Smaller is better, right? Not always. As our space-constrained, feature-packed applications demand smaller device packaging, all ICs are affected – including little logic. But, what typically happens when we create smaller and smaller packages for little logic ICs is that the pin pitch also gets smaller. This makes installing them on printed circuit boards terribly difficult. Manufacturing board shops are forced to change their soldering procedures to adapt to the smaller pin pitches.
Not anymore. Texas Instruments just released its new DPW package for little logic – a major breakthrough in IC packaging. This new DPW package is a tiny 0.8 mm square – 56% smaller than the DRY package – but still has the .5mm lead pitch that industry is accustomed to, eliminating complicated installation that traditionally hindered small packages. This was accomplished in a unique way where the center thermal pad is used as a ground, allowing more room for the functional pads. The thermal pad also assists in heat dissipation when needed. The popular functions of the LVC family (such as the SN74LVC1G08) of little logic are available now and the AUP functions are on the way.
Here we show the comparison to existing packages:
Layout guidelines to keep in mind when using these little logic ICs:
When using multiple bit logic devices inputs should not ever float. In many cases, functions or parts of functions of digital logic devices are unused; for example, when only two inputs of a triple-input AND gate are used or only 3 of the 4 buffer gates are used. Such input pins should not be left unconnected because the undefined voltages at the outside connections result in undefined operational states. Specified below are the rules that must be observed under all circumstances. All unused inputs of digital logic devices must be connected to a high or low bias to prevent them from floating. The logic level that should be applied to any particular unused input depends on the function of the device. Generally they will be tied to Gnd or Vcc whichever make more sense or is more convenient.
Will this new package help solve your design issues?
For more information:
- Sample the sn74lvc1g08
- Download the Little Logic Guide
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