- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄30714 > LA1781M AM/FM, AUDIO SINGLE CHIP RECEIVER, PQFP64 PDF資料下載
參數(shù)資料
| 型號： | LA1781M |
| 元件分類： | 接收器 |
| 英文描述： | AM/FM, AUDIO SINGLE CHIP RECEIVER, PQFP64 |
| 封裝： | 14 X 14 MM, QIP-64 |
| 文件頁數(shù)： | 21/48頁 |
| 文件大?。?/td> | 508K |
| 代理商： | LA1781M |
第1頁第2頁第3頁第4頁第5頁第6頁第7頁第8頁第9頁第10頁第11頁第12頁第13頁第14頁第15頁第16頁第17頁第18頁第19頁第20頁當(dāng)前第21頁第22頁第23頁第24頁第25頁第26頁第27頁第28頁第29頁第30頁第31頁第32頁第33頁第34頁第35頁第36頁第37頁第38頁第39頁第40頁第41頁第42頁第43頁第44頁第45頁第46頁第47頁第48頁
LA1781M
No.6038-28/48
Transient response characteristics during automatic tuning
The transient characteristics for SD and IF count buffer on/off operation are determined by the time constants of the
RC circuits attached to the following pins.
(1) Muting time constant : pin 33
(2) S-meter time constant : pin 24
(3) AFC time constant : pin 34
There are two points that require consideration when using fast tuning.
(1) The SD time constant due to the S-meter time constant
Since the current I24 (pin 24) varies with the field strength, the time constant also changes. There is no hysteresis in
the comparator.
If C24 is made smaller and the pin 24 voltage is used for the keyed AGC pin 23, C23 must be chosen so that AGC
during keyed AGC operation does not become unstable.
Fig. 15
(2) The SD time constant due to the pin 33 muting voltage time constant
The changes in volume due to field fluctuation during weak field reception can be made smoother by setting the
attack and release times during soft muting operation.
Fig. 16
24
S-meter
I24
SD comparator
C24
R24
Mute
amp
Mute
drive
10k
Ω
50k
Ω
C33
33
Attack
Release
Muting time constants
Attack : 10k
Ω × C33
Release : 50k
Ω × C33
SD Sensitivity Adjustment
0
10
20
30
40
50
630
26
22
18
14
10
34
Resistance between the pin and ground -- k
Ω
Antenna
input
such
that
pin
5
goes
high
-
dB
μ
Fig. 17
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| LA1784M | AM/FM, AUDIO SINGLE CHIP RECEIVER, PQFP64 |
| LA1787NM | AM/FM, AUDIO SINGLE CHIP RECEIVER, PQFP64 |
| LA1787NM | AM/FM, AUDIO SINGLE CHIP RECEIVER, PQFP64 |
| LA1800 | AM/FM, AUDIO SINGLE CHIP RECEIVER, PDIP22 |
| LA1805 | AM/FM, AUDIO SINGLE CHIP RECEIVER, PDIP24 |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| LA1781M_09 | 制造商:SANYO 制造商全稱:Sanyo Semicon Device 功能描述:For Car Radios Single-Chip Tuner IC |
| LA1781MA-MPB-E | 功能描述:調(diào)諧器 RoHS:否 制造商:NXP Semiconductors 功能: 噪聲系數(shù): 工作電源電壓: 最小工作溫度: 最大工作溫度: |
| LA1781MD-A-MPB-E | 制造商:ON Semiconductor 功能描述:ANALOG CAR RADIO TUNER - Trays |
| LA1781MD-B-MPB-E | 功能描述:調(diào)諧器 RoHS:否 制造商:NXP Semiconductors 功能: 噪聲系數(shù): 工作電源電壓: 最小工作溫度: 最大工作溫度: |
| LA1781ML-MPB-E | 功能描述:調(diào)諧器 RoHS:否 制造商:NXP Semiconductors 功能: 噪聲系數(shù): 工作電源電壓: 最小工作溫度: 最大工作溫度: |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。