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Motorola Gp328plus Gp338plus Gp338xls Detailed 6804112j28 G Manual
Motorola Gp328plus Gp338plus Gp338xls Detailed 6804112j28 G Manual
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Frequency Generation Circuitry5B-9 6.0 Frequency Generation Circuitry The Frequency Generation Circuitry is composed of two main ICs, the Fractional-N synthesizer (U201), and the VCO/Buffer IC (U241). Designed in conjunction to maximize compatibility, the two ICs provide many of the functions that normally would require additional circuitry. The synthesizer block diagram illustrates the interconnect and support circuitry used in the region. Refer to the relevant schematics for the reference designators. The synthesizer is powered by regulated 5V and 3.3V which come from U247 and U248 respectively. The synthesizer in turn generates a superfiltered 4.5V which powers U241. In addition to the VCO, the synthesizer must interface with the logic and ASFIC circuitry. Programming for the synthesizer is accomplished through the data , clock and chip select lines from the microprocessor. A 3.3V dc signal from synthesizer lock detect line indicates to the microprocessor that the synthesizer is locked. Transmit modulation from the ASFIC is supplied to pin10 of U201. Internally the audio is digitized by the Fractional-N and applied to the loop divider to provide the low-port modulation. The audio runs through an internal attenuator for modulation balancing purposes before going out to the VCO. Figure 5-3: Frequency Generation Unit Block Diagram Vo l t a g e Multiplier Synthesizer U201 Dual Tran- sistor Loop Filter VCOBIC U241Low Pass Filter Matching Network Attenuator To Mixer To PA D r i v e rVCP Vmult1Aux3 Aux4 MOD Out Modulating Signal Vmult2Rx VCO Circuit Tx VCO CircuitTRB 16.8 MHz Ref. Osc.Rx Out Tx Out
5B-10Frequency Generation Circuitry 6.1 Synthesizer (Refer to UHF Synthesizer Schematic Diagram on page 5B-23) The Fractional-N Synthesizer uses a 16.8MHz crystal (FL201) to provide a reference for the system. The LVFractN IC (U201) further divides this to 2.1MHz, 2.225MHz, and 2.4MHz as reference frequencies. Together with C206, C207, C208, R204 and CR203 , they build up the reference oscillator which is capable of 2.5ppm stability over temperatures of -30 to 85×C. It also provides 16.8MHz at pin 19 of U201 to be used by ASFIC and LVZIF. The loop filter which consist of C231, C232, C233, R231, R232 and R233 provides the necessary dc steering voltage for the VCO and determines the amount of noise and spur passing through . In achieving fast locking for the synthesizer, an internal adapt charge pump provides higher current at pin 45 of U201 to put synthesizer within the lock range. The required frequency is then locked by normal mode charge pump at pin 43 . Both the normal and adapt charge pumps get their supply from the capacitive voltage multiplier which is made up of C258, C259, C228, triple diode CR201 and level shifters U210 and U211. Two 3.3V square waves ( 180 deg out of phase) are first shifted to 5V, then along with regulated 5V , put through arrays of diodes and capacitors to build up 13.3V at pin 47 of U201. Figure 5-4: Synthesizer Block Diagram DATA CLK CEX MODIN V CC, DC5V XTAL1 XTAL2 WARP PREIN VCP REFERENCE OSCILLATOR VOLTAGE MULTIPLIER VOLTAGE CONTROLLED OSCILLATOR 2-POLE LOOP FILTER DATA (U409 PIN 100) CLOCK (U409 PIN 1) CSX (U409 PIN 2) MOD IN (U404 PIN 40) +5V (U247 PIN 4)7 8 9 10 13, 30 23 24 25 32 47 VMULT2 VMULT1BIAS1 SFOUTAUX3 AUX4 IADAPTIOUTGND FREFOUTLOCK4 19 6, 22, 23, 24 43 45 3 2 28 14 1540FILTERED 5VSTEERING LINE LOCK (U409 PIN 56) PRESCALER INLO RF INJECTION TX RF INJECTION (1ST STAGE OF PA) FREF (U201 PIN 21 & U404 PIN 34) 39 BIAS2 41 DUAL TRANSIS DUAL TRANSIS-48 5VR5 5, 20, 34, 36 (U248 PIN 5) AUX1 V DD, 3.3VMODOUT U251 LOW VOLTAGE FRACTIONAL-N SYNTHESIZER TORSTORS
Frequency Generation Circuitry5B-11
6.2 VCO - Voltage Controlled Oscillator
(Refer to UHF Voltage Controlled Oscillator Schematic Diagram on page 5B-24)
Figure 5-5: VCO Block Diagram
The VCOBIC (U241) in conjunction with the Fractional-N synthesizer (U201) generates RF in both the
receive and the transmit modes of operation. The TRB line (U241 pin 19) determines which oscillator
and buffer will be enabled. A sample of the RF signal from the enabled oscillator is routed from U241
pin 12, through a low pass filter, to the prescaler input (U201 pin 32). After frequency comparison in
the synthesizer, a resultant CONTROL VOLTAGE is received at the VCO. This voltage is a DC
voltage between 3.5V and 9.5V when the PLL is locked on frequency.
