- 您现在的位置：买卖IC网 > PDF目录17298 > TMPSNSRD-TCPL1 (Microchip Technology)BOARD RTD REFERENCE DESIGN PDF资料下载
参数资料
| 型号： | TMPSNSRD-TCPL1 |
| 厂商： | Microchip Technology |
| 文件页数： | 13/30页 |
| 文件大小： | 0K |
| 描述： | BOARD RTD REFERENCE DESIGN |
| 产品培训模块： | MCP3901 Analog Front End |
| 标准包装： | 1 |
| 传感器类型： | 温度，热电偶 |
| 嵌入式： | 否 |
| 已供物品： | 板 |
| 已用 IC / 零件： | MCP3421，MCP9804 |
| 产品目录页面： | 672 (CN2011-ZH PDF) |
第1页第2页第3页第4页第5页第6页第7页第8页第9页第10页第11页第12页当前第13页第14页第15页第16页第17页第18页第19页第20页第21页第22页第23页第24页第25页第26页第27页第28页第29页第30页
Programmable Gain Using Digital Potentiometers
V OUT = – R BW x V IN
Programmable Ampli?er Gain Using a
Digital Potentiometer
Many sensors require their signal to be ampli?ed before
being converted to a digital representation. This signal gain
may be done with and operational ampli?er. Since all sensors
will have some variation in their operational characteristics,
it may be desireable to calibrate the gain of the operational
ampli?er to ensure an optimal output voltage range.
The ?gure below shows two inverting ampli?er with
programmable gain circuits. The generic circuit (a) where R 1 ,
R 2 , and Pot 1 can be used to tune the gain of the inverting
ampli?er, and the simpli?ed circuit (b) which removes
resistors R 1 and R 2 and just uses the digital potentiometers
R AW and R BW ratio to control the gain.
The simpli?ed circuit reduces the cost and board area but
there are trade-offs (for the same resistance and resolution),
Equation 1-1 shows how to calcultate the gain for the
simpli?ed circuit (Figure 1-1b). The gain is the ratio of the
digital potentiometers wiper position on the R AB resistor
ladder. As the wiper moves away from the midscale value,
the gain will either become greater then one (as wiper moves
towards Terminal A), or less then one (as wiper moves
towards Terminal B).
The device’s wiper resistance (R W ) is ignored for ?rst order
calculations. This is due to it being in series with the op amp
input resistance and the op amp input impedence is very
large.
Circuit Gain Equation
R AW
Using the R 1 and R 2 resistors allows the range of the gain
to be limited and therefore each digital potentiometer step
is a ?ne adjust within that range. While in the simpli?ed
R BW =
R AB
# of Resistors
x Wiper Code
circuit, the range is not limited and therefore each digital
potentiometer step causes a larger variation in the gain.
The feedback capacitor (C F ) is used for circuit stability.
Inverting Amplifier with Programmable Gain Circuits
Generic Circuit (a)
Pot 1
R AW = # of Resistors – Wiper Code x R AB
# of Resistors
V IN
R 1
A
B
R 2
W
C F
Op Amp (1)
V OUT
Simplified Circuit (b)
Pot 1
V IN
A
W
B
C F
Op Amp (1)
V OUT
Note 1: A general purpose op amp, such as the MCP6001.
Signal Chain Design Guide
13
相关PDF资料 |
PDF描述 |
|---|---|
| TMPSNSRD-RTD2 | BOARD RTD REFERENCE DESIGN |
| IR2183PBF | IC DRIVER HALF BRIDGE 8DIP |
| IR21814SPBF | IC DRIVER HIGH/LOW SIDE 14SOIC |
| IR1167BSTRPBF | IC SMART SECONDARY DRIVER 8-SOIC |
| IR21814PBF | IC DRIVER HIGH/LOW SIDE 14DIP |
相关代理商/技术参数 |
参数描述 |
|---|---|
| TMPSNS-RTD1 | 功能描述:开发板和工具包 - PIC / DSPIC RTD Temp Sensor Demo Brd RoHS:否 制造商:Microchip Technology 产品:Starter Kits 工具用于评估:chipKIT 核心:Uno32 接口类型: 工作电源电压: |
| TMPT2369ALT | 制造商:ALL 功能描述:ALLEGRO NXC7D |
| TMPT2SU1 | 制造商:Red Lion Controls 功能描述:THERMOCOUPLE TEMP PROBE, TYPE T, 400?F 制造商:Red Lion Controls 功能描述:TYPE T 400DEG F |
| TMPT3906LT | 制造商:ALL 功能描述:ALLEGRO S9K3A |
| TMPT5089LT | 制造商:Allegro MicroSystems LLC 功能描述:Bipolar Junction Transistor, NPN Type, TO-236 |
发布紧急采购，3分钟左右您将得到回复。