SL1935 Single Chip Synthesized Zero IF Tuner DS5300 ISSUE 3.4 Features * * * * * * * * * * * April 2002 Ordering Information Single chip synthesised tuner solution for quadrature down conversion, L-band to Zero IF. DVB compliant, operating dynamic range -70 to -20dBm. Compatible with DSS and DVB variable symbol rate applications. Selectable baseband path, programmable through I2C bus. Excellent quadrature balance up to 30MHz baseband Excellent immunity to spurious second harmonic (RF and LO) mixing effects. Low oscillator phase noise and reradiation. High output referred linearity for low distortion and multi channel application. Integral fast mode compliant I2C bus controlled PLL frequency synthesiser, designed for high comparison frequencies and low phase noise performance. Buffered crystal output for clocking QPSK demodulator. ESD protection (Normal ESD handling procedures should be observed). Satellite receiver systems. * Data communications systems. XTALCAP XTAL SDA SCL BUFREF VCCD VCC RF RFB VCC IFIA IFIB VCC OFIA OFIB VEE IOUT ADD SL1935C/KG/NP1Q (Tape and Reel) Description The SL1935 is a complete single chip I2C bus controlled Zero IF tuner and operates from 950 to 2150MHz. It includes an on-board low phase noise PLL frequency synthesiser and low noise LNA/AGC. The SL1935 is intended primarily for application in digital satellite Network Interface Modules and performs the complete tuner function. The device contains all elements necessary, with the exception of local oscillator tuning network and crystal reference, to produce a high performance I(n-phase) & Q(uadrature) downconversion tuner function. Due to the high signal handling design the device does not require any front end tracking filters. The SL1935 includes selectable baseband signal paths, allowing application with two externally definable filter bandwidths, facilitating application in variable symbol rate and simulcast systems. The SL1935 is optimised to interface with the VP310 (ADC/QPSK/FEC) Satellite Channel Decoder, available from Zarlink Semiconductor and offers a full front end solution. Applications * SL1935C/KG/NP1P (Tubes) 1 18 36 19 Figure 1. Pin connections PUMP DRIVE PORT P0 VEE TANKS TANKSB VEE TANKV TANKVB VEE IFQA IFQB VCC OFQA OFQB VEE QOUT AGCCONT SL1935 RFB RF 8 9 AGCCONT 19 23 OFQA RF Section VCC 7,10,13,24 VCCD 6 VEE 16,21,27,30,33 22 OFQB AGC Sender RF section 26 IFQA PLL section 25 IFQB 20 QOUT BS 90deg 17 IOUT TANKV 29 TANKVB 28 Frequency Agile Phase Splitter VCOV TANKS 32 TANKSB 31 Divide by 2 11 IFIA 12 IFIB 0deg 14 OFIA VCOS 15 OFIB PLL Section VS BS 15 bit Programmab le Divider 36 PUMP Fpd Charge Pump 35 DRIVE SDA 3 I2C Bus Interface SCL 4 34 POR T P0 ADD 18 XTAL 2 XTALCAP 1 REF OSC Fpd/2 Reference Divider Figure 2. Block diagram 2 5 BUFREF Fcomp SL1935 Table 1. Quick Reference Data Characteristic Value 950 to 2150 Operating range -75 to -15 Input dynamic range 10 VSWR with input match Input NF 10 @ -70dBm operating sensitivity 15 @ -60dBm operating sensitivity +5 IPIP3 @ -20dBm operating sensitivity +20 IPIP2@ -20dBm operating sensitivity -5 IPP1dB@ -20dBm operating sensitivity 2.0 Baseband output limit voltage 0.2 Gain match up to 22MHz 0.7 Phase match up to 22MHz 1 Gain flatness up to 30MHz Local oscillator phase noise -80 SSB at 10kHz offset <-70 In band LO reradiation from RF input -55 LO second harmonic interference level at input level of -20dBm per carrier -35 LNA second harmonic interference level at input level of -25dBm per carrier 4 PLL maximum comparison frequency -152 PLL phase noise at phase detector Note: 6dB interstage filter loss assumed in external base band paths. dBm assumes 75 characteristic impedance. Functional Description General The SL1935 is a complete wideband direct conversion tuner incorporating an on board frequency synthesiser and LNA/AGC, optimised for application in digital satellite receiver systems. The device offers a highly integrated solution to a satellite tuner function, incorporating an I2C bus interface controller, a low phase noise PLL frequency synthesiser and all tuner analogue functionality. The analogue blocks include the reference oscillator, consisting of two independent oscillators, a phase splitter, RF preamplifier with AGC facility, channel mixers and baseband amplifiers incorporating