User's Manual

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Note d’étude / Technical document : URD1– OTL 5665.1– 002 / 70 884 Edition 03
Document Sagem Communications Reproduction et divulgation interdites
Sagem Communications document. Reproduction and disclosure prohibited
Figure 22: Layout of audio differential signals on a layer n
Figure 23: Adjacent layers of audio differential signals
(1).
Warning: Magnetic field generated by VBAT tracks may disturb the speaker, causing audio burst noise. In
this case, one shall modify routing of the VBAT tracks to reduce the phenomena.
8.2 EXAMPLE OF LAYOUT FOR CUSTOMER’S BOARD
The figure Figure 24 shows an example of layer allocation for a 6 layers circuit (for reference only):
Figure 24: layer allocation for a 6 layers circuit
9. RECOMMANDATIONS FOR CUSTOMER INDUSTRIALIZATION
Please note for following chapters that except where standards are indicated, the given characteristics should be
considered as validated conditions used on Sagem Communication product.

Other conditions depending of the customer’s factory process are not validated but can be submitted to
Sagem Communication for proficiency.
9.1 MOISTURE LEVEL
According to IPC/JEDEC J-STD 20, the HiloNC has the following MSL level : 3 (Targeted).
Layer n-1
Layer n
Layer n+1
GND
HSET_OUT_P
GND
GND
HSET_OUT_P
GND
HSET_OUT_N
Layer 1: Components (HiloNC)
Layer 2: Bus
Layer 3: Power supply
Layer 4: Complete GND layer
Layer 5: Audio, clocks, sensitive signals
Layer 6: GND,test points