wm9001 Wolfson Microelectronics plc, wm9001 Datasheet - Page 6

• Manufacturer Part Number: wm9001
• Description: 1w Dual-mode Class Ab/d Speaker Driver
• Manufacturer: Wolfson Microelectronics plc

WM9001
PARAMETER
Operating temperature range
Operating junction temperature
Thermal Resistance
THERMAL PERFORMANCE
w
Thermal analysis should be performed in the intended application to prevent the WM9001 from
exceeding maximum junction temperature. Several contributing factors affect thermal performance
most notably the physical properties of the mechanical enclosure, location of the device on the PCB
in relation to surrounding components and the number of PCB layers. Connecting the GND
pins/paddle through thermal vias and into a large ground plane will aid heat extraction.
Three main heat transfer paths exist to surrounding air:
The temperature rise T
The junction temperature T
-
-
-
-
-
Package top to air (radiation).
Package bottom to PCB (radiation).
Package pins/paddle/balls to PCB (conduction).
P
Ө
and is therefore a measure of heat transfer from the die to surrounding air. Ө
determined with reference to JEDEC standard JESD51-9.
D
JA
SYMBOL
is the power dissipated in the device.
is the thermal resistance from the junction of the die to the ambient temperature
Ө
T
T
JA
A
R
J
is given by T
J
is given by T
R
= P
J
D
= T
MIN
-40
-40
* Ө
A
JA
+T
R
, where T
TYP
52
A
is the ambient temperature.
MAX
100
85
PP, June 2009, Rev 3.2
Pre-Production
°C/W
UNIT
°C
°C
JA
is
6