two selectable baseband paths, allowing for two externally definable bandwidths. In this application two varactor tuned tanks, a reference crystal and baseband filtering components are required to complete the tuner system. A buffered crystal frequency output is available to clock the QPSK demodulator and powers up in the active state. The I2C bus interface controls the frequency synthesiser, the local oscillator, the baseband path selection, the buffered reference frequency output and an external switching port. Figure 2 shows the device block diagram and pin allocations are shown in Figure 1. Units MHz dBm dB dB dB dBm dBm dBm V dB deg dB dBc/Hz dBm dBc dBc MHz dBc/Hz Quadrature Downconverter Section In normal application the tuner IF frequency of typically 950 to 2150MHz is fed direct to the SL1935 RF input through an appropriate impedance match (Fig.16) and LNB switching. The input stage is optimised for both NF and signal handling. The signal handling of the front end is designed to offer immunity to input composite overload without the requirement of a tracking filter. RF input impedance is shown in Fig.3. The RF input amplifier feeds an AGC stage and provides system gain control. The system AGC gain range will guarantee an operating dynamic range of -70 to -20dBm. The AGC is controlled by the AGC sender and is optimised for S/N and S/I performance across the full dynamic range. Details of the AGC characteristics, variations in IIP3, IIP2, P1dB and NF are illustrated in Figs.4, 5, 6, 7, and 8 respectively. The required I and Q local oscillator frequencies for quadrature downconversion are generated by the onboard reference oscillators designated `VCOS' and `VCOV'. VCOS operates nominally from 1900 to 3000MHz and is then divided by two to provide 950 to 1500MHz. VCOV operates nominally from 1400 to 2200MHz. Only the oscillator selected via bit VS in the I2C data transmission is powered. 3 SL1935 Quadrature Downconverter Section - continued The oscillators share a common varactor line drive and both require an external varactor tuned resonator optimised for low phase noise performance. The recommended application circuit for the local oscillators is detailed in Fig.9 and the typical phase noise performance is detailed in Fig.10. The local oscillator frequency is coupled internally to the PLL frequency synthesiser programmable divider input. The mixer outputs are coupled to the baseband buffer amplifiers, providing for one of two selectable baseband outputs in each channel. The required output is selected by bit BS in the I2C bus transmission (Table 6). These outputs are fed off chip via ports `OPIA' and `OPIB' (`OPQA' and `OPQB'), then back on chip through ports `IPIA' and `IPIB' (`IPQA' and `IPQB'), allowing for the insertion of two independent user definable filter bandwidths. Each output provides a low impedance drive (Fig.11) and each input provides a high impedance load . An example filter for 30MS/s is detailed in Fig.13. Both path gains are nominally equal. NB 6dB insertion loss is assumed in each channel, however a different pot down ratio may be applied. Each baseband path is then multiplexed to the final baseband amplifier stage, providing further gain and a low impedance output drive. The nominal output load test condition is detailed in Fig.14. PLL Frequency Synthesiser Section The PLL frequency synthesiser section contains all the elements necessary, with the exception of a reference frequency source and a loop filter to control the selected oscillator to produce a complete PLL frequency synthesised source. The device, produced using high speed logic, allows for operation with a high comparison frequency and enables the generation of a loop with excellent phase noise performance. The LO signal from the selected oscillator drives from the phase splitter into an internal preamplifier, providing gain and reverse isolation from the divider signals. The output of the preamplifier interfaces directly with the 15-bit fully programmable divider. The programmable divider has MN+A architecture, the dual modulus prescaler is 16/17, the A counter is 4-bits and the M counter is 11-bits. The output of the programmable divider is fed to the phase comparator and compared in both phase and frequency domains to the comparison frequency. This frequency is derived from either the on board crystal controlled oscillator or from an external reference source. In both cases the reference frequency is divided down to the comparison frequency by the reference divider, programmable into 1 of 29 ratios and detailed in Table 3. The typical application for the crystal oscillator is shown in Fig.15. 