SN54HCT574

· Inputs Are TTL-Voltage Compatible
· High-Current 3-State Noninverting Outputs Drive Bus Lines Directly or up to 15 LSTTL Loads
· Bus-Structured Pinout
· Package Options Include Plastic Small-Outline (DW), Thin Shrink Small-Outline (PW), and Ceramic Flat (W) Packages, Ceramic Chip Carriers (FK), and Standard Plastic (N) and Ceramic (J) 300-mil DIPs

Supply voltage range, V_CC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 0.5 V to 7 V
Input clamp current, I_IK (V_I < 0 or V_I > V_CC) (see Note 1) . . . . . . . . . . . . . . . . . . . .. . . . . . .  . . ±20 mA
Output clamp current, I_OK (V_O < 0 or V_O > V_CC) (see Note 1) . . . . . . . . . . . . . . . . . . . . .. . . . . . ±20 mA
Continuous output current, I_O (V_O = 0 to V_CC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±35 mA
Continuous current through V_CC or GND . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±70 mA
Package thermal impedance, _JA (see Note 2): DW package . . . . . . . . . . . . . . . . . . . . . . . . . . . 97°C/W
                                                                           N package . . . . . . . . . . . . . . . . . . . . . .  . . . . . . 67°C/W
                                                                           PW package . . . . . . . . . . . . . . . . . . . . . . . . . . 128°C/W
Storage temperature range, T_stg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65°C to 150°C

‡ Stresses beyond those listed under "absolute maximum ratings" may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated under "recommended operating conditions" is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
NOTES: 1. The input and output voltage ratings may be exceeded if the input and output current ratings are observed.
2. The package thermal impedance is calculated in accordance with JESD 51, except for through-hole packages, which use a trace length of zero.

These octal edge-triggered D-type flip-flops of SN54HCT574 feature 3-state outputs designed specifically for bus driving. They are particularly suitable for implementing buffer registers, I/O ports, bidirectional bus drivers, and working registers.

The eight flip-flops of SN54HCT574 enter data on the low-to-high transition of the clock (CLK) input. A buffered output-enable (OE) input can be used to place the eight outputs in either a normal logic state (high or low logic levels) or the high-impedance state. In the high-impedance state, the outputs of SN54HCT574 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.

OE does not affect the internal operations of the flip-flops. Old data of SN54HCT574 can be retained or new data can be entered while the outputs are in the high impedance state.

The SN54HCT574 is characterized for operation over the full military temperature range of 55°C to 125°C. The SN74HCT574 is characterized for operation from 40°C to 85°C.