unicore UM621N, Reference Design

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1
1 Reference Circuit Using an Active Antenna
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The supply voltage for VCC is 2.7 V ~ 3.6 V
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Ground all GND pins of the module
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Connect the RF_IN signal to the antenna; note the 50 Ω impedance matching
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Feed the antenna with external power supply
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The supply voltage for VBCKP is 1.7 V ~ 3.6 V
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Requirement for the odometer speed pulse: width ≥ 100 us, frequency ≤ 5K Hz
Active Low
VCC 2. 7 V~3.6V
VBCK P 1.7 V~3.6V
RF Short 50ohm Line
Figure 1-1 Reference Circuit Using an Active Antenna