Contents
Where is the thermal pad on a QFN?
The QFN package is designed so that the lead frame die pad (or thermal pad) is exposed on the bottom of the IC (see Figure 1). This provides an extremely low thermal resistance (θJC) path between the die and the exterior of the package. Figure 1. Section View of a QFN Package
Why is the die attach pad exposed on a QFN?
QFN/SON are also designed with the die attach pad exposed at the bottom side to create an efficient heat path to the PCB. Heat transfer can be further facilitated by metal vias in the thermal land pattern of the PCB. The exposed pad also enables ground connection.
What’s the difference between a son and a QFN?
SON is sometimes also referred as DFN: Dual flat no-lead package. QFN/SON are also designed with the die attach pad exposed at the bottom side to create an efficient heat path to the PCB. Heat transfer can be further facilitated by metal vias in the thermal land pattern of the PCB.
What does WF stand for on a QFN?
Wettable flanks (WF) are modifications to the fully-exposed terminal ends, which promote solder wetting for the formation of a solder fillet.
Is the SMT breakout PCB for 48 QFN or 48 tqfp-3?
SMT Breakout PCB for 48-QFN or 48-TQFP – 3 Pack! Beguiled by a fancy new chip that is only available in a QFP or QFN pinout? This breakout PCB set will make your life much much easier and get you prototyping faster than ever. One side has a 48-QFP pin out with traces going to two rows of 0.1″ spaced holes, the other has 48-QFN (7mm body).
What do you need to know about the QFN package?
The QFN package is a thermally enhanced standard size IC package designed to eliminate the use of bulky heat sinks and slugs. This package can be easily mounted using standard PCB assembly techniques and can be removed and replaced using standard repair procedures.
How big is a QFN with 32 leads?
For example, the footprint of a 32-lead thin quad flat pack (TQFP) is 81 mm2 (7.0 mm × 7.0 mm body with a 9.0 mm × 9.0 mm footprint, including package leads). The equivalent QFN with 32 leads (Figure 1) is only 25 mm2 (5.0 mm × 5.0 mm body with no extended leads).
How big should thermal pad be for vias?
particular user’s surface mount practices and requirements. behind the recommended land pad patterns. Normally, the size of the thermal pad should at least match the exposed die paddle size. clearance for vias, the thermal pad size may need to be reduced to less than the package paddle size.
What makes a dual row QFN so compact?
The dual-row or multi-row QFN package utilizes an interstitial lead design that results in a staggered lead arrangement. The inner row is offset 0.5 mm, which results in a compact design that maximizes die size while not exceeding the surf ace mount technology (SMT) capability of a typical 0.5 mm pitch SMT process.