4 The output of the phase detector feeds a charge pump and a loop amplifier. When used with an external loop filter and a high voltage transistor it integrates the current pulses into the varactor line voltage used to control the selected oscillator. The programmable divider output Fpd divided by two and the reference divider output Fcomp are switched to port P0 by programming the device into test mode. Test modes are detailed in Table 4. The crystal reference frequency can be switched to the BUFREF output by bit RE as detailed in Table 7. Programming The SL1935 is controlled by an I2C data bus and is compatible with both standard and fast mode formats. Data and Clock are fed on the SDA and SCL lines respectively as defined by the I2C bus format. The device can either accept data (write mode) or send data (read mode). The LSB of the address byte (R/W) sets the device into write mode if it is low and read mode if it is high. Tables 9a and 9b detail the format of the data. The SL1935 may be programmed to respond to several addresses and enables the use of more than one device in an I2C bus system. Table 9c details the how the address is selected by applying a voltage to the `ADD' input. When the device receives a valid address byte, it pulls the SDA line low during the acknowledge period and during following acknowledge periods after further data bytes are received. When the device is programmed into read mode, the controller accepting the data must pull the SDA line low during all status byte acknowledge periods to read another status byte. If the controller fails to pull the SDA line low during this period, the device generates an internal `STOP' condition which inhibits further reading. Write mode Bytes 2 and 3 contain frequency information bits 214to 20 inclusive (Table 9). Byte 4 controls the synthesiser reference divider ratio (Table 3) and the charge pump setting (Table 5). Byte 5 controls test modes (Table 4), baseband filter path select BS (Table 6), local oscillator select VS (Table 8), buffered crystal reference output select RE (Table 7) and the output port P0. After reception and acknowledgment of a correct address (byte 1), the first bit of the following byte determines whether the byte is interpreted as byte 2 or 4, a logic `0' indicates byte 2 and a logic `1' indicates byte 4. Having interpreted this byte as either byte 2 or 4, the following byte will be interpreted as byte 3 or 5 respectively. After receiving two complete data bytes, additional data bytes may be entered and byte interpretation follows the same procedure without readdressing the device. The procedure continues until a `STOP' condition is received. SL1935 The STOP condition can be generated after any data byte, if however it occurs during a byte transmission, the previous byte data is retained. To facilitate smooth fine tuning, the frequency data bytes are only accepted by the device after all 15 bits of frequency data have been received, or after the generation of a STOP condition. Read mode When the device is in read mode, the status byte read from the device takes the form shown in Table 9b. Bit 1 (POR) is the power-on reset indicator, and this is set to a logic `1' if the Vccd supply to the device has dropped below 3V (at 25oC),e.g. when the device is initially turned ON. The POR is reset to `0' when the read sequence is terminated by a STOP command. When POR is set high this indicates that the programmed information may have been corrupted and the device reset to the power up condition. Bit 2 (FL) indicates whether the synthesiser is phase locked, a logic `1' is present if the device is locked, and a logic `0' if the device is unlocked. Table 2. Programmable Features Programmable features Function Function as described above Function as described above. Function as described above. Function as described above. The charge pump current can be programmed by bits C1 & C0 (Table 5). The test modes are