SX1441EVK Semtech, SX1441EVK Datasheet - Page 23

• Manufacturer Part Number: SX1441EVK
• Description: KIT DEV FOR SX1441
• Manufacturer: Semtech
• Series: EasyBlue™r
• Type: Bluetoothr

Specifications of SX1441EVK

• For Use With/related Products: SX1441
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Contents: -
• Other names: SX1441DVK; SX1441DVK

Personal Area Network
3.5.8.1
The high prescaler is made up of an 8-stage dividing chain. It can be driven with the RC oscillator clock or the
SYS_CLOCK pin, depending on the EnableSysClock parameter.
The Table 23 summarizes which peripherals use the outputs of the high prescaler. Since each stage of the high
prescaler divides the frequency by 2, the frequency of all the outputs of the high prescaler is proportional to the
frequency of ckRCext.
3.5.8.2
The low prescaler can be driven from one of the high prescaler outputs ckRCext/2 to ckRCext/128 or directly with
the SLW_CLOCK_OUT pin when the bit EnableSlwClock is set to 1 and bit EnableSysClock is reseted to 0. The
bit ResPre in the register RegSysPre0 synchronously resets the low prescaler. The low prescaler is also
automatically cleared when the bit EnableSlwClock is set to 1. The bit ColdSlwClock value is 1 to indicate that
the SLW_CLOCK_IN is in its starting phase. It automatically enters this phase when the bit EnableSlwClock is set
to 1. During this phase, SLW_CLOCK_IN is not available. It becomes available after 32’768 cycles, when the bit
ColdSlwClock returns to 0.
© Semtech 2006
High prescaler output
ckRCext
ckRCext/2
ckRCext/4
ckRCext/8
ckRCext/16
ckRCext/32
ckRCext/64
ckRCext/128
High Prescaler
Low Prescaler
ckRCext
Peripherals
application UART, Bluetooth UART, SPI, counter/timer, port PA
application UART, Bluetooth UART
application UART, Bluetooth UART, SPI, counter/timer
application UART, Bluetooth UART, SPI
application UART, Bluetooth UART, SPI
application UART, Bluetooth UART
application UART, Bluetooth UART
application UART, Bluetooth UART
Figure 12 - High prescaler block diagram
Table 23 - High prescaler outputs usage
÷ 2
÷ 2
÷ 2
÷ 2
÷ 2
÷ 2
÷ 2
÷ 2
23
ckRCext/2
ckRCext/4
ckRCext/8
ckRCext/16
ckRCext/32
ckRCext/64
ckRCext/128
ckRCext/256
SX1441 – Bluetooth® 1.2 SoC
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Data Sheet