These 9-bit flip-flops feature 3-state outputs designed specifically for driving highly capacitive or relatively low-impedance loads. These devices are particularly suitable for implementing wider buffer registers, I/O ports, bidirectional bus drivers, parity bus interfacing, and working registers.
With the clock-enable (
)
input low, the nine D-type edge-triggered flip-flops enter data on
the low-to-high transitions of the clock (CLK) input. Taking high disables the clock buffer,
latching the outputs. The SN54AS823A and SN74AS823A have noninverting
data (D) inputs and the SN74AS824A has inverting (D\) inputs. Taking
the clear (
) input low
causes the nine Q outputs to go low independently of the clock.
A buffered output-enable (
) input can be used to place the nine outputs in either
a normal logic state (high or low logic level) or the high-
impedance state. In the high-impedance state, the outputs neither
load nor drive the bus lines significantly. The high-impedance state
and increased drive provide the capability to drive bus lines without
interface or pullup components.
does not affect
the internal operation of the flip-flops. Old data can be retained or
new data can be entered while the outputs are in the high-impedance
state.
The SN54AS823A is characterized for operation over the full military temperature range of -55°C to 125°C. The SN74AS823A and SN74AS824A are characterized for operation from 0°C to 70°C.
| Type | Title | Date | ||
|---|---|---|---|---|
| * | Data sheet | 9-Bit Bus Interface Flip-Flops With 3-State Outputs datasheet (Rev. A) | 01 Aug 1995 | |
| * | SMD | SN54AS823A SMD 5962-89525 | 21 Jun 2016 | |
| Application note | Power-Up Behavior of Clocked Devices (Rev. B) | PDF | HTML | 15 Dec 2022 | |
| Selection guide | Logic Guide (Rev. AB) | 12 Jun 2017 | ||
| Application note | Understanding and Interpreting Standard-Logic Data Sheets (Rev. C) | 02 Dec 2015 | ||
| User guide | LOGIC Pocket Data Book (Rev. B) | 16 Jan 2007 | ||
| Application note | Semiconductor Packing Material Electrostatic Discharge (ESD) Protection | 08 Jul 2004 | ||
| Application note | TI IBIS File Creation, Validation, and Distribution Processes | 29 Aug 2002 | ||
| Application note | Designing With Logic (Rev. C) | 01 Jun 1997 | ||
| Application note | Advanced Schottky Load Management | 01 Feb 1997 | ||
| Application note | Input and Output Characteristics of Digital Integrated Circuits | 01 Oct 1996 | ||
| Application note | Live Insertion | 01 Oct 1996 | ||
| Application note | Advanced Schottky (ALS and AS) Logic Families | 01 Aug 1995 |
For additional terms or required resources, click any title below to view the detail page where available.
| Package | Pins | Download |
|---|---|---|
| CDIP (JT) | 24 | View options |
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