Features

Power range:+2.7V to+36V, ± 1.35V to ± 18V

Low noise: 19V/√Hz

RFI filter input

The input range includes negative power

; Rail -to -track output

gain bandwidth: 1.2MHz

Low static current: each amplifier 110 μA

High Communist Party Model suppression: 120db

Low bias current: 15Pa (maximum)

–8 stitch MSOP

–14 needle TSSOP

Micro packaging:

- Single core 5 -needle SOT553

- Double Enter 8 stitches vsop

Application

Track amplifier in the power module

commercial power supply

sensor Amplifier

bridge amplifier

Temperature measurement

Pointer

Battery power supply instrument

Test equipment

Explanation

OPA170, OPA2170 and OPA4170 (OPAX170) are one The series of 36V single power supply low noise computing amplifiers is characterized by working under the power supply of+2.7V (± 1.35V) to+36V (± 18V). They provide good offset, drift and bandwidth and low static current. Single, double and four versions have the same specifications to achieve the maximum design flexibility.

Unlike most of the operational amplifier specified at a power supply voltage, the voltage range of the OPAX170 series operational amplifier is+2.7V to+36V. The input signal beyond the power guide rail does not cause phase reversal. The capacitance load of OPAX170 series is as high as 300pf, and the performance is stable. The input can work under a 100mV voltage under a negative, and work normally within the rail 2V range. Please note that these devices can be positiveThe entire rail of 100 millivol to run in the rail input, but the performance is reduced within the rail 2V range.

OPA170 has SOT553, SOT23-5 and SO-8 packages. Dual OPA2170 has VSSOP-8, MSOP-8 and SO-8 software packages. Quad OPA4170 is packed with TSSOP-14 and SO-14. The prescribed temperature of the OPAX170 computing amplifier is -40 ° C to+125 ° C.

The minimum packaging of 36V computing amplifier

Typical features

vs u003d ± 18v, vcm u003d vs/2, road, road u003d 10kΩ, connect to VS/2, CL u003d 100pf, unless there is another instructions.

Application information OPAX170 series operational amplifier provides high overall performance. These devices are ideal choices for many general applications. The good offset drift of only 2 μV/° C provides excellent stability throughout the temperature. In addition, the device has the overall performance of CMRR, PSRR and AOL. Like all amplifiers, the application of noise or high -impedance power supply requires the decoupling capacitor near the device pin. In most cases, 0.1 μF capacitors are enough. Working features The operating voltage of the OPAX170 series amplifier is 2.7V to 36V (± 1.35V to ± 18V). Many specifications are suitable for -40 ° C to+125 ° C. The typical features are given significant parameters related to work voltage or temperature. Total plane layout guide In order to obtain the best equipment operation performance, it is recommended to use a good printing circuit board (PCB) layout method. Low loss 0.1 μF bypass power container should be connected between the pilot and ground of each power, and as close to the device as much as possible. Single -width capacitors from V+to the ground are suitable for single power applications.

Common mode voltage range

The input co -mode voltage range of the OPAX170 series extends to 100mV below the negative, and it is within the 2V range of the positive polar rail 2V during normal operation.

This device can be run under the entire rails of 100 millivoltors outside the orbit, but the performance is reduced within the rail 2V range. Table 2 summarizes the typical performance within this range.

Phase protection

OPAX170 series has internal phase reversal protection. When the input is driven by its linear co -modular range, many operationsBullets will have phase reversal. This situation is the most common in non -switching circuits. When the input is driven to the co -mode voltage range that exceeds the specified specified, the output reverse into the opposite track. The input of OPAX170 prevents the phase reversal voltage of too much co -mode. Instead, the output restrictions input the corresponding track. This performance is shown in Figure 37.

The dynamic characteristics of capacity load and stability

OPAX170 have been optimized for common operating conditions. The binding of low -closed cycle gains and high -inclusive loads reduces the phase margin of the amplifier and may lead to peak or oscillation of gain. Therefore, the heavier capacitance load must be isolated from the output. The easiest way to achieve this isolation is to connect a small resistance in series at the output end (for example, ROUT is equal to 50Ω). Figures 38 and Figure 39 show that the relationship between the small signal super -adjustment and the capacitance load is defeated. In addition, the detailed information about analysis technology and application circuits, please refer to the application announcement AB-028, and the feedback diagram defines the operation of the operation amplifier (can be downloaded from the TI website).

Excessive electrical stress

Designers often ask the capabilities of the operation amplifier to withstand excessive electrical stability. These problems are often concentrated on the device input, but may involve the power supply voltage pins and even output pins. Each different pins function has the electrical stability limit determined by the voltage breakdown characteristics of a specific semiconductor manufacturing process and a specific circuit connected to the pin. In addition, internal electrostatic discharge (ESD) is protected in these circuits to prevent an ESD incident that occurs before and in the process of product assembly.

These ESD protection diode also provides input -drive protection in the circuit. As long as the current is limited to 10 mAh, as described as absolutely maximum rated values. FIG. 40 shows how to add a series input resistance to the driver input to limit the input current. In its application, the input noise of the thermistor should be kept at minimal.

The ESD event will generate a short -lasting high -voltage pulse. When it discharge through semiconductor devices, the pulse is converted into a short duration and large current pulse. The ESD protective circuit design is used to provide a current circulation around the core of the computing amplifier to prevent it from being damaged. The energy absorbed by the protective circuit was subsequently lost in the form of heat. When the operational amplifier is connected to the circuit, the ESD protection component will maintain a non -activity state without participating in the application circuit operation. However, when the external voltage exceeds the operating voltage range of the given pin, this may occur. If this happens, there are risks that some internal ESD protection circuits may be biased and transmitted. Any current is generated by electrostatic discharge units, which rarely involves an absorption device.

If the capacity of the power absorption current existsUncertainty can add an external Qina diode to the power pins.The Qina voltage must be selected so that the diode will not be turned on during the normal operation.However, its Qina voltage should be low enough to turn on the Qina diode when the power pins start to rise to the level of the safe working power supply voltage level.