参数资料
型号: THS4223D
厂商: TEXAS INSTRUMENTS INC
元件分类: 音频/视频放大
英文描述: 3 CHANNEL, VIDEO PREAMPLIFIER, PDSO14
封装: PLASTIC, SOIC-14
文件页数: 8/32页
文件大小: 411K
代理商: THS4223D
THS4221, THS4225
THS4222, THS4226
THS4223, THS4227
SLOS399C – AUGUST 2002 – REVISED JANUARY 2003
www.ti.com
16
The time delays associated with turning the device on and
off are specified as the time it takes for the amplifier to
reach 50% of the nominal quiescent current. The time
delays are on the order of microseconds because the
amplifier moves in and out of the linear mode of operation
in these transitions.
Power-Down Reference Pin Operation
In addition to the power-down pin, the THS4225 and
THS4227 features a reference pin (REF) which allows the
user to control the enable or disable power-down voltage
levels applied to the PD pin. Operation of the reference pin
as it relates to the power-down pin is described below.
In most split-supply applications, the reference pin is
connected to ground. In some cases, the user may want
to connect it to the negative or positive supply rail. In either
case, the user needs to be aware of the voltage level
thresholds that apply to the power-down pin. The tables
below show examples and illustrate the relationship
between the reference voltage and the power-down
thresholds.
POWER-DOWN THRESHOLD VOLTAGE LEVELS (REF
≤ Midrail)
SUPPLY
VOLTAGE
REFERENCE PIN
ENABLE
DISABLE
VOLTAGE
(V)
REFERENCE PIN
VOLTAGE (V)
ENABLE
LEVEL (V)
DISABLE
LEVEL (V)
GND
≥ 1.8
≤ 1
±5
–2.5
≥ –0.7
≤ –1.5
±5
–5
≥ –3.2
≤ –4
GND
≥ 1.8
≤ 1
5
1
≥ 2.8
≤ 2
5
2.5
≥ 4.3
≤ 3.5
3.3
GND
≥ 1.8
≤ 1
In the above table, the threshold levels are derived by the
following equations:
REF + 1.8 V for enable
REF + 1 V for disable
Note that in order to maintain these threshold levels, the
reference pin can be any voltage between Vs– or GND up
to Vs/2 (mid rail).
For 3.3-V operation, the reference pin must be connected
to the most negative rail (for single supply this is GND).
POWER-DOWN THRESHOLD VOLTAGE LEVELS (REF > Midrail)
SUPPLY
VOLTAGE
REFERENCE PIN
ENABLE
DISABLE
VOLTAGE
(V)
REFERENCE PIN
VOLTAGE (V)
ENABLE
LEVEL (V)
DISABLE
LEVEL (V)
Floating or 5
≥ 4
≤ 3.5
±5
2.5
≥ 1.5
≤ 1
±5
1
≥ 0
≤ –0.5
Floating or 5
≥ 4
≤ 3.5
5
4
≥ 3
≤ 2.5
5
3.5
≥ 2.5
≤ 2
3.3
Floating or 3.3
≥ 2.7
≤ 1.8
In the above table, the threshold levels are derived by the
following equations:
REF – 1 V for enable
REF – 1.5 V for disable
Note that in order to maintain these threshold levels, the
reference pin can be any voltage between (Vs+/2) + 1 V to
Vs+ or left floating. The reference pin is internally
connected to the positive rail, therefore it can be left
floating to maintain these threshold levels.
For 3.3-V operation, the reference pin must be connected
to the positive rail or left floating.
The recommended mode of operation is to tie the
reference pin to midrail, thus setting the threshold levels to
mid-rail +1.0 V and midrail +1.8 V.
NO. OF CHANNELS
PACKAGES
Single (8-pin)
THS4225D,THS4225DGN
Triple (16-pin)
THS4227PWP
Power Supply Decoupling Techniques and
Recommendations
Power supply decoupling is a critical aspect of any
high-performance amplifier design process. Careful
decoupling provides higher quality ac performance (most
notably improved distortion performance). The following
guidelines ensure the highest level of performance.
1.
Place decoupling capacitors as close to the power
supply inputs as possible, with the goal of minimizing
the inductance of the path from ground to the power
supply.
2.
Placement priority should put the smallest valued
capacitors closest to the device.
3.
Use
of
solid
power
and
ground
planes
is
recommended to reduce the inductance along power
supply return current paths, with the exception of the
areas underneath the input and output pins.
4.
Recommended values for power supply decoupling
include a bulk decoupling capacitor (6.8 to 22
F), a
mid-range decoupling capacitor (0.1
F) and a high
frequency decoupling capacitor (1000 pF) for each
supply. A 100 pF capacitor can be used across the
supplies as well for extremely high frequency return
currents, but often is not required.
相关PDF资料
PDF描述
THS4227PWPR 3 CHANNEL, VIDEO PREAMPLIFIER, PDSO16
THS4227PWP 3 CHANNEL, VIDEO PREAMPLIFIER, PDSO16
THS4227DR 3 CHANNEL, VIDEO PREAMPLIFIER, PDSO16
THS4227D 3 CHANNEL, VIDEO PREAMPLIFIER, PDSO16
THS4225DGNRG4 1 CHANNEL, VIDEO PREAMPLIFIER, PDSO8
相关代理商/技术参数
参数描述
THS4223PWP 制造商:Rochester Electronics LLC 功能描述:- Bulk
THS4225 制造商:TI 制造商全称:Texas Instruments 功能描述:LOW-DISTORTION, HIGH-SPEED, RAIL-TO-RAIL OUTPUT OPERATIONAL AMPLIFIERS
THS4225D 功能描述:高速运算放大器 Low-Distortion High Speed R-to-R Output RoHS:否 制造商:Texas Instruments 通道数量:1 电压增益 dB:116 dB 输入补偿电压:0.5 mV 转换速度:55 V/us 工作电源电压:36 V 电源电流:7.5 mA 最大工作温度:+ 85 C 安装风格:SMD/SMT 封装 / 箱体:SOIC-8 封装:Tube
THS4225D 制造商:Texas Instruments 功能描述:IC OP-AMP VFB R-R 120MHZ LV 8SOIC 制造商:Texas Instruments 功能描述:IC, OP-AMP VFB R-R 120MHZ LV 8SOIC 制造商:Texas Instruments 功能描述:IC, OP-AMP VFB R-R 120MHZ LV 8SOIC; Op Amp Type:Low Distortion; No. of Amplifiers:1; Slew Rate:975V/s; Supply Voltage Range: 1.35V to 7.5V; Amplifier Case Style:SOIC; No. of Pins:8; Bandwidth:230MHz; Operating Temperature ;RoHS Compliant: Yes
THS4225DG4 功能描述:高速运算放大器 Low-Distortion High Speed R-to-R Output RoHS:否 制造商:Texas Instruments 通道数量:1 电压增益 dB:116 dB 输入补偿电压:0.5 mV 转换速度:55 V/us 工作电源电压:36 V 电源电流:7.5 mA 最大工作温度:+ 85 C 安装风格:SMD/SMT 封装 / 箱体:SOIC-8 封装:Tube