defined by bits T2 - T0 as described in Table 4. The general purpose port can be programmed by bit P0; Logic `1' = on Logic `0' = off (high impedance) The buffered crystal reference frequency can be switched to the BUFREF Buffered crystal reference output, output by bit RE as described in Table 7. The BUFREF output defaults to BUFREF the `ON' condition at device power up. The typical key performance data at Vcc = 5V and +25oC ambient are detailed in Table 1. Synthesiser programmable divider Reference programmable divider Baseband filter path select Local oscillator select Charge pump current Test mode General purpose port, P0 Table 3. Reference division ratios R4 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 R3 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 R2 0 0 0 0 1 1 1 1 0 0 0 0 1 1 1 1 0 0 0 0 1 1 1 1 0 0 0 0 1 1 1 1 R1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 R0 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 Ratio 2 4 8 16 32 64 128 256 Illegal state 5 10 20 40 80 160 320 Illegal state 6 12 24 48 96 192 384 Illegal state 7 14 28 56 112 224 448 5 SL1935 Table 4. Test modes T2 0 0 0 0 1 1 1 1 T1 0 0 1 1 0 0 1 1 Test mode description Normal operation Charge pump sink* (status byte FL set to logic '0') Charge pump source* (status byte FL set to logic '0') Charge pump disabled* (status byte FL set to logic '1') Normal operation and port P0 = Fpd/2 Charge pump sink* (status byte FL set to logic '0'. Port P0 = Fcomp) Charge pump source* (status byte FL set to logic '0'. Port P0 = Fcomp) Charge pump disabled* (status byte FL set to logic '1'. Port P0 = Fcomp) T0 0 1 0 1 0 1 0 1 Note: * Clocks need to be present on crystal and RF inputs to enable charge pump test modes and to toggle status byte bit FL. Table 5. Charge pump current C1 C0 0 0 1 1 0 1 0 1 Current in A min typ max +-116 +-155 +-194 +-247 +-330 +-412 +-517 +-690 +-862 +-1087 +-1450 +-1812 Table 6. Baseband path select BS 0 1 Path Selected I Channel Q Channel Filter drive Baseband Filter drive Baseband output amp input output amp input IFQB IFIB OFQB OFIB IFQA IFIA OFQA OFIA Table 7. Buffered crystal reference output select RE 0 1 BUFREF output Disabled, high impedance Enabled Table 8. Local oscillator select VS 0 1 6 Local oscillator selected VCOV VCOS SL1935 Table 9a. Write data format (MSB is transmitted first) Address Programmable divider Programmable divider Control data Control data MSB 1 0 1 214 0 213 0 212 0 211 MA1 210 MA0 29 LSB 0 28 A A Byte 1 Byte 2 27 26 25 24 23 22 21 20 A Byte 3 1 T2 C1 T1 C0 T0 R4 VS R3 BS R2 0 R1 RE R0 P0 A A Byte 4 Byte 5 MA1 0 MA0 0 LSB 1 0 A A Table 9b. Read data format (MSB is transmitted first) MSB 1 POR Address Status Byte 1 FL 0 0 0 0 0 0 Byte 1 Byte 2 Table 9c. Address selection MA1 0 0 1 1 Address input voltage level 0 - 0.1 Vcc Open circuit 0.4 Vcc - 0.6 Vcc* 0.9 Vcc - Vcc MA0 0 1 0 1 Note: * Programmed by connecting a 30k resistor between pin and Vcc Key to Tables 9a to 9c A ......................................... Acknowledge bit MA1, MA0 ........................... Variable address bits (Table 9c) 214 to 20................................ Programmable division ratio control bits C1 to C0 .............................. Charge pump current select (Table 5) R4 to R0 .............................. Reference division ratio select (Table 3) T2 to T0 .............................. Test modes control bits (Table 4) BS ....................................... Baseband path select (Table 6) VS ....................................... Local oscillator select (Table 8) RE ....................................... Buffered crystal reference output enable (Table 7) P0 ....................................... P0 port output state POR .................................... Power on reset indicator FL ........................................ Phase lock flag +j1 +j2 +j0.5 +j0.2 0 +j5 0.2 0.5 2 1 Marker Freq (MHz) 950 1 1400 2 1600 3 4 2150 5 X Z real Z imag -100 64 -75 40 -65 32 23 -45 --j5 --j0.2 X 4 X X 3 Normalised to 75 1 --j2 --j0.5 START 950MHz X 2 --j1 STOP 2150MHz Figure 3. RF input impedance (typical) 7 SL1935 90 System gain (dB) assuming 6dB interstage filter loss 80 70 70dB minimum, AGC < 0.75V 60 50 40 30 20 20dB maximum, AGC > 4.25V 10 0 0 0.5 1 1.5 2 2.5 3 AGCCONT Voltage (V) 3.5 4 4.5 5 Figure 4. AGC characteristic (typical) System input referred IP3 (dBuV) 120 110 100 90 80 70 60 20 25 30 35 40 45 50 55 60 65 70 System gain (dB) assuming 6dB interstage filter loss Figure 5. Variation in IIP3 with system gain (typical) System input referred IP2 (dBuV) 170 160 Baseband dominated IP2 150 140 130 LNA dominated IP2 120 110 100 20 25 30 35 40 45 50 55 System gain (dB) assuming 6dB interstage filter loss Figure 6. Variation in IIP2 with system gain (typical) 8 60 65 70 SL1935 Converter input referred P1dB (dBuV) 110 105 100 95 90 85 80 75 70 65 60 -10 25 10 0 5 30 35 15 20 Converter gain seting (dB) from RF inputs OFIA/OFQA or OFIB/OFQB outputs -5 40 45 Figure 7. Variation in P1dB with converter gain (typical) 60 Noise figure (dB) 50 40 30 20 10 0 20 25 30 35 40 45 50 55 60 System gain (dB) assuming 6dB interstage filter loss 65 70 75 80 Figure 8. Variation in NF with system gain (typical) BB837 4mm STRIPLINE 6 Tanks 1k "vcos" 2k BB837 4mm STRIPLINE 7 Tanksb Vcnt BB831 10mm STRIPLINE 9 Tankv "vcov" 2k 1k BB831 10mm STRIPLINE 10 Tankvb NOTE: Stripline width = 0.44mm (dimensions are approximate) Figure 9. Local oscillator application circuit 9 SL1935 LO Frequency (MHz) 900 1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000 2100 -70 Phase noise @ 10kHz offset (dBc/Hz) -72 vcos enabled -74 vcov enabled -76 -78 -80 -82 -84 -86 Conditions: Loop filter as per standard application shown in Figure 21 Charge pump = 130uA Fcomp = 65.5kHz or 125kHz -88 -90 Figure 10. Local oscillator phase noise variation with frequency (typical) +j1 +j0.5 +j2 3 +j0.2 0 4 x x +j5 2x 1 0.5 0.2 x 2 1 Marker 1 2 3 4 5 Freq (MHz) 1 10 20 30 Z real 17 18 22 33 Z imag 0 19 38 60 --j5 --j0.2 --j2 --j0.5 START 1MHz Normalised to 50 STOP 30MHz --j1 Figure 11. Converter output impedance; OFIA, OFIB, OFQA, OFQB (typical) +j1 +j0.5 +j2 +j0.2 +j5 Marker 1 2 3 4 X4 0 0.2 X3 X2 X1 0.5 1 2 5 X Z real 9.5 10.0 10.6 12.6 --j5 --j0.2 --j2 --j0.5 START 100kHz Normalised to 50 Freq (MHz) 0.1 10 20 30 --j1 STOP 30MHz Figure 12. Baseband output impedance; IOUT, QOUT (typical) 10 Z imag -2.0 1.3 3.3 5.5 SL1935 100nF OFIA/OFIB OFQA/OFQB 100nF 1k IFIA/IFIB IFQA/IFQB 1k 3.9pF Figure 13. Example baseband interstage filter for 30MS/s 220nF 100 1k 15pF Figure 14. Nominal baseband output load test condition 1 XTALCAP 150pF 2 XTAL 82pF 4MHz Figure 15. Crystal oscillator application (typical) 11 SL1935 1pF 100pF 8 RFIN 9 2.2pF RF RFB SL1935 33 100pF Figure 16. Input matching network Table 10. Electrical Characteristics Test conditions (unless otherwise stated); Tamb = -20o to +80oC, Vee= 0V, Vcc =Vccd = 5V+-5%. These characteristics are guaranteed by either production test or design. They apply within the specified ambient temperature and supply voltage unless otherwise stated. Characteristic Value Pin Min Supply current RF input operating frequency SYSTEM 6,7,10 13,24 8,9 130 175 mA 2150 MHz 10 15 Variation in system NF with gain adjust System input referred IP2 121 Variation in system input referred IP2 with operating sensitivity System input referred IP3 112 Variation in system input referred IP3 with operating sensitivity Max 950 System noise figure DSB Units Typ 140 12 17 -1 Conditions VCCD (PLL) and VCC All system specification items should be read in conjunction with Note 2 dB At -70dBm operating sensitivity dB At -60dBm operating sensitivity dB/dB Above -60dBm operating sensitivity, (Fig.7) dBV At -20dBm operating sensitivity, see Notes 3 and 4 (Fig.6) dBV At -20dBm operating sensitivity, see Note 5 (Fig.5) Continued 12 SL1935 Table 10. Electrical Characteristics (Continued) Characteristic Value Pin Min Typ Units dBm dBm dB dB Note 6 AGCCONT = 0.75V AGCCONT = 4.25V Within RF band 950-2150MHz -20C to +80C Interstage filter (Fig.13) Interstage filter (Fig.13) Interstage filter (Fig.13) System dynamic range -70 -20 System gain roll off System gain variation with temperature System I Q gain match System I Q phase balance System I and Q channel in band ripple System baseband path gain match LO second harmonic interference level LNA second harmonic interference level Synthesiser and other spurii on I and Q outputs 3 2 17,20 17,20 17,20 8,9 CONVERTER Converter input impedance Converter input return loss System input referred P1dB 8,9 8,9 Converter output impedance, OFIA, 14,15 OFIB, OPQA and OPQB. 22,23 Conver ter output leakage to unselected output, OFIA, OFIB, OPQA and OPQB. Oscillator VCOS operating range 31,32 Oscillator VCOV operating range Local oscillator SSB phase noise AGCONT input current -1 -3 +1 +3 1 dB deg dB -1 +1 dB -50 dBc Note 8. -35 dBc Note 9. 