STPM14 STMicroelectronics, STPM14 Datasheet - Page 30

• Manufacturer Part Number: STPM14
• Description: (STPM11 - STPM14) Single phase energy metering IC
• Manufacturer: STMicroelectronics

Theory of operation
Figure 21. Timing for writing configuration and mode bits
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The same procedure should be applied for the mode signals, but in this case the 6-bits
address must be taken from the
The lsb of command is also called EXE bit because instead of data bit value, the
corresponding serial clock pulse is used to generate the necessary latching signal. In this
way the writing mechanism does not need the measurement clock in order to operate, which
makes the operation of CFGI module of STPM1X completely independent from the rest of
the device logic except from the signal POR.
Commands for changing system signals should be sent during active signals SCS and SYN-
NP as it is shown in the
active signals SCS and SYN-NP.
t
t
t
t4: SDA value is stable and shifted into the device
t
t
t
t
t
t
1
2
3
3
3
5
6
8
9
: data value is placed in SDA
: end of CFGI writing
: CFGI enters idle state
→ t
→ t
→ t
→ t
→ t
→ t
2
3
5
5
6
7
: 1 bit Data value
: 6 bits address of the destination latch
: 1 bit EXE command
(>30ns): CFGI out of idle state
(>30ns): CFGI enabled for write operation
(>10µs): writing Clock period
Figure 19.
Table 14.
-. A string of commands can be send within one period of
.
STPM11/12/13/14