REF200AU

Due to market price fluctuations,if you need to purchase or consult the price.You can contact us or emial to us:   sales@allicdata.com

1. Description

The REF200AU combines three circuit building-blocks on a single monolithic chip: two 100-µA current sources and a current mirror. The sections are dielectrically isolated, making them completely independent. Also, because the current sources are two-terminal devices, they can be used equally well as current sinks. The performance of each section is individually measured and laser-trimmed to achieve high accuracy at low cost. The sections can be pin-strapped for currents of 50 µA, 100 µA, 200 µA, 300 µA, or 400 µA. External circuitry can obtain virtually any current. These and many other circuit techniques are shown in the Application Information section of this data sheet. The REF200 is available in an SOIC package.

2. Features

    1. Completely floating: no power supply or ground connections

    2. High accuracy: 100 µA ±0.5%

    3. Low temperature coefficient: ±25 ppm/°C

    4. Wide voltage compliance: 2.5 V to 40 V

    5. Includes current mirror

3. Applications

    1. Sensor excitation

    2. Biasing circuitry

    3. Offsetting current loops

    4. Low voltage references

    5. Charge-pump circuitry

    6. Hybrid microcircuits

4. Pin configuration

5. Pin Description

6. Feature Description

Drift performance is specified by the box method, as illustrated in Figure 1. The upper and lower current extremes measured over temperature define the top and bottom of the box. The sides are determined by the specified temperature range of the device. The drift of the unit is the slope of the diagonal, typically 25 ppm/°C from –25°C to +85°C.

7. Device functional mode

The three circuit sections of the REF200 are electrically isolated from each other using dielectric isolation manufacturing process. Substrate connections are provided, isolated from all circuits. This pin should Connect to a defined circuit potential to ensure rated DC performance. Preferred connection is The most negative potentiostat in the system. In most analog systems this will be –VS. For best AC performance, leave pin 6 open and leave unconnected parts unconnected.

8. Application Information

The applications for the REF200 are limitless. Application Bulletin AB-165 (SBOA046) shows additional REF200 circuits and other related current source techniques. In this section, a set of circuits are shown to illustrate some techniques. If the current source is subject to reverse voltage, protection diodes may be required. If the reverse voltage is limited to less than 6 V or the reverse current limited to less than 350 µA, protection circuitry is not required. The shunt diode protects the device by limiting the reverse voltage across the current source to approximately 0.7 V. in some In applications, a series diode may be preferable as it does not allow reverse current flow. This However, the configuration reduces the compliance voltage range by one diode drop.