User's Manual

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2. Electrical Characteristic
1.1 Absolute Maximum Ratings
Symbol
Parameter
Min
Typ
Max
Units
3.3V
Power supply voltage with respect to VSS
3.3
4.0
V
T
storage
Storage Temperature
-55
125
℃
1.2 Recommended Operating Conditions
Symbol
Parameter
Min
Typ
Max
Units
3.3V
Power supply voltage with respect to VSS
2.97
3.3
3.63
V
T
A
Ambient operating temperature
-40
85
℃
1.3 Clock Specifications
1.3.1 External Sleep Clock Timing
External Sleep Clock is necessary for two reasons:
1. Auto frequency Detection
This is where the internal logic will bin the Ref clock source to figure out what is the reference clock frequency
is. This is done so no strapping is needed for telling 88W8997 what the ref clock input is.
2. Allow low current modes for BT to enter sleep modes such as sniff modes.
The AW-CB250NF external sleep clock pin is powered from the 3.3V voltage supply.
Symbol
Parameter
Min
Typ
Max
Units
CLK
Clock Frequency Range/accuracy
+-250ppm (initial, aging, temperature)
32.768
KHz
1.4 Reset Configuration
The AW-CB250NF is reset to its default operating state under the following conditions:
 Power-on reset (POR)
 Software/Firmware reset
 External pin for power down (PDn)