LG KT520 Service Manual page 36

D. Master Clock and Clock Request Interface
The master clock (MCLK) is a 26 MHz signal used as the high precision clock signal for the Bluetooth
module. The signal can be switched on and off by the platform. The master clock request (CLKREQ) is
used by the Bluetooth module to ask for the master clock.
If the Bluetooth module asserts the signal high, it gets the master clock. The other alternative for the
Bluetooth module is to set the clock request output to high impedance state, indicating that it does not
need the master clock. The Bluetooth module receives the master clock, if other parts of the chipset
request it.
E. Low Frequency Clock Interface
The low-frequency clock signal (RTCCLK) is used by the Bluetooth module as a low-power clock. The
clock is used in different Bluetooth modes, like sniff and park, to have a correct timing on the Bluetooth
air interface without having the master clock running.
The low-frequency clock is always present, in some applications even when the chipset is powered
down.
F. STLC2500C
■ Bluetooth™‚ specification compliance: V2.0 + EDR.
■ Based on Ericsson Technology Licensing Baseband Core (EBC)
■ Point-to-point, point-to-multi-point (up to 7 slaves) and scatternet capability
■ Asynchronous Connection Oriented (ACL) logical transport link
■ Synchronous Connection Oriented (SCO) link:
2 simultaneous SCO channels
■ Supports Pitch-Period Error Concealment (PPEC)
- Improves speech quality in the vicinity of interference like e.g. WLAN
- Used with CVSD air coding
- Works at receiver, no Bluetooth implication
■ Adaptive Frequency Hopping (AFH): hopping kernel, channel assessment as Master and as Slave
■ Faster Connection: Interlaced scan for Page and Inquiry scan, first FHS without random back off,
RSSI used to limit range
■ Extended SCO (eSCO) links
Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
3. TECHNICAL BRIEF
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