U2731B-NFN Atmel, U2731B-NFN Datasheet
U2731B-NFN
Specifications of U2731B-NFN
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U2731B-NFN Summary of contents
Page 1
... Electrostatic sensitive device. Observe precautions for handling. Description The U2731B is a monolithically integrated Digital Audio Broadcasting one-chip front end circuit manufactured using Atmel’s advanced UHF5S technology. Its functionality covers a gain-controlled RF amplifier with two selectable RF inputs, a gain-controlled RF mixer, a VCO which provides the LO signal for the RF mixers, either directly or ...
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... C1VCO 33 B2VCO VCO 34 B1VCO 35 C2VCO 42 OSCI 43 OSCO 5 Fractional-N FREF Programmable 13-bit counter 9-bit latch Simple two-wire bus interface/control 44 ADR U2731B 2 SAW1 SAW2 IFIN1 IFIN2 D/A D/A 4-bit latch 4-bit latch 4-bit latch Tristate Reference phase counter detector control 4-bit latch 3-bit latch ...
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... SCL 2 SDA 3 SWA 4 SWB 5 FREF 6 SWC 7 CAO CCO 8 CBO 9 GND 10 11 GND 12 RFA1 13 RFA2 RFB1 14 RFB2 15 CPRF 16 GND 17 SAW1 18 SAW2 SLI 21 WAGC 22 U2731B 44 ADR 43 OSCO 42 OSCI PLCK GND 36 GND 35 C2VC B1VCO 34 33 B2VCO 32 C1VC 31 GND 30 GND 29 IFOUT 28 CPIF 27 IFAGCIN1 26 IFAGCIN2 IFIN1 ...
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... Clock (simple two-wire bus) 2 SDA Data (simple two-wire bus) 3 SWA Switching output (open collector) 4 SWB Switching output (open collector) 5 FREF Reference frequency output (for U2731B) 6 SWC Switching output (open collector) 7 CAO Output of D/A converter A 8 CCO Output of D/A converter B 9 CBO ...
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... Address selection (simple two-wire bus) Functional Description 4671C–DAB–06/04 The U2731B represents a monolithically integrated front end IC designed for applica- tions in DAB receivers. It covers RF and IF signal processing, the PLL section and also supporting functions such as D/A converters or switching outputs. Two RF input ports offer the possibility of handling various input signals such as a down- converted L-band signal or band II and band III RF signals ...
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... Mixer, VCO and LO Divider RF AGC Voltage-generation Block U2731B 6 In order to support two different channels, two identical input buffers with balanced inputs (RFA1, RFA2; RFB1, RFB2) are integrated. By setting the two-wire bus bits M0 and M1 (see section “Simple Two-wire Bus Functions” on page 11), the active buffer can be selected ...
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... By means of the pins WAGC and SLI the current of this charge pump can be selected according to the following table: Table 2. Current of Charge Pump WAGC SLI HIGH LOW LOW LOW HIGH The function can be seen in Figure 12 on page 23. Charge-pump Current/µA X off 50 µA (slow mode) 190 µA (fast mode) U2731B 7 ...
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... PLL Part Reference Oscillator Reference Divider U2731B 8 The purpose of the PLL part is to perform a phase lock of the voltage-controlled RF oscillator to an on-chip crystal reference oscillator. This is achieved by means of a spe- cial phase-noise-shaping technique based on the fractional-N principle which is already used in Atmel's U2733B frequency synthesizer series. It concentrates the phase detec- tor's phase-noise contribution to the spectrum of the controlled VCO at frequency positions where it does not impair the quality of the received DAB signal ...
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... This behavior allows a change in the charge pump current without restricting the controlled VCO's frequency spectrum (N+k/ can be synthesized ref ref /SF VCO eff ref ref,eff and eff ref,eff U2731B = and , where SF is eff has to be pro- eff 9 ...
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... Switching Outputs D/A Converters U2731B 10 A high-gain amplifier (output pin: VD), which is implemented in order to construct a loop filter, as shown in the application circuit, can be switched off by means of the two-wire bus bit OS. An internal lock detector checks if the phase difference of the input signals of the phase detector is smaller than approximately 250 ns in seven subsequent comparisons ...
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... AS1 TA3 TA2 8 r TB3 TB2 4 r TC3 TC2 CA3 CA2 CB3 CB2 OS T TRI CC3 CC2 ) of the reference divider SF ref,eff U2731B LSB TA1 TA0 TB1 TB0 TC1 TC0 X X CA1 CA0 CB1 CB0 I100 I50 M1 M0 CC1 CC0 eff ref,eff ...
