Texas Instruments TRIS TMS37122 - Figure 16: Wake Pattern Detection State Diagram; 2.8.4.2 Transparent Mode

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Analog Front End IC TMS37122 - Reference Guide August ’01
or Passive Start Wake Pattern is received.
Figure 16: Wake Pattern Detection State Diagram
2.8.4.2 Transparent Mode
If the Wake Pattern A (Passive Entry) is detected, the circuit switches to Transparent Mode
(see Figure 16). In Transparent Mode the WAKE output is set, the internal signals CLKI and
EOBI are now available at the relating outputs (CLKA/M, EOBA). The watchdog for CLKI
is disabled, which means that the external Microcomputer has to take over the supervision and
Off-Mode
(Iquiet)
VRF>VWAKEA
for tWdly
(No_Wake Flag=0)
N
o modulation
during tWAIT
CLKI = ON
EOBI = ON
DEMOD = ON
Wait max.
for tWAIT
(Iact)
1st. EOBI detected
N
o valid or complete
WAKE PATTERN
during tWRX
Standby-
Mode
VWAKEA=ON
(Istby)
Receive
Wake Pattern
for max tWRX,
Check
Wake Pattern
(Iact)
EOBI = OFF,
Wait for
tTELEGR
(Iinit)
VRF
<
VWAKEA
WDEEN
= LOW
WDEEN
= LOW
TX = LOW and
WDEEN = HIGH
3DSTAT3A1.CW
CLKI missed
for twdg
tTELEGR
exceeded
CLKI
missed
for
twdg
CLKI =
OFF
CLKI missed
for twdg
CLKI missed
for twdg