SI1102-A-GM Silicon Laboratories Inc, SI1102-A-GM Datasheet

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... The Si1102 consists of a patented, high-EMI immunity, differential photodiode and a signal-processing IC with LED driver and high-gain optical receiver. Proximity detection is based on measurements of reflected light from a strobed, optically-isolated LED. The standard package for the Si1102 pin ODFN. Functional Block Diagram Infrared ...

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Si 1102 2 Rev. 1.0 ...

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... Application Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7 3.1. Theory of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7 3.2. Choice of LED and LED Current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8 3.3. Power-Supply Transients . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8 3.4. Mechanical and Optical Implementation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8 3.5. Typical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 4. Pin Descriptions—Si1102 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 5. Ordering Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 6. Photodiode Center . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 7. Package Outline (8-Pin ODFN .14 Document Change List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15 Contact Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16 Rev ...

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Si 1102 1. Electrical Specifications Table 1. Absolute Maximum Ratings Parameter Supply Voltage Operating Temperature Storage Temperature Voltage on TXO with respect to GND Voltage on all other Pins with respect to GND Maximum total current through TXO (TXO Active) ...

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... V, LED I = 400 3  3 100 k  3 (open 3.3 V, 850 nm source 3 3 strobe 3 TXO 80% TXO = TXO1V Rev. 1.0 Si1102 Min Typ Max Units VDD – 0.6 — — V — — 0.6 V — 0.1 1.0 µA 30 120 200 µA — µA — 8 — ...

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... Note: R1 resistance should be factory-adjustable to achieve a consistent proximity object detection threshold across different combinations of irLED, product window, and sensor sensitivity. Figure 1. Application Example of the Proximity Sensor Using a Single Supply 6 1 PRX PRX 2 TXGD 3 TXO TxLED 4 DNC Si1102 Rev. 1.0 8 VSS SREN VDD 100 k 100 k ...

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... An LED sends light pulses whose reflections reach a photodiode and are processed by the Si1102’s analog circuitry. If the reflected light is above the detection threshold, the Si1102 asserts the active-low PRX output to indicate proximity. This output can be used as a control signal to activate other devices interrupt signal for microcontrollers ...

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... If an existing enclosure is being reused and does not have dedicated openings for the LED and the Si1102, the proximity detector may still work if the optical loss factor through improvised windows (e.g. nearby microphone or fan holes) or semi-opaque material is not more than 90% in each direction. In addition, the internal reflection from an encased device's PMMA (acrylic glass) window (common in cellular telephones, PDAs, etc ...

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... At any given R1 threshold setting, there are many factors that determine the precise distance that the Si1102 reports. These factors include object reflectivity, object size, ambient light type and ambient light intensity. When used in applications where the ambient light is variable recommended the Si1102 optical window be IR transmissive but visible light opaque. ...

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Si 1102 3.5. Typical Characteristics Cycle Period vs R1 1000 100 (Kohm) Figure 4. Cycle Period vs. R2 (R1 = 5.1 k, Vtxo = 1 V) Idd Idle 180 5.0 volts 3.3 volts ...

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... Figure 10. Proximity Detection Distance vs. Ambient Light (with IR Filter) 18% Gray Card, CFL 300 lx 82% White Card CFL 300 lx 18% Gray Card, Incandescent 300 lx 82% White Card, Incandescent 300 100 18% Gray Card 18% Gray Card, CFL 300 lx 18% Gray Card, CFL 1000 100 Rev. 1.0 Si1102 11 ...

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... Si 1102 4. Pin Descriptions—Si1102 Pin Name Type 1 PRX Output 2 TXGD Ground 3 TXO Output VDD Input 6 SREN Input 7 FR Input 8 VSS Ground 12 PRX 1 8 VSS TXGD TXO 3 6 SREN VDD Figure 11. Pin Configuration Table 5. Pin Descriptions Description Proximity Output . Normally high; goes low when proximity is detected. When device is not enabled, the PRX pulls- ...

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... Ordering Guide Part Ordering # Si1102-A-GM 6. Photodiode Center Temperature –40 to +85 °C 0.8 Figure 12. Photodiode Center Rev. 1.0 Si1102 Package 3x3 mm ODFN8 1.5 13 ...

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... Si 1102 7. Package Outline (8-Pin ODFN) Figure 13 illustrates the package details for the Si1102 ODFN package. Table 6 lists the values for the dimensions shown in the illustration. Figure 13. ODFN Package Diagram Dimensions Table 6. Package Diagram Dimensions Dimension aaa bbb ccc ddd Notes: 1. All dimensions shown are in millimeters (mm). ...

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... Revision 0.7 to Revision 0.8  Updated Tables and 5.  Updated Figures 11, and 12. Revision 0.8 to Revision 1.0  Updated Table 2, Table 3, and Table 5  Updated Figure 1 and Figure 6.  Updated Section 3.4 concerning usage of small R1 values.  Added "6. Photodiode Center" on page 13. Rev. 1.0 Si1102 15 ...

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