Kenwood NX-5300 Service Manual page 21

2.4.9.2 GPS Circuit
The RF signal is received by the antenna matched by the matching circuit. The matching circuit consists of L905, C948 and C883.
And this signal applied to a high-pass filter. The filter consists of C882, C881, C880, L859 and L858. The filtered RF signal is then
applied to a SAW filter (L857).
The output of the SAW filter is fed into the LNA (IC851). The LNA is enabled by GPS_EXT_LNA_EN (pin H6 of the BT/GPS IC, IC850).
The LNA input match comprises of C879, C878 and L856. The LNA output match comprises of C874. And through the Attenuator
comprised of R857, R856 and R855, the RF signal is further filtered by a second SAW filter (L853).
The output of the second SAW filter is passed to pin L2 of the BT/GPS IC. The input match for pin L2 comprises of C867, C866 and
L852. The control and data lines for the BT/GPS IC are GPS_PA_EN, BTFM_nSHUTDOWN, GPS_TX and GPS_RX. GPS_TX and
GPS_RX are shared with the Bluetooth data line.
Frequency configuration for GPS is following:
Lo is GPS: 1571.324MHz
GPS antenna
Matching
HPF
2.5 COMPONENTS DESCRIPTION
2.5.1 TX-RX unit (XC1-0341-8X, XC1-0370-1X)
Ref. No. Part Name
IC20 IC
IC30 IC
IC31 IC
IC32 IC
IC33 IC
IC34 IC
IC35 IC
IC36 IC
IC37 IC
IC38 IC
IC39 IC
IC60 IC
IC61 IC
IC63~65 IC
IC70 IC
IC80 IC
IC81 IC
IC82 IC
IC100 IC
IC101 IC
IC102 IC
IC200 IC
IC201 IC
IC300 IC
LNA Supply
LNA Enable
Pre-SAW LNA
Attenuator
TCXO
19.2MHz
Fig.7 GPS circuit
Description
Reset
Voltage regulator (33SD)
Voltage regulator (31BU)
Voltage regulator (12BU)
DC/DC converter (38M)
DC/DC converter (18M)
Voltage regulator (33M)
Voltage regulator (50C)
Voltage regulator (18BT)
Voltage regulator (33BT)
Voltage regulator (33A)
DC/DC converter (200C)
Voltage regulator (33C)
Voltage regulator (50R/50T/
50VCO)
Voltage regulator (53AF)
Voltage regulator (30M)
Voltage regulator (33OPT)
Voltage regulator (50A)
PLL IC
DC AMP
Voltage regulator (53AF)
PLL IC
DC AMP
Pre-drive AMP 1
IC850 BT/GPS IC
VDD_TCXO(G1) VBAT1(A2)
TCXO_LDO_IN(H1)
GPS_EXT_LNA_EN(H6)
GPS IC(IC850)
GPS_LNA_IN(L2)
BT_HCI_UART_TX(A4)
Post-SAW
BT_HCI_UART_RX(B5)
BTFM_nSHUTDOWN(A6)
IC700
GPS PA EN(G3)
Clock
TCXO_CLK_LV(F1)
Buffer
RTC_CLK(H9)
Ref. No. Part Name
IC360 IC
IC400, IC
401
IC550, IC
551
IC600 IC
IC700 IC
IC701 IC
IC702 IC
IC703 IC
IC704 IC
IC705 IC
IC706 IC
IC708 IC
IC709 IC
IC711,712 IC
IC800 IC
IC801 IC
IC802 IC
IC803 IC
IC804,805 IC
IC806 IC
IC850 IC
IC851 IC
IC852,853 IC
IC900 IC
3.3V
1.8V
VDDS
IC702
GPS_TX
LEVEL
GPS_RX
SHIFT
MPU/DSP
OSCILLATOR
32.768kHz
Description
DC SW (Antenna SW)
APC
DC AMP
IF IC
Clock buffer
DC SW (18M)
MPU
SDRAM
Reset
Flash memory
Logic control
I/O control
Motion sensor
Logic control
LED driver
Voltage regulator (50U)
Analog SW
Level converter
Logic control
Logic control
GPS/Bluetooth
GPS LNA
Level converter
A/D converter
(No.RA015<Rev.002>)1-21