SI3232 SILABS [Silicon Laboratories], SI3232 Datasheet - Page 35

• Manufacturer Part Number: SI3232
• Description: DUAL PROGRAMMABLE CMOS SLIC WITH LINE MONITORING
• Manufacturer: SILABS [Silicon Laboratories]

#
1
2
3
4
5
I
I
I
I
Q2
Q5
Q6
Q1
LOOP CLOSURE
LOOP OPEN
LOOP OPEN
RING-GND
RING-GND
Loop
State
Processor
Signal
Input
LFS
Table 21. State Transitions During Ground Key Detection
I
LONG
(FWD-ACTIVE)
(FWD-ACTIVE)
(FWD-ACTIVE)
Figure 15. Ground Key Detection Circuitry
(TIP-OPEN)
(TIP-OPEN)
LINEFEED
LFS = 3
LFS = 3
LFS = 1
LFS = 1
LFS = 1
LONGLPF
State
Digital
LPF
LONGHITH
Preliminary Rev. 0.96
Ground Key
Threshold
I
LOOP
LONGLOTH
–
+
22
22
21
0
0
(mA) I
LONG
Debounce
–11
–11
LONGDBI
0
0
0
Filter
(mA)
LCR
0
1
1
1
0
LONGHI
Interrupt
LONGHI
LONGE
Logic
0
1
1
0
0
Si3232
CMHIGH
0
0
1
0
0
LONGS
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