-Gate Logic

TC40
TC45

TC4S
TC4W

TC74HC
TC74HCT

TC7S

TC7W
TC7WT

TC74AC
TC74ACT

74VHC
74VHCT

74VHCV

TC7SH
TC7WH
TC7SET

74LCX

TC7SZ
TC7WZ

TC7PZ

TC74VCX

7UL1G
7UL1T

7UL2G
7UL2T

Output current

IOUT

(mA)

-

-

±35

±12.5

±35

±50

±25

±50

±25

±50

±50

±50

±50

±25

VCC/GND
Current

Icc/IGND

(mA)

-

-

±75

±25

±37.5

±200

±75

±100

±50

±100

±50

±100

±100

±50

Note: Any one of the absolute maximum ratings must not be exceeded even instantaneously.
Even when an IC is used at a temperature, current, and voltage within the absolute maximum rated and operating ranges, its reliability could degrade substantially if it is continuously exposed to heavy loads (e.g., high temperature, high current, high voltage, and large temperature changes). Be sure to build reliability into applications, referring to the Toshiba Semiconductor Reliability Handbook (particularly the sections on handling precautions and derating) and information on the reliability of individual devices (e.g., reliability test reports and estimated failure rates).

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