SCAS526E August 1995 – July 2025 SN54ACT10 , SN74ACT10
PRODUCTION DATA
Refer to the PDF data sheet for device specific package drawings
In this application, two 3-input NAND gates are used to create an active-low SR latch as shown in Figure 9-1. The additional gate can be used elsewhere in the system, or the inputs can be grounded and left unused.
The SNx4ACT10 is used to drive the tamper indicator LED and provide one bit of data to the system controller. When the tamper switch outputs LOW, the output Q becomes HIGH. This output remains HIGH until the system controller addresses the event and sends a LOW signal to the R input which returns the Q output back to LOW.