 |
전자부품 데이터시트 검색엔진 |
|
|
전자부품 데이터시트 검색엔진 |
|
TUA6030 데이터시트(PDF) 20 Page - Infineon Technologies AG |
|
||||||||||||||||||||||||||||||
TUA6030 데이터시트(HTML) 20 Page - Infineon Technologies AG |
|
|
20 / 49 page  Functional Description 3 - 20 TUA6030, TUA6032 Wireless Components Specification, July 2001 3.4 Circuit Description 3.4.1 Mixer-Oscillator block The mixer-oscillator block includes three balanced mixers (one mixer with an unbalanced high-impedance input and two mixers with a balanced low-imped- ance input), two 2-pin asymmetrical oscillators for the LOW and the MID band, one 4-pin symmetrical oscillator for the HIGH band, an IF amplifier, a reference voltage, and a band switch. Filters between tuner input and IC separate the TV frequency signals into three bands. The band switching in the tuner front-end is done by using three PNP port outputs. In the selected band the signal passes a tuner input stage with a MOSFET amplifier, a double-tuned bandpass filter and is then fed to the mixer input of the IC which has in case of LOW band a high-impedance input and in case of MID or HIGH band a low-impedance input. The input signal is mixed there with the signal from the activated on chip oscillator to the IF frequency which is filtered out at the balanced mixer output pair by means of a parallel tuned circuit. The following IF amplifier is capacitively coupled to the mixer out- puts and has a low output impedance to drive the SAW filter directly. 3.4.2 PLL block The oscillator signal is internally DC-coupled as a differential signal to the pro- grammable divider inputs. The signal subsequently passes through a program- mable divider with ratio N = 256 through 32767 and is then compared in a digital frequency/phase detector with a reference frequency fref = 31.25, 50, 62.5 or 166.7 kHz. This frequency is derived from an unbalanced, low-impedance 4 MHz crystal oscillator (pin XTAL) divided by 128, 80,64 or 24. The reference fre- quencies will be different with a quartz other than 4 MHz. The phase detector has two outputs which drive two current sources of a charge pump. If the negative edge of the divided VCO signal appears prior to the neg- ative edge of the reference signal, the positive current source pulses for the duration of the phase difference. In the reverse case the negative current source pulses. If the two signals are in phase, the charge pump output (CP) goes into the high-impedance state (PLL is locked). An active low-pass filter integrates the current pulses to generate the tuning voltage for the VCO (inter- nal amplifier, external pull-up resistor at VT and external RC circuitry). The charge pump output is also switched into the high-impedance state if the control bits T2, T1,T0 = 0, 1, 0. Here it should be noted, however, that the tuning volt- age can alter over a long period in the high impedance state as a result of self discharge in the peripheral circuity. VT may be switched off by the control bit OS to allow external adjustments. If the VCO is not oscillating the PLL locks to a tuning voltage of 33V (VTH). |
유사한 부품 번호 - TUA6030 |
|
유사한 설명 - TUA6030 |
|
|
링크 URL |
| 개인정보취급방침 |
| ALLDATASHEET.CO.KR |
| ALLDATASHEET 가 귀하에 도움이 되셨나요? [ DONATE ] |
Alldatasheet는? | 광고문의 | 운영자에게 연락하기 | 개인정보취급방침 | 링크교환 | 제조사별 검색 All Rights Reserved©Alldatasheet.com |
| Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
|
Family Site : ic2ic.com |
icmetro.com |
Korean ▼
English
Chinese
German
Japanese
Russian
Korean
Spanish
French
Italian
Portuguese
Polish
Vietnamese
Indian
Mexican
British
New Zealand
