74HC573 - Octal D-type Transparent Latch IC

74HC573 IC Features and Specifications 

Here are some of the important features and specifications of the 74HC573 IC.

1. Operating voltage: –0.5 V to 7 V(Max)
2. Wide operating temperature: –55°C to 125
3. 3-State Outputs Directly Drive Bus Lines
4. Balanced Propagation Delays and Transition time
5. Can drive up to 15 LS-TTL Loads

 

Note: More technical information can be found in the 74HC573 Datasheet, linked at the bottom of this page.

 

74HC573 Pinout Configuration

The latch IC consists of 20 pins in total, the table below can be referred in order to understand the pin configuration of the IC.

Pin Number	Pin Type	Pin Description
1	OE’	3-state output enable input (active LOW)
2	1D	Data Input
3	2D	Data Input
4	3D	Data Input
5	4D	Data Input
6	5D	Data Input
7	6D	Data Input
8	7D	Data Input
9	8D	Data Input
10	GND	Ground
11	LE	latch enable input (active HIGH)
12	8Q	3-state latch output
13	7Q	3-state latch output
14	6Q	3-state latch output
15	5Q	3-state latch output
16	4Q	3-state latch output
17	3Q	3-state latch output
18	2Q	3-state latch output
19	1Q	3-state latch output
20	VCC	Positive suppy voltage

 

Working Principle and Logic Table of the IC

Working with the 74HC573 IC is pretty simple. Let us understand how the IC operates, when the Latch(LE) is HIGH, the Q outputs follows the D inputs, whereas, when the Latch(LE) is LOW, the Q output are latched at the logic levels of input D. The Output Enable(OE’) can be used to place the eight outputs in either a normal logic state (high or low).

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

 

Below is the truth table, with different input parameters and the output obtained at the Q lines.

 

Available Packages

PDIP, SOIC, CDIP

 

Alternatives

SN74AHCT573DWR, CD4099

 

Applications

Here are some of the applications of the transparent latch IC.

 

2D Model and Dimensions

Below is the 2D model of the IC, along with its dimensions in inches(millimeters). The following information can be used to design custom footprint of the IC for PCB designing and CAD modelling.