Presc
RX
TXMatching
NetworkLow Pass
Filter
Attenuator Pin8
Pin14
Pin10 Level Shifter
Network5V
(U201 Pin28)
VCC Buffers
TX RF Injection U201 Pin 32AUX4 (U201 Pin3)AUX3 (U201 Pin2)
Prescaler Out
Pin 12 Pin 19 Pin 20
TX/RX/BS
Switching Network
U241
VCOBIC
Rx
Active Bias
Tx
Active Bias
Pin2
Rx-I adjustPin1
Tx-I adjustPins 9,11,17
Pin18Vsens
Circuit Pin15Pin16 RX VCO
Circuit
TX VCO
Circuit RX Tank
TX TankPin7
Vcc-Superfilter
Collector/RF in
Pin4
Pin5
Pin6
RX
TX
(U201 Pin28)Rx-SW
Tx-SW
Vcc-Logic
(U201 Pin28) Steer Line
Voltage
(VCTRL)Pin13
Pin3TRB_IN
LO RF INJECTION
VSFVSF VSF
5B-12Frequency Generation Circuitry The VCOBIC(U241) is operated at 4.54 V (VSF) and Fractional-N synthesizer (U201) at 3.3V. This difference in operating voltage requires a level shifter consisting of Q260 and Q261 on the TRB line. The operation logic is shown in Table 5-1. In the receive mode, U241 pin 19 is low or grounded. This activates the receive VCO by enabling the receive oscillator and the receive buffer of U241. The RF signal at U241 pin 8 is run through a matching network. The resulting RF signal is the LO RF INJECTION and it is applied to the mixer at T302 (refer to UHF Receiver Front End Schematic Diagram on page 5B-21). During the transmit condition, when PTT is depressed, five volts is applied to U241 pin 19. This activates the transmit VCO by enabling the transmit oscillator and the transmit buffer of U241. The RF signal at U241 pin 10 is injected into the input of the PA module (U101 pin16). This RF signal is the TX RF INJECTION. Also in transmit mode, the audio signal to be frequency modulated onto the carrier is received through the U201 pin 41. When a high impedance is applied to U241 pin19, the VCO is operating in BATTERY SAVER mode. In this case, both the receive and transmit oscillators as well as the receive transmit and prescaler buffer are turned off. Table 5-1: Level Shifter Logic Desired ModeAUX 4AUX 3TRB TxLowHigh (@3.2V)High (@4.8V) RxHighLowLow Battery SaverLowLowHi-Z/Float (@2.5V)
Notes For All Schematics and Circuit Boards 5C-13 7.0 Notes For All Schematics and Circuit Boards * Component is frequency sensitive. Refer to the Electrical Parts List for value and usage. 1.Unless otherwise stated, resistances are in Ohms (k = 1000), and capacitances are in picofarads (pF) or microfarads (µF). 2.DC voltages are measured from point indicated to chassis ground using a Motorola DC multime- ter or equivalent. Transmitter measurements should be made with a 1.2 µH choke in series with the voltage probe to prevent circuit loading. 3.Reference Designators are assigned in the following manner: 100 Series = Transmitter 200 Series = Frequency Generation 300 Series = Receiver 400/500 Series = Controller 600 Series = Keypad Board 4.Interconnect Tie Point Legend: UNSWB+ = Unswitch Battery Voltage (7.5V) SWB+ = Switch Battery Voltage (7.5V) R5 = Receiver Five Volts CLK = Clock Vdda = Regulated 3.3 Volts (for analog) Vddd = Regulated 3.3 Volts (for digital) CSX = Chip Select Line (not for LVZIF) SYN = Synthesizer DACRX = Digital to Analog Voltage (For Receiver Front End Filter) VSF = Voltage Super Filtered (5 volts) VR = Voltage Regulator 6-LAYER CIRCUIT BOARD DETAIL VIEWING COPPER STEPS IN PROPER LAYER SEQUENCE LAYER 1 (L1) LAYER 2 (L2) LAYER 3 (L3) LAYER 4 (L4) LAYER 5 (L5) LAYER 6 (L6) INNER LAYERS SIDE 1 SIDE 2
