MC33884 Datasheet, PDF (14/20 Pages) Motorola, Inc – Switch Monitor Interface

MC33884
DESCRIPTION (Continued)
WT[2:1] — Wake–Up Time
These bits let the device assert an external interrupt (INTB) at the following intervals during Polling mode (MOD2=MOD1=1).
Wake–Up Delay Prescales
WT[2:1]
00
Multiplier
Selected
512+1
Wake–Up Interrupt, tWAKE (ms)
[tDETECT (2.8ms typ.) * Multiplier]
2400 – 3200
01
256+1
1200 – 1600
10
128+1
600 – 750
11
64+1
290 – 360
CP[4:1] — Configure Programmable Switch
Configure the programmable inputs SP[4:1] to detect either an external switch–to–ground (internal current source) or an external
switch–to–battery (internal current sink). Note that this configuration may be entered in any of the three valid Operating Modes
(see MOD[2:1]) within the Run command.
Programmable Switch Bit Definition
CPx
External Switch to:
0
Ground
1
Battery
Tri–State Command
This command places an external switch into a “Tri–State” condition, essentially disconnecting the wetting current (if the switch
is metallic) and the sustain current. The internal input–threshold comparator is still internally connected to its external pin. This
command does not change the mode of operation (e.g., a Tri–State command received while in Polling mode leaves the part in
that mode). Note that the Tri–State register clears all bits to [0] (all inputs in Tri–State) in response to a hardware reset; all inputs
also remain in Tri–State after exiting the Sleep mode.
MSB
Bit
LSB
Bit
Command
16 15 14 13 12 11 10 9
8
7
654
3
2
1
Tri–State
0 0 1 1 TG6 TG5 TG4 TG3 TG2 TG1 TP4 TP3 TP2 TP1 TB2 TB1
RESET VALUES:
Tri–State Register
— ——— 0
0
0
0
0
0
000
0
0
0
TG[6:1] — Tri–State Switch–to–Ground
TB[2:1] — Tri–State Switch–to–Battery
TP[4:1] — Tri–State Programmable Switch
Tri–State Bit Definition
TGx, TBx, TPx
Input Configured to:
0
Input Disabled [DEFAULT]
1
Input Enabled
14
MOTOROLA TSG IC DEVICE DATA