SN54AS825A

Supply voltage, V_CC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . 7 V
Input voltage, V_I  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7 V
Voltage applied to a disabled 3-state output . . . . . . . . . . . . . . . . . . . . . . . . .  .. . . . . . . . . .5.5 V
Operating free-air temperature range, T_A:SN54AS825A  . . . . . . . . . . ..... . . . . .. .55 to 125
                                                                   SN74AS825A  . . . . . . . . . . . ..... . . .. . . . . .0 to 70
Storage temperature range  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..... . . . .65 to 150

These 8-bit flip-flops feature 3-state outputs designed specifically for driving highly capacitive or relatively low-impedance loads. SN54AS825A is particularly suitable for implementing multiuser registers, I/O ports, bidirectional bus drivers, and working registers.

With the clock-enable (CLKEN) input low, the eight D-type edge-triggered flip-flops enter data on the low-to-high transitions of the clock (CLK) input. Taking CLKEN high disables the clock buffer, latching the outputs. SN54AS825A has noninverting data (D) inputs. Taking the clear (CLR) input low causes the eight Q outputs to go low independently of the clock.

Multiuser buffered output-enable (OE1, OE2, and OE3) inputs can be used to place the eight outputs in either a normal logic state (high or low logic level) or a high-impedance state. In the high-impedance state, the outputs neither load nor drive the bus lines significantly. The highimpedance state and increased drive provide the capability to drive bus lines without interface or pullup components.

The output of SN54AS825A enables do 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 SN54AS825A is characterized for operation over the full military temperature range of 55 to 125. The SN74AS825A is characterized for operation from 0 to 70.