U2270B ATMEL Corporation, U2270B Datasheet
U2270B
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U2270B Summary of contents
Page 1
... Access Control • Process Control 1. Description ® The U2270B for IDIC read/write base stations in contactless identification and immobilizer systems. The IC incorporates the energy-transfer circuit to supply the transponder. It consists of an on-chip power supply, an oscillator, and a coil driver optimized for automotive-spe- cific distances. It also includes all signal-processing circuits which are necessary to transform the small input signal into a microcontroller-compatible signal ...
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... Transponder typ. 125 kHz IC Figure 1-2. Block Diagram EXT COIL1 COIL2 Driver DGND Input Lowpass filter U2270B 2 Read/write base station Osc RF field U2270B NF read channel V Power supply = 1 & Amplifier Schmitt trigger HIPASS GND OE Carrier enable MCU Data output V S Batt Frequency ...
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... Function Ground Data output Data output enable Data input Mode select coil 1: common mode/differential mode Carrier frequency enable Driver ground Coil driver 2 Coil driver 1 External power supply Driver supply voltage Battery voltage Standby input Internal power supply (5V) Frequency adjustment DC decoupling U2270B 3 ...
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... Power Supply (PS) Figure 3-1. COILx The U2270B can be operated with one external supply voltage or with two externally-stabilized supply voltages for an extended driver output voltage or from the 12V battery voltage of a vehi- cle. The 12V supply capability is achieved via the on-chip power supply (see ...
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... Operation Modes to Power the U2270B The following section explains the three different operation modes to power the U2270B. 3.2.1 One-rail Operation All internal circuits are operated from one 5V power rail (see and D VS Figure 3-2. 3.2.2 Two-rail Operation In this application, the driver voltage, D higher voltage than the rest of the circuitry to obtain a higher driver-output swing and thus a higher magnetic field (see ages can be as high as 8V ...
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... For 125 kHz, a resistor value of 110 k is defined. For other frequencies, use the following formula This input can be used to adjust the frequency close to the resonance of the antenna. For more details see Section Figure 3-5. U2270B 6 Battery Operation EXT Supply-voltage Range ...
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... Equivalent Circuit of Pin Input R Input can be assumed for selected data rates can be found in HP 10. / 18, and data rates up to Osc . For frequency response calculation, the 0.4V Bias 10 k 210 0.4V Bias Section U2270B Fig- Section 4., 4., “Applications” ...
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... Schmitt Trigger The signal is processed by a Schmitt trigger to suppress possible noise and to make the signal microcontroller-compatible. The hysteresis level is 100 mV symmetrically to the DC operation point. The open-collector output is enabled by a low level at OE (pin 3). Figure 3-8. U2270B 8 Equivalent Circuit of Pin HIPASS R R LPF ...
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... This is achieved by interrupting the RF field with short gaps. The various functions are controlled by the inputs MS and CFE (see is shown in Figure 3-9. Figure 3-10. Equivalent Circuit of Pin CFE 4684E–RFID–02/08 “Function Table” on page Figure 3-1 on page 4. Equivalent Circuit of Pin MS MS CFE 10). The equivalent circuit of the driver 30 µA 30 µA U2270B 9 ...
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... U2270B can be used. In this case, standby mode can be used and an exter- nal low-current microcontroller can be supplied supply rail is available, it can be used to power the U2270B. In this case, check that the voltage is noise-free. An external power transistor is not necessary. The application also depends on the magnetic-coupling situation. The coupling factor mainly depends on the transmission distance and the antenna coils ...
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... The application of the U2270B includes the two capacitors C early dependent on the transponder’s data rate. The following table gives the appropriate values for the most common data rates. The values are valid for Manchester and bi-phase code. Table 4-2. Data Rate f = 125 kHz ...
Page 12
... Basic application using diode feedback. This application allows higher communication distances than .“Application 1” Figure 4- 100 k 1.2 nF 1.35 mH Antenna 1N4148 470 k U2270B 12 Application Circuit 1N4148 + 4 µ EXT RF COIL2 U2270B 82 COIL1 Input C IN HIPASS C 1 DGND BC639 360 + 22 µ µ Batt DD MS CFE Micro- Standby ...
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... Application 3 This application is comparable to higher antenna resonance tolerances and/or higher communication distances. This application is preferred if the detecting microcontroller is close to the U2270B additional microcontrol- ler signal controls the adequate operating frequency. Figure 4- 100 1.5 mH Antenna 1N4148 180 pF 100 BC846 Note: 4684E– ...
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... Junction temperature Storage temperature Ambient temperature 6. Thermal Resistance Parameter Thermal resistance SO16 7. Operating Range All voltages are referred to GND (Pins 1 and 7) Parameter Operating voltage Operating voltage Operating voltage 10, 11 Carrier frequency U2270B 14 Pin Symbol 12 V Batt Coil S, EXT Coil 2 ...
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... V 2.4 0 3 4.6 5.4 6 /dT 4 1.8 3 2.9 3.6 4.3 DRV V 3.1 4.0 4.7 DRV V 4.6 5.4 6.3 EXT dV /dT 4.2 EXT I 3.5 EXT I 0.4 EXT 121 125 129 cut 30 U2270B Unit µ kHz kHz 15 ...
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... Ordering Information Extended Type Number U2270B-MFPY U2270B-MFPG3Y 10. Package Information Package Dimensions in mm 0.4 1. U2270B 16 Package Remarks SO16 Tube, Pb-free SO16 Taped and reeled, Pb-free 9.9 ±0.1 8. Pin 1 identity 5 ±0.2 3.7 ±0.1 3.8 ±0.1 6 ±0.2 technical drawings according to DIN specifications Drawing-No.: 6.541-5031.02-4 Issue: 1; 15.08.06 ...
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... Section 10 “Package Information” on page 16 changed Minor grammatical corrections and fixed broken cross references Last page: Legal sentence changed Put datasheet in a new template Pb-free Logo on page 1 added New heading rows on Table “Absolute Maximum Ratings” on page 14 added Ordering Information on page 16 changed U2270B alignment S 17 ...
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... Atmel products are not suitable for, and shall not be used in, automotive applications. Atmel’s products are not intended, authorized, or warranted for use as components in applications intended to support or sustain life. © 2008 Atmel Corporation. All rights reserved. Atmel marks of Atmel Corporation or its subsidiaries. Other terms and product names may be trademarks of others. International Atmel Asia ...