76 17,20 In band leakage to RF input 28,29 -60 75 8 102 25 50 1900 3000 1450 -150 dBV Within 0-100MHz band under all gain settings, RF input set to deliver 108dBV on output dBm Within RF band 950-2150MHz. Note 11. dB With input matching (Fig.16) dBV Converter gain =-5dBm (to OFIA/ OPQA, OFIB/OPQB outputs. Fig.7) 0.1 to 30MHz (Fig.11) dBc -26 -78 19 Giving LO = 950 to 1500MHz (Application as in Fig.9) 2150 MHz (Application as in Fig.9) dBc/Hz @10kHz offset, PLL loop bw < 1kHz Application is measured at baseband output frequency of 10MHz (Fig.10). 150 A The baseband inputs must be externally ac coupled 0.1- 30MHz bandwidth 11,12 25,26 17,20 5 -40 k pF dBc 17,20 20 10 17,20 17,20 Relative to selected output MHz BASEBAND AMPLIFIERS Baseband input impedance, IFIA, IFIB, IFQA And IFQB. Resistance Capacitance Baseband unselected input leakage to output Baseband amplifier output impedance Baseband output limiting Baseband bandwidth 1dB Baseband output roll-off Conditions Max 2.0 40 6 Relative to selected input. Vp-p Level at hard clipping (load as Fig.14) MHz (Load as Fig.14) dB/oct Above 3dB point, no load Continued 13 SL1935 Table 10. Electrical Characteristics (Continued) Characteristic Value Pin Min SYNTHESISER SDA,SCL Input high voltage Input low voltage Input high current Input low current Leakage current Hysterysis SDA output voltage SCL clock rate Charge pump output current Charge pump output leakage Charge pump drive output current Crystal frequency Recommended crystal series resistance External reference input frequency External reference drive level Phase detector comparison frequency Equivalent phase noise at phase detector Local oscillator programmable divider division ratio Reference division ratio Output port P0 Sink current Leakage current BUFREF output Output amplitude Output impedance Address select Input high curent Input low current Typ Units I2C 'fast mode' compliant 3,4 3 0 5.5 1.5 10 V V A A 10 A V V V kHz -10 0.4 0.4 0.6 400 3 4 36 36 35 1,2 Conditions Max +-3 +-10 0.5 2 10 20 200 2 2 20 2 0.2 0.5 4 nA mA MHz Vcc = Vee = 0V Isink = 3mA Isink = 6mA Vpin36 = 2V. (Table 5) Vpin36 = 2V Vpin35 = 0.7V (Fig.15 for application) 4MHz parallel resonant crystal MHz Sinewave coupled via 10nF blocking capacitor Vpp Sinewave coupled via 10nF blocking capacitor MHz dBc/Hz SSB within loop bandwidth, all comparison frequencies -152 32767 240 34 2 10 mA A 5 0.25 Input voltage = Vcc Input voltage = Vee 0.35 250 0.45 Vpp 1 -0.5 mA mA 18 (Table 3) (Note 7) Vport = 0.7 Vport = Vcc AC coupled. (Note 10.) Enabled by bit RE = 1 and default state on power-up. (Table 9c) Vin = Vcc Vin = Vee Notes to Table 10 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 14 All power levels are referred to 75, and 0dBm = 109dBV. System specifications refer to total cascaded system of converter/AGC stage and baseband amplifier stagewith nominal 6dB pad as interstage filter and load impedance as detailed in Figure 14. Baseband dominated IP2. AGC set for 20dB system gain with two tones for intermodulation test at fc+146and fc+155MHz at 100dBV generating output intermodulation spur at 9MHz. 30MHz 3dB bandwidthinterstage filter included. LNA dominated IP2. AGC set for 20dB system gain with two tones for intermodulation test at fc+146 and2*fc+155 MHz at 100dBV generating output intermodulation spur at 9MHz. 30MHz 3dB bandwidthinterstage filter included. AGC set for 20dB system gain with two tones for intermodulation test at fc+110 and fc+211MHz at 100dBVgenerating output intermodulation spur at 9MHz. 30MHz 3dB bandwidth interstage filter included. Dynamic range assuming termination as detailed in Figure 14, and including 6 dB interstage filter insertion loss, delivering 700mVp-p at baseband outputs (pins 17,20). AGC monotonic from Vee to Vcc (Fig.4). Port powers up in high impedance state. The level of 2.01GHz downconverted to baseband relative to 1.01GHz with the oscillator tuned to 1GHz,measured with no input pre-filtering. The level of second harmonic of 1.01GHz input at -25dBm