Datasheet

Analog Integrated Circuit Device Data
Freescale Semiconductor 94
MC34708
Functional Block Description
The MC34708 contains registers which hold control and status information. The register map and the description of each register
can be found in the SPI/I2C Register Map section. The details of some important control bits are described as follows.
7.8.4.6 Control Functions
7.8.4.6.1 Timing of the Switching Action (WAIT BIT)
If the WAIT bit is '1' when the Attach interrupt bit is set, the MC34708 waits for a WAIT time before turning on the switches. The
WAIT time is programmed by the Switching Wait bits in the Timing Set 2 register. If the WAIT bit is '0' when the Attach interrupt
is generated, then the MC34708 will not turn on the switches until the WAIT bit is set to '1' by the SPI. Both cases are shown in
Figure 25.
Table 92. Timing Delays for PSTI Circuit
Characteristics noted under conditions BP = 3.6 V, V
BUS
= 5.0 V, - 40 C  T
A
 85 C, unless otherwise noted. Typical values
at BP = 3.6
V and T
A
= 25 °C under nominal conditions, unless otherwise noted.
Symbol Characteristic Min Typ Max Unit Notes
Switching Delay
t
D
t1 - t0 (t
D
in Default Value is TD = 0100)
•TD = 0000
•TD = 0001
•TD = 0010
•TD = 0011
•TD = 0100
• ...
•TD = 1111
-
-
-
-
-
...
-
100
200
300
400
500
...
1600
-
-
-
-
-
...
-
ms
t
SW
t2 - t1
20 - - ms
t
SW
t3 - t2
20 - - ms
t
SW
t4 - t1
100 - - ms
t
SW
t6 - t3
100 - - ms