5C-14 Notes For All Schematics and Circuit Boards THIS PAGE INTENTIONALLY LEFT BLANK
Circuit Board/Schematic Diagrams and Parts List5B-158.0 Circuit Board/Schematic Diagrams and Parts List 40 J2001 B503 3 FL201 TP201 C247 C251 C285C289 C370 C374C386 C248 C273 C286 C276 C253 C271 C272 L282 3 L2431 L273 3 L2531 L271 L321Q261 3 4 Q241R333R339 R243R248 R253R260 SH241 C210 C211 C212 C213 C214 C220 C230 C257C260 C294 C292C229 C203 C217 C235 C228 C233 C238 C297 C291 CR201 L201 L202L203 L232 Q210 3 4 Q260 3 4 R256R255 SH201 U247 B504 C522 FL301PB502 R352 VR441 C325 C324 C323 L311 R351 SH323C328 C554 C396 C391 C397 PB501 Q315 Q316 R326 R300 R314 R316 R318 R319 R325 R327 R334 R335 R338RT300 RT301 VR300VR444 C331 C333 CR308 R342 R317 R336 TP202 TP302 C375 C320 C381 C319 C322 L309L310 R309 R308 R310 R348 SH303T301 3 46T302 3 4 6 C110 C114C118C119 C121 C122C125 C160 C165 C166C171 C112 C113 C115 C117C116 C120 C161C127 C131 C129 C169 L114L115 L106 L107 L108L109 L113 L160 R103 R104R106 R107 R108 R120 R171 R161R173 SH101 U101 9 8 161 C109 C11132 Q110 1 C101 C141 C102 C104 C103 C106C107CR101 CR102 L101 L102 L104 L105 SH100C308 C511 C512 C514 C302 C301C520 C303 C304 C305 CR301 CR302 L301 L302 PB505 R301R302 SH301VR443 C362 C384C385 C364 C351 C349 C350 C352C353 C354C363 CR310 L325 L332 Q320 R355 R322 R345R320 R321 R324 R346SH321C521PB504 VR440 C505 C502 Q505R506 R507 R505 VR501 C513 CR503 2 34 Q502 R501 R502 C140 L116 UHF (403-470MHz) Main Board Top Side PCB No. 8404077G05/G06/G07
5B -16Circuit Board/Schematic Diagrams and Parts List 2 S502 35 4 1 2S501 C8 C 4J101 4 3 2 J102 C108 C132 C173 C172 CR105H101 P100 Q111 3 4 R101 R170 R133 R172 C315 C321 C395 C313 C310 C314 C318 C380 C306 C311 C316 C317C312 CR304 CR305CR303 L340 L306 L307 L305 L304 R306 R307R347 R305 SH302 C309 C307 L303 Q301 R304R303R340 R328 C383 C390 C346C339 C340 C341 C342C343 C357C358 R344 13 25 37 1U301 C337 C329 C347 C348 C356 L314 SH322 C336C344 C360C355C361C382 L331R343 R350 C345 C334 C359 C327C330 C326 C338L330 Q302 R315R313R311 R312 B501 321 C503 CR306 CR501 F501 SH304C105 C130 C138C151 C170 C174C123 C126 C133 C128C135 C150 C152 C134 E101 L112 R102R329R109 R130 R131R132 25 9 17 U102 1VR439 C241 C246 C255 C281 C295 C372C252 C242 C243 C250 C244C245 C254 C371 C373 C378 CR241CR242 CR243 CR251L241 L281 L242 L251 Q310R330 R332R110 R112 R111 R242 R241 R251R244 R245 R252R254 R331 R349SH242U241 10 201 11C201 C264 C218 C223 C224 C231 C296C298 C202 C204 C206C207 C208 C219 C232 C234 C258 C259 C263 C265 C293 CR203 L261 R204 R281 R202 R201 R231R232 R233 SH202 13 25 37 1U201 U210 3 4 U211 3 4C277 C279 C523 C278 L505 U248 VR442 VR506 C525 C526 C527 C528 C529 C530 C531 C532 C533 C534 C535 C536 C537 C538 C539 C540 C541 C542 C543 C544 C545 C546 C547 C548 C549 C550 C551 C552 C553C555 R509 R510 R511 UHF (403-470MHz) Main Board Bottom Side PCB No. 8404077G05/G06/G07