downconverted to baseband relative to 2.01GHz at-40 dBm with the oscillator tuned to 2GHz, measured with no input pre-filtering. If the BUFREF output is not used it should be left open circuit or connected to Vccd, and disabled by settingRE = `0'. This parameter is very application dependant. With good RF isolation <-60dBm can be achieved. SL1935 VCC VREF RF 8 5K RFB 9 AGCCONT RF inputs 19 30K AGC input VREF2 1K 1K TANK OFIA OFIB OFQA OFQB TANKB Oscillator inputs (pins 28, 29 and 31, 32) IFIA IFIB IFQA IFQB BIAS Baseband amplifier inputs (pins 11, 12, 25 and 23) Converter outputs (pins 14, 15, 22 and 23) IOUT and QOUT Baseband outputs (pins 17 and 20) Figure 17. Input and output interface circuits (RF section) 15 SL1935 Vccd Vccd 36 PUMP XTAL XTALCAP 2 1 300 35 DRIVE Loop amplifier Reference oscillator Vccd Vccd 60K 3K 47K ADD SCL/SDA ACK ] 18 20K ] On SDA only ADD input SDA/SCL (pins 3 and 4) Vccd P0 34 5 BUFREF ENABLE/ DISABLE Output port BUFREF output Figure 18. Input and output interface circuits (PLL section) 16 SL1935 Table 11. Absolute Maximum Ratings (All voltages referred to Vee at 0V and Vcc = Vccd) Characteristic Supply voltage SDA, SCL DC offsets All I/O port DC offsets Por t P0 current Storage temperature Junction temperature Package thermal resistance, chip to case Package thermal resistance, chip to ambient Power consumption at 5.25V ESD protection Min Max Units -0.3 -0.3 -0.3 7 6 Vcc+0.3 10 150 150 20 V V V mA oC oC oC/W 77 oC/W 919 mW kV -55 3.5 Conditions Vcc = Vee to 5.25V Mil-std 883 method 3015 cat1 SL1935 Demo Board The demo board contains an SL1935 I2C bus controlled Zero IF tuner IC, plus all components necessary to demonstrate operation of the SL1935. The schematic and PCB layout of the board are shown in Figures 19, 20 and 21. Supplies The board must be provided with the following supplies: 5V for the synthesiser section (5VD) 5V for the converter and baseband sections (5V) 30V for the varactor line (30V) The supply connector is a 5 pin 0.1" pin header. The order of connections is 5V - GND - 30V - GND - 5V. I2C bus connections The board is provided with a RJ11 I2C bus connector which feeds directly to the synthesiser. This connects to a standard 4 way cable. Operating instructions 1. Software. Use the Zarlink Semiconductor synthesiser software. Pull down the `Device' menu, then select the `SL1935'. It is suggested that the charge pump is set to 130uA with a reference divider ratio of 32. These settings give a small loop bandwidth (i.e. 100's Hz), which allows detailed phase noise measurements of the oscillators to be taken if desired. 2. VCO control. The two VCO's are selected by toggling the oscillator switch below the two oscillators on the main software block diagram. This switch programs bit VS of the I2C data (see Tables 8 and 9a to 9c). VCOS oscillates at twice the LO frequency (lower band) and is then divided by two to provide the required LO frequency in the range 950MHz to 1500MHz (approximately). VCOV oscillates at the LO frequency (upper band) in the range 1500MHz to 2150MHz (approximately). 3. Baseband path select. The SL1935 has two filter paths selected by programming bit BS of the I2C data (see Tables 6 and 9a to 9c). The value of BS is changed by toggling the switch position to the left of `Filter A' and `Filter B' on the main software block diagram. 4. AGC control. The conversion gain of the SL1935 is set by the voltage applied to the AGCCONT input. On the demo board this is controlled by the potential divider labelled `AGC ADJ' which varies the AGCCONT input from 0V to Vcc. CAUTION: Care should be taken to ensure the chip is powered ON if the board is modified to accept an external AGC input voltage. Damage to the device may result if this is not complied with as a result of the IC powering itself up via the AGCCONT input ESD protection diode. It is recommended that a low current limit is set on any external AGC voltage source used. 5. Free running the VCO's. Select the required VCO as detailed in (2) above. Program an LO frequency which is above the maximum capability of the oscillator. 3GHz is suggested. Under this condition the varactor control voltage is pumped to its maximum value, ie to the top of the band. The oscillator frequency can now be manually tuned by varying the 30V supply. 