mlx90109 Melexis Company, mlx90109 Datasheet - Page 11

• Manufacturer Part Number: mlx90109
• Description: 125khz Rfid Transceiver
• Manufacturer: Melexis Company

10 Typical configuration: READ/WRITE ON/OFF keying (FDX-B100)
The basic principle is to switch the voltage on MODU between 0V and V
maximum amplitude in less than 3 periods when MODU is stepped down from V
power-down (set V
antenna’s quality factor Q
microcontroller could be used to decrease the fall time (refer to the application note MLX90109 “100%
modulation (ON/OFF Keying)”.
Note : Care should be taken to the capacitor C1 which may reduce the fall time.
3901090109
Rev 008
10.1 Application diagram
MODU
up to V
ant
. For fast protocols, an additional drain resistor on MODU controlled by the
DD
) will let the antenna fade-out with a time constant, depending on the
Page 11 of 15
125kHz RFID Transceiver
DD
. The antenna will reach its
DD
MLX90109
to V
SS
. Setting the chip in
Data Sheet
Jun/06