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Analog Front End IC TMS37122 - Reference Guide
August ’01
The LF Transmission Mode can also be entered directly from the OFF Mode. For this purpose
the TX input must be set to high before the WDEEN is set. Releasing TX while WDEEN =
high will switch to Transparent Mode. Next activation of TX activates the FSK Modulator.
Figure 18: State Diagram of LF Transmission Mode
2.10
Configuration Memory
2.10.1 Memory Organisation
The TMS37122 EEPROM Configuration Memory is organized by 3 rows and 5 nibbles. Each
nibble has 4 bits (see Figure 19). The Configuration Memory can be programmed and read
via Test/Trimming Interface. Programming and reading must be done nibble by nibble using
test mode PTx04 and PTx07.
OFF
(Iquiet)
WDEEN
= LOW
WDEEN =
HIGH
WDEEN
= LOW
3DSTAT5.CH4
Wdg. = OFF
WAKE = High
EOBA = ON
CLKA = ON
(Iact)
TX = HIGH and
WDEEN = HIGH
WAIT
TX=
LOW
TX=
HIGH
TX = LOW
and
WDEEN
=HIGH
TX =HIGH
CLKM=ON,
Start Oscillation
WDEEN = LOW
WDEEN
= HIGH
WDEEN = LOW