SN74LS399D ,QUAD 2-PORT REGISTERBLOCK DIAGRAM** * * * * ** * SN54/74LS398 only
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SN74LS399N3 ,Quadruple 2-Input Multiplexers With Storage17-Mar-2017PACKAGING INFORMATIONOrderable Device Status Package Type Package Pins Package Eco Plan ..
SN74LS423D ,Dual Retriggerable Monostable Multivibrators
SN74LS42N ,ONE-OF-TEN DECODERSN54/74LS42ONE-OF-TEN DECODERThe LSTTL/ MSI SN54/ 74LS42 is a Multipurpose Decoder designed to ac-c ..
SN74LS445N ,BCD-to-Decimal Decoders/Drivers 16-PDIP 0 to 70
SP204CT , 5V High-Speed RS-232 Transceivers with 0.1uF Capacitors
SP205EP , 5V High-Speed RS-232 Transceivers with 0.1uF Capacitors
SP205EP , 5V High-Speed RS-232 Transceivers with 0.1uF Capacitors
SP2060 , 20.0AMP Schottky Barrier Rectifiers
SP206BCT , 5V High-Speed RS-232 Transceivers with 0.1uF Capacitors
SP206BET , 5V High-Speed RS-232 Transceivers with 0.1uF Capacitors
SN54LS398J-SN74LS398N-SN74LS399D
QUAD 2-PORT REGISTER
QUAD 2-PORT REGISTERThe SN54/74LS398 and SN54/74LS399 are Quad 2-Port Registers. They
are the logical equivalent of a quad 2-input multiplexer followed by a quad 4-bit
edge-triggered register. A Common Select input selects between two 4-bit in-
put ports (data sources). The selected data is transferred to the output register
on the LOW-to-HIGH transition of the Clock input. The SN54/74LS398 fea-
tures both Q and Q inputs, while the SN54/74LS399 has only Q outputs. Select From Two Data Sources Fully Positive Edge-Triggered Operation Both True and Complemented Outputs on SN54/74LS398 Input Clamp Diodes Limit High-Speed Termination Effects
CONNECTION DIAGRAM DIP (TOP VIEW)------ -- ---- ----- -- -- - -- ------- --- - -- -- ---- -- -- -- -- -- -- -- - -
PIN NAMES LOADING (Note a) Common Select Input Clock (Active HIGH Going Edge) Input
I0a–I0d Data Inputs From Source 0
I1a–I0d Data Inputs From Source 1
Qa–Qd Register True Outputs (Note b)
Qa–Qd Register Complementary Outputs
(Note b)
NOTES:
a) 1 TTL Unit Load (U.L.) = 40 μA HIGH/1.6 mA LOW.
b) The Output LOW drive factor is 2.5 U.L. for Military (54) and 5 U.L. for Commercial
(74) Temperature Ranges.
