General description

lmv341 / lmv342 /LMV344 is single, double and four low voltage, low power consumption amplifier. They are designed for low -voltage portable applications. Other important product features are low input bias currents, rail output and wide temperature range. The patented AB turnover phase significantly reduces noise, power consumption and departure set voltage at higher frequencies. PMOS input phase provides users with ultra -low input bias current 20FA (typical) and high input impedance. The industrial -grade temperature range from -40 ° C to 125 ° C can reduce LMV341/LMV342/LMV344 to adapt to a wide range of environmental applications. LMV341 EX PANDS National Semiconductor's silicon dust #8482; amplifier side Folio provides enhancement of dimensions, speed, and power. LMV341/LMV342/LMV344 guarantees the working rail to pass from the voltage range from 2.7V to 5.5V. LMV341 provides a closure of pins that can be used to disable devices. Once in the shutdown mode, the power current will be reduced to 45Pa (typical value). LMV341/LMV342/LMV344 has a 29nv voltage noise rate at 29nv voltage noise rates at the time of 10kHz, 1MHz GBW, 1.0V/μS conversion, 0.25mvOS and 0.1 μA off current (LMV341.) LMV341 packaged LMV342 with a miniature 6 -needle SC70, which saved the 8 -pin MSOP of space. And soIC, and LMV344, 14 -needle TSSOP and SOIC. These small parcel amplifiers provide the ideal solution for the need for the required application to occupy the area. Applications with area constraints PC boards include portable electronic devices such as mobile phones and palm computers.

Features

(Typical 2.7V power supply; unless there are other instructions)

Guarantee 2.7V and 5V specifications

Enter reference voltage noise (@ [ 10kHz) 29nv/√Hz

Power current (each amplifier) 100 μA

gain bandwidth multiplication 1.0MHz

conversion rate 1.0V/μs

Standard Disted current (LMV341) 45Pa

Opening time after shutdown (LMV341) 5 μs

Input bias current 20fa

Application

Wanderer/mobile phone [ 123]

notebook computer

pda

pcmcia/audio

Portable/battery power supply electronic equipment

Power current supervisionTest

Battery monitoring

buffer

Filter

Absolutely maximum rated value (Note 1)

ESD tolerance (Note 2 2 )

Machine model 200V

Human model 2000V

Differential input voltage ± power voltage

Power voltage (V+-V ) 6.0V

Output to V+short-circuit (Note 3)

Output pair V-short circuit (Note 4)

Storage temperature range 65 ° C to 150 ° C

Jienc (Note 5) 150 ° C

Installation temperature

Infrared or counter -flow welding (20 seconds) 235 ° C

Diversion temperature. (10 seconds) 260 ° C

Work rated value (Note 1)

Power voltage 2.7V to 5.5V

Temperature range 40 ° C to 125 ° C

Thermal resistance (θja)

6 -needle SC70 414 ° C/W

8 -needle SOIC 190 ° C/W

8 -needle MSOP 235 ° C/W

14 -needle TSSOP 155 ° C/W

14 -needle SOIC 145 ° C/W

2.7V DC electricity characteristics (Note 10) [123 ]

Unless there are other regulations, all the restrictions of TJ are guaranteed 25 ° C, V+ 2.7 volts, V 0 volts, vcm v+/2, vo v+/2 and rl gt; 1 trillion Euros. Rough body limit is suitable for extreme temperature.

5V DC special (Note 10)

Unless there are other regulations, all the restrictions of TJ are guaranteed 25 ° C, V+ 5V , V 0V, VCM V+/2, VO V+/2 and R GT; 1M . Bold facial restrictions are suitable for extreme temperature.

Note 1: Absolute maximum rated value indicates the limit value that may be damaged by the device. The working conditions of the work are designed to play the function of the equipment, but the specific performance cannot be guaranteed. Please refer to the electrical characteristics about the specifications and test conditions of the guarantee.

Note 2: Human model, applicable standard MIL-STD-883, method 3015.7. Machine model, applicable standard JESD22-A115-A (JEDEC's ESD MM (M standard) Fields for charge device models, applicable standards JESD22-C101-C (Jedec's ESD FICDM standard).

Note 3: The short -circuit to V+will adversely affect the reliability.

Note 4: Output will adversely affect reliability.

Note 5: The maximum power consumption is the function of TJ (MAX) θJa. The maximum allowable power consumption at any ambient temperature (TJ (maximum value) – TA all numbers are suitable for packaging directly welded to the PC board.

