CRD-4525-D1 Cirrus Logic Inc, CRD-4525-D1 Datasheet - Page 29

• Manufacturer Part Number: CRD-4525-D1
• Description: Audio Modules & Development Tools Eval Bd PWM Contrlr+ PwrStg_4Lyr 1oz Cu
• Manufacturer: Cirrus Logic Inc

Specifications of CRD-4525-D1

• Description/function: Audio Amplifiers
• Product: Audio Modules
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

CRD4525-Q1
9. THERMAL DE-RATING
The CRD4525-Q1 is a four-layer PCB design with 1 oz. (0.036 mm thick) copper. These parameters affect the ther-
mal resistance and, since the PCB acts as a heat sink for the CS4525, the maximum sustained output power of the
CRD4525-Q1. The CS4525 will generate heat that will flow into the PCB and then out to the ambient air surrounding
the CRD4525-Q1; the more output power the CS4525 is delivering, the more heat it will produce. This transfer of
heat is less effective at greater ambient temperatures. Because of this, there is a function between the ambient tem-
perature and the maximum sustained output power the CS4525 can deliver before heating to the point of thermal
error. This function is commonly detailed in a thermal de-rating curve, which describes how an amplifiers’ rated out-
put power is affected by ambient temperature. The thermal de-rating curve of a typical CRD4525-Q1 is shown in
Figure
20.
Figure 20. Thermal De-Rating Curve for a Typical CRD4525-Q1
For more information concerning thermal considerations of QFN packages, please refer to Cirrus Logic application
note AN315.
DS804RD4
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