WM8990ECS/RV Wolfson Microelectronics, WM8990ECS/RV Datasheet - Page 10

• Manufacturer Part Number: WM8990ECS/RV
• Description: Audio CODECs Stereo CODEC w.Class AB/D speaker driver
• Manufacturer: Wolfson Microelectronics

Specifications of WM8990ECS/RV

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

WM8990
w
SPEAKER POWER DE-RATING CURVE
The speaker driver has been designed to drive a maximum of 1W into 8Ω with a 5V supply.
However, thermal restrictions defined by the W-CSP package Ө
be safely dissipated in the device without exceeding the maximum operating junction temperature.
Power dissipated in the device correlates directly with speaker efficiency, hence there are separate
de-rating curves for class D and class AB operation.
Under no circumstances should the recommended maximum powers be exceeded.
CLASS D DE-RATING CURVES
The de-rating curves shown in Figure 2 are based on a full scale sinusoidal input.
Figure 2 Class D Speaker Power De-Rating Curve
[W]
P
1.0
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
SPKVDD = 3.6V
SPKVDD = 3.3V
SPKVDD = 2.7V
SPKVDD = 3V
SPKVDD = 5.5V
55
60
65
SPKVDD = 5V
70
75
JA
SPKVDD = 4.2V
limit the amount of power that can
80
85
PD, March 2009, Rev 4.0
[ºC]
T
Production Data
10