參數資料
型號: LT1204
廠商: Linear Technology Corporation
英文描述: 4-Input Video Multiplexer with 75MHz Current Feedback Amplifier
中文描述: 4輸入視頻多路復用器與75MHz的電流反饋放大器
文件頁數: 15/20頁
文件大?。?/td> 330K
代理商: LT1204
15
LT1204
U
S
A
Multiplexer Expansion Pin 11 and Pin 12
O
PPLICATI
W
U
I FOR ATIO
U
To expand the number of MUX inputs, LT1204s can be
paralleled by shorting their outputs together. The multi-
plexer disable logic has been designed to prevent shoot-
through current when two or more amplifiers have their
outputs shorted together. (Shoot-through current is a
spike of power supply current caused by both amplifiers
being on at once.)
Monitoring Supply Current Spikes
The multiplexer uses a circuit to ensure the disabled
amplifiers do not load or alter the cable termination. When
the LT1204 is disabled (Pin 11 low) the output stage is
turned off and an active buffer senses the output and
drives the feedback pin to the CFA (Figure 2). This boot-
straps the feedback resistors and raises the true output
impedance of the circuit. For the condition where R
F
= R
G
= 1k, the Disable Output Resistance is typically raised to
25k and drops to 20k for A
V
= 10, R
F
= 2k and R
G
= 222
due to loading of the feedback buffer. Operating the
Disable feature with R
G
< 100
is not recommended.
A shutdown feature (Pin 12 low) reduces the supply
current to 1.5mA and lowers the power dissipation
when the LT1204 is not in use. If the part is shut down,
the bootstrapping is inoperative and the feedback resis-
tors will load the output. If the CFA is operated at a gain
of +1, however, the feedback resistor will not load the
output even in shutdown because there is no resistive
path to ground, but there will be a –6dB loss through
the cable system.
A frequency response plot shows the effect of using the
disable feature versus using the shutdown feature. In
this example four LT1204s were connected together at
their outputs forming a 16-to-1 MUX. The plot shows the
effect of the bootstrapping circuit that eliminates the
+
+
+
+
LT1204
EN
1
3
5
7
13
14
11
V
16
V
+
TO SCOPE
15
75
+
+
+
+
LT1204
1
3
5
7
13
14
11
EN
V
16
15
1k
1k
75
V
+
74HC04
75
TEK
CT-1
O
5V
OSCILLATOR
1204 AI13
1k
1k
Timing and Supply Current Waveforms
OSCILLATOR
5V/DIV
V
1V/DIV
I
S
10mA/DIV
74HC04
OUTPUT
5V/DIV
1204 AI14
TEE SWITCH
V
IN0
TEE SWITCH
V
IN1
TEE SWITCH
V
IN2
TEE SWITCH
V
IN3
V
LT1204
“ON”
+
CFA
“OFF”
FB
R
F
R
G
V
OUT
75
75
CABLE
1204 F02
A
V
= +1
75
Figure 2. Active Buffer Drives FB Pin 13
相關PDF資料
PDF描述
LT1204CN 4-Input Video Multiplexer with 75MHz Current Feedback Amplifier
LT1204CSW 4-Input Video Multiplexer with 75MHz Current Feedback Amplifier
LT1207 Dual 250mA/60MHz Current Feedback Amplifier
LT1207CS Dual 250mA/60MHz Current Feedback Amplifier
LT1210 1.1A, 35MHz Current Feedback Amplifier
相關代理商/技術參數
參數描述
LT1204CN 功能描述:IC VIDEO MUX CFA 75MHZ 4IN 16DIP RoHS:否 類別:集成電路 (IC) >> 線性 - 放大器 - 視頻放大器和頻緩沖器 系列:- 標準包裝:1,000 系列:- 應用:驅動器 輸出類型:差分 電路數:3 -3db帶寬:350MHz 轉換速率:1000 V/µs 電流 - 電源:14.5mA 電流 - 輸出 / 通道:60mA 電壓 - 電源,單路/雙路(±):5 V ~ 12 V,±2.5 V ~ 6 V 安裝類型:表面貼裝 封裝/外殼:20-VFQFN 裸露焊盤 供應商設備封裝:20-QFN 裸露焊盤(4x4) 包裝:帶卷 (TR)
LT1204CN#PBF 功能描述:IC VIDEO MUX CFA 75MHZ 4IN 16DIP RoHS:是 類別:集成電路 (IC) >> 線性 - 放大器 - 視頻放大器和頻緩沖器 系列:- 標準包裝:1,000 系列:- 應用:驅動器 輸出類型:差分 電路數:3 -3db帶寬:350MHz 轉換速率:1000 V/µs 電流 - 電源:14.5mA 電流 - 輸出 / 通道:60mA 電壓 - 電源,單路/雙路(±):5 V ~ 12 V,±2.5 V ~ 6 V 安裝類型:表面貼裝 封裝/外殼:20-VFQFN 裸露焊盤 供應商設備封裝:20-QFN 裸露焊盤(4x4) 包裝:帶卷 (TR)
LT1204CS 制造商:未知廠家 制造商全稱:未知廠家 功能描述:4-Channel Analog Multiplexer
LT1204CSW 功能描述:IC VIDEOMUX CFA 75MHZ 4IN 16SOIC RoHS:否 類別:集成電路 (IC) >> 線性 - 放大器 - 視頻放大器和頻緩沖器 系列:- 標準包裝:1,000 系列:- 應用:驅動器 輸出類型:差分 電路數:3 -3db帶寬:350MHz 轉換速率:1000 V/µs 電流 - 電源:14.5mA 電流 - 輸出 / 通道:60mA 電壓 - 電源,單路/雙路(±):5 V ~ 12 V,±2.5 V ~ 6 V 安裝類型:表面貼裝 封裝/外殼:20-VFQFN 裸露焊盤 供應商設備封裝:20-QFN 裸露焊盤(4x4) 包裝:帶卷 (TR)
LT1204CSW#PBF 功能描述:IC VIDEOMUX CFA 75MHZ 4IN 16SOIC RoHS:是 類別:集成電路 (IC) >> 線性 - 放大器 - 視頻放大器和頻緩沖器 系列:- 產品培訓模塊:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 標準包裝:50 系列:- 應用:TFT-LCD 面板:VCOM 驅動器 輸出類型:滿擺幅 電路數:1 -3db帶寬:35MHz 轉換速率:40 V/µs 電流 - 電源:3.7mA 電流 - 輸出 / 通道:1.3A 電壓 - 電源,單路/雙路(±):9 V ~ 20 V,±4.5 V ~ 10 V 安裝類型:表面貼裝 封裝/外殼:8-TSSOP,8-MSOP(0.118",3.00mm 寬)裸露焊盤 供應商設備封裝:8-uMax-EP 包裝:管件