17 SL1935 19. View Figure 19. Top view 18 SL1935 Figure 20. Bottom view 19 CN8 C26 68pF C27 15nF TP6 5 4 3 2 1 R18 13K R19 13K C2 82pF I2C C3 150pF 5VD 1 2 TP1 SK1 RF IN SDA 5V0 GND SCL RFinA 3 3 4 5 6 4 TP2 TP3 5VD C40 100pF 5V C39 100pF RFinA 1nF 5V 1nF R7 C6 C7 C8 IOUT R1 1K R2 QOUT C11 3p9 R3 1K R4 1K 8 9 75R SK3 6 7 C5 SK2 I OUT 5 10 100nF 11 100nF 12 5V 13 C9 100nF 14 C10 100nF 15 1K SDA PORT P0 SCL Vee TANKSa BUFref TANKSb VccD Vee Vcc RFin TANKVa RFinB TANKVb Vee Vcc IFQA IFIa Q OUT of IFIb IFQB Vcc Vcc OFIb 17 18 C13 220nF DRIVE XTAL 16 C12 3p9 PUMP XTALCAP OFIa OFQA OFQB Vee Vee Iout Qout ADD C28 100nF AGC cont + C30 22uF 30V 36 TR1 BCW31 TP5 35 R17 1K R16 1K C31 100nF 34 P0 C32 100pF D1 BB837 5V 33 L1 32 R23 2K L2 31 D3 30 D4 5VD BB831 100nF 25 C23 5V 24 100nF 23 C22 100nF 22 C21 100nF R21 620R R15 2K7 TP8 AGC R14 1K AGC RV1 5K D5 PORT 0 R13 1K 21 R22 620R OFQB 20 C19 3p9 C18 220nF 19 SL1935 C36 100nF C35 100pF 5V GND 26 C24 C34 100pF R24 2K L4 28 C33 100pF D2 BB837 L3 29 27 BB831 R11 1K R12 1K C20 3p9 1 2 AGC TP4 R5 100R C16 10nF QOUT IOUT C14 C29 100pF C25 2n2 IC1 XL1 4MHz CN7 5VD DC POWER R20 22K R6 1K TP7 R10 100R R9 1K C17 15pF 15pF Figure 21. P0 JP1 C37 100pF C38 + 22uF SL1935 20 30V SL1935 Purchase of Mitel Semiconductor I2C components conveys a licence under the Phillips I2C Patent rights to use these components in an I2C system,provided that the system conforms to the I 2C Standard Specification as defined by Phillips. 21 SL1935 22 For more information about all Zarlink products visit our Web Site at www.zarlink.com Information relating to products and services furnished herein by Zarlink Semiconductor Inc. trading as Zarlink Semiconductor or its subsidiaries (collectively "Zarlink") is believed to be reliable. However, Zarlink assumes no liability for errors that may appear in this publication, or for liability otherwise arising from the application or use of any such information, product or service or for any infringement of patents or other intellectual property rights owned by third parties which may result from such application or use. Neither the supply of such information or purchase of product or service conveys any license, either express or implied, under patents or other intellectual property rights owned by Zarlink or licensed from third parties by Zarlink, whatsoever. Purchasers of products are also hereby notified that the use of product in certain ways or in combination with Zarlink, or non-Zarlink furnished goods or services may infringe patents or other intellectual property rights owned by Zarlink. This publication is issued to provide information only and (unless agreed by Zarlink in writing) may not be used, applied or reproduced for any purpose nor form part of any order or contract nor to be regarded as a representation relating to the products or services concerned. The products, their specifications, services and other information appearing in this publication are subject to change by Zarlink without notice. No warranty or guarantee express or implied is made regarding the capability, performance or suitability of any product or service. Information concerning possible methods of use is provided as a guide only and does not constitute any guarantee that such methods of use will be satisfactory in a specific piece of equipment. It is the user's responsibility to fully determine the performance and suitability of any equipment using such information and to ensure that any publication or data used is up to date and has not been superseded. Manufacturing does not necessarily include testing of all functions or parameters. These products are not suitable for use in any medical products whose failure to perform may result in significant injury or death to the user. All products and materials are sold and services provided subject to Zarlink's conditions of sale which are available on request. Purchase of Zarlink s I2C components conveys a licence under the Philips I2C Patent rights to use these components in and I2C System, provided that the system conforms to the I2C Standard Specification as defined by Philips. Zarlink and the Zarlink Semiconductor logo are trademarks of Zarlink Semiconductor Inc. Copyright 2001, Zarlink Semiconductor Inc. All Rights Reserved. TECHNICAL DOCUMENTATION - NOT FOR RESALE