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... Simple Two-wire Bus Data Transfer U2731B 12 I50 and I100 define the charge pump current: Table 4. Current of Charge Pump I50 I100 LOW LOW HIGH LOW LOW HIGH HIGH HIGH Mi defines the operation mode: Table 5. Mode Selection LOW LOW X LOW HIGH X HIGH HIGH ...
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... Bus Description)”. Please note, that due to the two-wire bus specification, the MSB of a byte is transmitted first, the LSB last low hddat high sudat ACK A BYTE 1 ACK C BYTE 1 Start Stop t hdstat t t susta sustp ACK A BYTE 2 ACK ACK C BYTE 2 ACK STOP U2731B 13 ...
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... Address select voltage, pin 44 Switch output voltage; pins 3, 4 and 6 Switch output current PLCK output voltage, pin 41 PLCK output current, pin 41 Thermal Resistance Parameters Junction ambient (soldered on application board) Operating Range Parameters Supply voltage Ambient temperature range U2731B 14 Symbol Min -40 stg ...
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... S amb Pin Symbol 20, 25 S,min I S,max 12 (14) G V,RF 18, 19 SAW1, SAW2; 12 (14) NF DSB, dBc, 12 in,max,MIX (14, 15) 12 in,RF (14, 15) 12 (14) Z in,RF 18 out,SAW 18 TH,RF U2731B Min. Typ. Max. Unit Type* 8.0 8.5 9. -10 dBm A 70 260 MHz B 1 38,912 MHz D ± ...
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... Type means 100% tested 100% correlation tested Characterized on samples Design parameter Note: 1. The phase detector’s phase-noise contribution to the VCO’s frequency spectrum is determined by the operating frequency of the phase detector divided by 4 according to the fractional-N technique (regularly: 16 kHz). U2731B 25°C ...
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... VWAGC 2.0 High VWAGC 0.7 Low VSLI 2.0 High VSLI 0.7 Low SF 2048 32766 eff SF 144 2047 ref,eff ref v 50 ref,min v 300 ref,max 2.5 ref v 65 100 out,ref U2731B Unit Type µA A µA A µA A µA A µ kHz D MHz rms mV D rms ...
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... Type means 100% tested 100% correlation tested Characterized on samples Design parameter Note: 1. The phase detector’s phase-noise contribution to the VCO’s frequency spectrum is determined by the operating frequency of the phase detector divided by 4 according to the fractional-N technique (regularly: 16 kHz). U2731B 25°C ...
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... Antialiasing filter VAGCIF 3.3 8.5V 100p 10n 10n 10n 10n SAW 680nH 10n 10n 1n 220n 3.3 VAGCRF U2731B Unit Type* µs D µs D µs D µs D µs D µ AD-converter 4.7k 1.8k S+M X6922M filter WAGC SLI 8.5V 19 ...
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... Application Circuits of the Reference Oscillator U2731B 20 Figure 7. Oscillator Operation OSCI 68p 33p OSCO 18p Figure 8. Oscillator Overdriven Reference signal OSCI 1n 50 OSCO Reference divider Reference divider 4671C–DAB–06/04 ...
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... U2731B 76k 100n 100n 1n 100n RFA 1k 4.7k VAGCIF 3.3 47n 8.5V 100p 10n 10n 10n 3 220n 10n 10n 50 100 51 RFB VAGCRF O1SA U2731B IFAD 4.7k 1.8k IFIN 10n 50 WAGC SLI 8.5V 21 ...
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... Figure 10. RFAGC Voltage-generation Block Circuit SAW1 SAW2 BUF_IN Figure 11. IFAGC Voltage-generation Block Circuit V REF R AGC_THRESH IDA TCI D/A U2731B 22 V REF IDA TBI D/A AGC_BP AGC_RECT AGC_TP V REF R AGC_COMP AGC_THRESH IDA TAI D/A IFAMP IFMX IFAD VAGC IFAGC1 IFAGC2 CHARGE PUMP ...
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... C1VC B2VC B1VC C2VC (Example 16899 1120, f eff ref,eff spectrum analysis: HP7000) SPAN 10.00 kHz ST 3.050 sec V V Bias S = 17.92 MHz 200 mA, ref PD 10.00 dB/DIV CENTER 270.384 MHz SPAN 200.0 kHz RB 1.00 kHz VB 1.00 kHz ST 600.0 msec U2731B 23 ...
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... Ordering Information Extended Type Number U2731B–NFN U2731B–NFNG1 Package Information Package SSO44 Dimensions in mm 0.3 0 U2731B 24 Package Remarks SSO44 Tube SSO44 Taped and reeled 18.05 17.80 2.35 0.25 0.10 16 9.15 8.65 7.50 7.30 0.25 10.50 10.20 technical drawings according to DIN specifications 4671C– ...
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