Bus interface registers
10-bit bus interface register, non-inverting (3-State)
10-bit bus interface register, inverting (3-State)
9-bit bus interface register, non-inverting (3-State)
9-bit bus interface register, inverting (3-State)
8-bit bus interface register, non-inverting (3-State)
8-bit bus interface register, inverting (3-State)
• High speed parallel registers with positive edge-triggered D-type
• High performance bus interface buffering for wide data/address
paths or busses carrying parity
• High impedance PNP base inputs for reduced loading (20µA in
high and low states)
• IIL is 20µA vs 1000µA for AM29821 series
• Buffered control inputs to reduce AC effects
• Ideal where high speed, light loading, or increased fan-in as
required with MOS microprocessor
• Positive and negative over-shoots are clamped to ground
• 3-State outputs glitch free during power-up and power-down
• Slim Dip 300 mil package
• Broadside pinout compatible with AMD AM 29821-29826 series
• Outputs sink 64mA and source 24mA
• Industrial temperature range available (–40°C to +85°C) for
The 74F821 series bus interface registers are designed to
eliminate the extra packages required to buffer existing registers and
provide extra data width for wider data/address paths of busses
The 74F821/74F822 are buffered 10-bit wide versions of the popular
The 74F822 is the inverted output version of 74F821.
The 74F823 and 74F824 are 9-bit wide buffered registers with clock
enable (CE) and master reset (MR) which are ideal for parity bus
interfacing in high microprogrammed systems.
The 74F824 is the inverted version of 74F823.
The 74F825 and 74F826 are 8-bit buffered registers with all the
74F823/74F824 controls plus output enable (OE0, OE1, OE2) to
allow multiuser control of the interface, e.g., CS, DMA, and RD/WR.
They are ideal for uses as an output port requiring high IOL/IOH.
The 74F826 is the inverted version of 74F825.
24-pin plastic slim DIP (300mil)
24-pin plastic SOL
VCC = 5V ±10%,
Tamb = 0°C to +70°C
N74F821N, N74F822N, N74F823N,
N74F824N, N74F825N, N74F826N
VCC = 5V ±10%,
Tamb = –40°C to +85°C
N74F821D, N74F822D, N74F823D,
N74F824D, N74F825D, N74F826D
PKG. DWG. #
1996 Jan 05
2 853-1304 16195