Note 6: Typical value is the most likely determined when the representation of the representation is most likely The parameter specifications. The actual typical value may change over time depends on the application and configuration. The typical value is not tested and does not guarantee the production materials of the transportation.

Note 7: All limit values Both are guaranteed by the test or statistical analysis.

Note 8: RL

to the middle power supply. The output voltage is GND+0.2V ≤V+ 0.2V

Note 9: As a voltage follower connection, 2VPP steps are input. The specified number is the slower of the positive and negative conversion rate.

Note 10: The value of the electrical meter is only applicable to the specified temperature. Factory test conditions. Factory testing conditions caused very limited self -heating. Under the internal heating conditions of TJ TA, there is no guarantee of parameter performance in the electrical meter. Among them, TJ GT;

Typical performance features

]

123] Application part

LMV341/LMV342/LMV344LMV341/LMV342/LMV344 series amplifier has low pressure, low power consumption, rail -to -orbit output amplifier, designed for low -pressure portable applications. This series uses this series. All CMOS process design. This leads to ultra -low input bias current. The LMV341 shutdown option can be used to increase the battery life. The Simplified schematic diagram of the LMV341/LMV342/LMV344 series amplifier is shown in Figure 1. Including ground. The output of the difference is connected to the AB class turnover stage. Compared with the conventional weekly turn, the AB -level weekly transfers have a lower static current. The turnover phase. The output AB -level turnover stage is the output complementary common source crystal tube stage. These transistors enable the device to be transmitted on track.

AB class turnover level Amplifier

This patent folding conclusions and gridThere is a combination AB -level amplifier level, which replaces the traditional folding CAS encoding level. Therefore, the static current is much lower than that of the traditional folding co -source grid level compared with the traditional folding co -source grid level. This will lead to smaller offset and noise contribution. The reduction of the offset and noise contribution in turn reduces the offset voltage level and the voltage noise level of the LMV341/LMV342 input terminal/LMV344. At the same time, lower static currents can cause the opening gain of the amplifier. The lower static current does not affect the conversion rate of the amplifier, nor does it affect the amplifier processing to process the total current swing from the input stage. The input voltage noise of this device at low frequency is 1kHz, which is slightly higher than the device entered by BJT. However, the result of the PMOS input stage is that when the frequency is higher than 1kHz, the input bias current and the input voltage noise will be reduced.

Sampling maintenance circuit

LMV341 with low input bias current causes high input impedance. When the device is in the shutdown mode, the output impedance is quite high. These high impedance, as well as the ability to cut off sales from an independent power supply, make LMV341 a good sample and choice of maintaining circuits. The sample clock should be quickly connected to the shutdown pin of the amplifier to open or close the device. Figure 2 shows a simple Sample-And-Hold schematic diagram circuit. When the sampling clock is high, the first amplifier is in normal working mode, and the second amplifier is used as a buffer. The capacitor, at the first amplifier, is charging at this time. The non -inverter input of the first amplifier through the capacitor is connected as a voltage follower. When the sample clock is low, the first amplifier is closed, bringing high output impedance. The high impedance of this output, as well as the high impedance amplifier of the second input end to prevent the capacitor from discharging. When the first amplifier is closed, the voltage drops a small mode. The second amplifier, it is still connected with the normal working mode and as a voltage follower, and also provides a voltage sampled voltage sampled at the capacitor output end.

The shutdown function

LMV341 can be turned off in order to provide power and extend battery life in portable devices. Once in the shutdown mode, the power current will be greatly reduced, the maximum value is 1 μA, and the output will be ""three -state"" as the shutdown pin voltage is pulled down. The shutdown pin must not be disconnected. Keeping the pin float will cause an unabated operation mode, and the device may oscillate and activate mode between shutdown. LMV341 usually turns on 2.8 μs after pulling the per stop voltage. After that, the device will turn off the voltage and lower the voltage within less than 400 NS. Figure 3 and 4 show the opening time and closing time of LMV341. In order to reduce the influence of the capacitor, the oscilloscope probe, there is a load of 600 in the turning time circuit. Figures 5 and 6 show the tests that are used to obtain two curve charts.

Low input bias current

LMV341/LMV342/LMV344 amplifier has a PMO in the output stage.Therefore, their input deviations are much lower than equipment that is greater than the BJT input level.This feature makes these devices the ideal choice for sensor circuits.The input bias current of the typical curve LMV341 is shown in Figure 7.