U2270B Datasheet, PDF (9/13 Pages) TEMIC Semiconductors – Read / Write Base Station IC

U2270B
Application 3
This application is comparable to application 2 but alters
the operating frequency. This permits higher antenna
resonance tolerances and/or higher communication
distances. This application is preferred if the detecting
µC is close to the U2270B as an additional µC signal
controls the adequate operating frequency.
4x 1N4148
68 kW
75 kW
4.7 nF
100 kW
43 kW
V_S V_EXT DV_S V_Batt
1 nF
1.5 mH 82 W
Antenna
1N4148
180 pF
100 W
470 kW
RF
MS
COIL 2
CFE
U2270B
COIL 1
Standby
Input
C_IN
HIPASS
Output
OE
1.5 nF
C_HP
DGND GND
BC846
4.7 kW
1.5 kW
Figure 16.
22 mF
5V
47 nF
V_DD
GND
Micro-
controller
V_SS
12606
TELEFUNKEN Semiconductors
Rev. A3, 13-Dec-96
9 (13)