Circuit Board/Schematic Diagrams and Parts List5B-17 ZMY0131016-O 40 J2001 B503 B504 FL201 13 4 6 SH201 TP201 C210 C211 C212 C213 C214C220 C230 C257C260 C292 C229 C203 C217 C235 C228 C233 C238 C297 C291 CR201 L201 L202 L203 L232 Q210 3 4 Q260 3 4R256R255U247 C294 C247 C251 C285C289 C370 C374 C386 C271 C272 C248 C273C286 C276 C253L282 3 L2431 L273 3 L2531 L271 L321 Q261 3 4 Q241R333R243R248 R253R260 R339 SH241C391 C328C397 C325 C522 C554 C324 C323 FL301 R351 L311PB502PB504 Q316 Q315 R326R334 R335 R338R300 R314 R316 R318 R319 R325 R327 R352 RT300 RT301 SH323 VR300 VR441 VR444 C375 C320 C319 C322 C381 L309L310 R309R308 R310 R348 SH303T301 346 T3023 4 6 TP202 TP302 C331 C333 C396 CR308 R336 R342 R317 C109 C110 C114C118 C119 C121 C122C125 C160 C165 C166C171 C 111 C112 C113 C115 C116 C117 C120 C161C127 C131 C129C169 L115 L106 L107 L108 L109L114 L113 L160 32 Q110 1 R103 R104R174 R106 R107 R108 R120 R171 R161R173 R175 R176 SH101 1 16 8 9U101C521 PB501 VR440 C362 C364 C351 C349 C350 C352C353 C354C363 C384 C385 CR310 L325L332 Q320R322 R345R320 R321 R324 R355 R346 SH321C505 C512 C513 C502Q505 Q502 R506 R505R507 VR501 C511 C514 C520CR503 2 34 R501 R502 VR443 C140 L116PB505 C308 C302C304 C301 C303 C305 CR301 CR302 L301 L302 R301 R302 SH301 C102 C104 C103 C106C107C175CR101 CR102 L101 L102 L104SH100 C101 C141 L105 UHF (403-470MHz) Main Board Top Side PCB No. 8404077G09
5B -18Circuit Board/Schematic Diagrams and Parts List ZMY0131017-O 2 S502 35 4 4C8 C S501 2 C108 CR160 J101 4 3 21 J102 R101 R170 CR103 P100 Q 111 3 4 C172 C132 C173 CR105 H101 R133R172R102 R130 R131C105 C309 C315 C321C395 C306 C311 C307 C310 C314 C318 C313C380 C316 C312 C317 CR304 CR305CR303 L340 L306 L307 L303 L305 L304 Q301 R306 R307R304 R303R347 R305 R340 R328SH302C337 C383C390 C329 C336 C344 C345 C346 C347 C348C334 C356C339 C340 C341 C342 C343 C357 C360 C355 C358 C359 C361 C382 L314 L331 R343 R350 R344 SH32213 25 37 1 U301 C327 C338 C330 C326L330 Q302 R315R313R311 R3121 2 3 C503 CR306F501 SH304B501 C277 C279 C278 L505 U248 VR506 CR501 C130 C138C151 C170 C174 C123 C126 C133 C128C135 C150 C152 C134 E101 L112 R109 R132 R136 R329 259 17 U102 1 VR439 C241 C246 C255 C281 C295 C371 C372 C373 C378 C242C243 C250 C244C245 C252 C254 CR241CR242 CR243 CR251 R349 L241 L281 L242 L251 Q310R330 R331 R332R110 R112 R 111 R242 R241 R251R244 R245 R252R254 SH242 U241 1020 1 11 C201 C264C208 C265 C218 C223 C224 C231 C296C298 C202 C204 C206C207 C219 C232 C234 C258 C259 C263 C293 CR203 L261 R204 R281 R201 R202 R231 R232R233 SH202 13 25 37 1U201 U210 34 U211 3 4C525 C526 C527 C528 C529 C530 C531 C532 C533 C534 C535 C536 C537 C538 C544 C545 C546 C547 C549 C550 C551 C552 C553C555 C539 C540 C541 C542 C543 C548 C523 R509 R511 R510 UHF (403-470MHz) Main Board Bottom Side PCB No. 8404077G09