Kenwood NX-5700HB, Руководство по обслуживанию

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1-24 (No.RA073<Rev.001>)
2.4.9 Bluetooth/GPS Circuit
The main component of the Bluetooth/GPS circuit is Bluetooth / GPS IC (IC5) on Module (BT/GPS) unit.
The clocks of Bluetooth/GPS IC require 19.2MHz for core and 32.768kHz slow clock (X1 and X2) for UART.
Bluetooth/GPS IC communicates to the MPU/DSP (IC706) on the HCI UART. Interface of UART & Digital audio (PCM) between the
MPU/DSP (IC706) and the Bluetooth/GPS IC (IC5), have level conversion at the level shift IC (IC6 and IC7) on Module (BT/GPS) unit.
The Bluetooth/GPS IC is powered by 1.8V and 3.3V which are supplied from 2 discrete external regulators (IC2 and IC3) on Module
(BT/GPS) unit.
Fig.5 Bluetooth/GPS circuit
2.4.9.1 Bluetooth Circuit
The Bluetooth / GPS IC (IC5) supports the Bluetooth 4.0 up to HCI level.
 Basic Rate
TX/RX frequency is 2400-2483.5MHz (79ch Hopping, 2402-2480MHz, 1MHz step). Transmitting power is +2dBm (Max.: +4dBm) at
Bluetooth antenna input.
 Low Energy
TX/RX frequency is 2400-2483.5MHz (40ch (3 advertising channel: Single carrier, 37data channel: Hopping), 2402-2480MHz, 2MHz
step). Transmitting power is +2dBm (Max.: +4dBm) at Bluetooth antenna input.
 Common
Using the printed antenna with Bluetooth, and it is connected to the Bluetooth / GPS IC (IC5) through the saw filter (L11).
Frequency configuration for Bluetooth is following:
There are 2 LO modes: 2X and Offset LO (OSLO). 2X where LO is 2*RF_FREQ (e.g. when transmitting at 2441MHz it is at 4882MHz).
OSLO where LO is at (2/3)*RF_FREQ (e.g. when transmitting at 2441MHz it is at 1627.333MHz).
In RX the 2X is always used.
In GFSK TX if power is >10dBm then OSLO is used
In EDR2 TX if power is >-12dBm then OSLO is used
In EDR3 TX if power is >-12dBm then OSLO is used
Otherwise 2X is used for TX as well.
2.4.9.2 GPS Circuit
The GPS RF signal is received with the active antenna, and connected to the Bluetooth / GPS IC (IC5) through the terminal (CN5)
and saw filter (L9).
The output is passed to pin L2 of the GPS IC. The input match for pin L2 comprises of C38, C36 and L7. The control and data lines
for the GPS IC are GPS_PA_EN, BTFM_nSHUTDOWN, GPS_TX and GPS_RX. GPS_TX and GPS_RX are shared with Bluetooth
data line.
Frequency configuration for GPS is following:
Lo is GPS: 1571.324MHz
Fig.6 GPS circuit
IC706
5 C I 6 C I
UART UART
UART
IC7
PCM PCM
PCM
X2 X1
CN5
BT/GPS IC
TCXO
19.2MHz 32.768kHz
Clock
BPF
Bluetooth
antenna
Level
shift IC
Level
shift IC
BPF
GPS
antenna
connector
Module (BT/GPS) unit
Main unit
MPU/DSP
BPF
GPS
antenna
TCXO
19.2MHz
MPU/DSP
1.8V
3.3V
GPS_LNA_IN(L2)
TCXO_CLK_LV(F1)
BT_HCI_UART_TX(A4)
BT_HCI_UART_RX(B5)
RTC_CLK(H9)
OSCILLATOR
32.768kHz
BTFM_nSHUTDOWN(A6)
GPS_PA_EN(G3)
VBAT1(A2)
LEVEL
SHIFT
TCXO_LDO_IN(H1)
VDDS
GPSTX
GPS_RX
BT
antenna
BT_RF
BT/GPS IC
Antenna
connector
BPF
GPS ANT ALM
GPS ANT PWR
GPS
antenna
detect
3.3V
33GPS
33BT
18BT
X2
X1
IC6, IC7
IC706
IC5