数据搜索系统,热门电子元器件搜索 |
|
TEA0675 数据表(PDF) 11 Page - NXP Semiconductors |
|
TEA0675 数据表(HTML) 11 Page - NXP Semiconductors |
11 / 32 page 1996 Jun 07 11 Philips Semiconductors Preliminary specification Dual Dolby* B-type noise reduction circuit for playback applications TEA0675 Description of the principle timing diagram for AMS-scan mode without initial input signal (see Fig.5) handbook, full pagewidth MED625 output signal to microprocessor 4.5 V VAMSEQ time threshold upper threshold (hysteresis) Vt VREF level threshold Vl Vin tr: rise time td: delay time tb: burst time tp: pause time tf: fall time Vl: voltage at level detector input pin 3 (CONTRA) Vt: voltage at time detector input pin 22 (CONTRB) t t t t AMS on tr td tf tb<tr tp<td t0 t3 t4 t5 t6 t7 t8 t9 t10 t11 t12 t13 t14 t15 Fig.5 AMS-scan mode without initial input signal. By activating AMS-scan mode, the AMS output level directly indicates whether the input level corresponds to a pause level (VAMSEQ = LOW) or not (VAMSEQ = HIGH). At t0 the AMS-scan mode is activated. Without a signal at Vin, the following initial procedure runs until the AMS output changes to LOW level: due to no signal at Vin the voltage at the level detector input VI (pin 3, CONTRA) remains below the level threshold and the second time constant will be discharged (time detector input Vt). When Vt passes the time threshold level, the time detector output changes to LOW level. Now the initial procedure is completed. If a signal burst appears at t3, the level detector input voltage rises immediately and causes its output to charge the second time constant, which supplies the input voltage Vt for the time detector. When Vt passes the upper threshold level after the rise time tr (at t4), the AMS output changes to HIGH. If the signal burst ends at t5 the level detector input VI falls to its LOW level. When passing the level threshold at t6, the discharging of the second time constant begins. Now the circuit measures the delay time td, which is externally fixed by a resistor and defines the length of a pause to be detected. If no signal appears at Vin within the time interval td, the time detector output switches the AMS output to LOW level at t7. If a plop noise pulse appears at Vin (t8) with a pulse width less than the rise time tr >tb, the plop noise will not be detected as music. The AMS output remains LOW. Similarly the system handles ‘no music pulses’ tp: when music appears at t11 with a small interruption at t13, this interruption will not affect the AMS output for tp <td. |
类似零件编号 - TEA0675 |
|
类似说明 - TEA0675 |
|
|
链接网址 |
隐私政策 |
ALLDATASHEETCN.COM |
ALLDATASHEET是否为您带来帮助? [ DONATE ] |
关于 Alldatasheet | 广告服务 | 联系我们 | 隐私政策 | 链接交换 | 制造商名单 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 |