SN74AHC594QPWRQ1

Shift Registers Overview

The SN74AHC594-Q1 is an automotive-grade, 8-bit serial-in, parallel-out shift register with an output storage register. It operates within a supply voltage range of 2V to 5.5V and supports temperatures from -40°C to +125°C. The device features separate positive-edge triggered clocks for the shift (SRCLK) and storage (RCLK) registers, along with active-low asynchronous clear inputs (SRCLR, RCLR). It includes a serial output (QH') for cascading and balanced CMOS push-pull outputs.

Shift Registers Feature Summary

• AEC-Q100 qualified for automotive applications with specified temperature grades and ESD classifications.
• Includes wettable flank QFN package options to facilitate automatic optical inspection.
• Features balanced CMOS push-pull outputs capable of sourcing and sinking similar currents.
• Provides independent clocking and clearing for internal shift and output storage registers.

Shift Registers Applications

• Increasing the number of available outputs on a microcontroller
• Temporarily storing up to 8 bits of data
• Controlling seven-segment displays

Shift Registers Procurement Notes

Verify that the specific ordering suffix matches the required package type, as the SN74AHC594-Q1 family includes both TSSOP and WQFN variants. Confirm the component meets AEC-Q100 Grade 1 requirements for your target operating temperature range. Ensure input signals transition quickly to prevent oscillation due to standard CMOS input characteristics.

Shift Registers Selection Notes

Select this component when an automotive-qualified shift register with separate storage control is needed. It is suitable for designs requiring simple GPIO control without complex communication interfaces. Consider the wettable flank option if automated optical inspection reliability is a priority. Verify that the load capacitance does not exceed recommended limits to maintain switching performance.

Shift Registers Part Context

This part belongs to the Texas Instruments SN74AHC594-Q1 family of automotive logic devices. It is designed to replace standard shift registers in automotive environments where extended temperature ranges and high reliability are mandatory. The device integrates latching logic circuitry to maintain volatile memory states during operation.

Shift Registers Replacement Considerations

SN74AHC594PWQ1

Shift Registers FAQ

What happens to the latch state at power-up?

At power-up, the state of each latch is unknown because there is no default state defined for the latching logic circuits upon start-up.

How should unused standard CMOS inputs be handled?

Unused inputs must never be left floating. They should be terminated directly to VCC or GND, or connected via a pull-up/pull-down resistor to ensure valid input voltages.