71m6511h-igtr Maxim Integrated Products, Inc., 71m6511h-igtr Datasheet - Page 66

• Manufacturer Part Number: 71m6511h-igtr
• Description: Single-phase Energy Meter Ic
• Manufacturer: Maxim Integrated Products, Inc.

CE Front End Data (Raw Data)
Access to the raw data provided by the AFE is possible by reading addresses 0 through 7, as listed below.
CE Status Word
Since the CE_BUSY interrupt occurs at 2520.6Hz (or at 3276.8Hz when MUX_DIV = 2), it is desirable to minimize the
computation required in the interrupt handler of the MPU. The MPU can read CESTATUS at every CE_BUSY interrupt.
The CE Status Word is useful for generating early warnings to the MPU. It contains sag warnings for phase A, as well as F0,
the derived clock operating at the fundamental input frequency. CESTATUS provides information about the status of voltage
and input AC signal frequency, which are useful for generating an early power fail warning to initiate necessary data storage.
CESTATUS represents the status flags for the preceding CE code pass (CE_BUSY interrupt).
Note: The CE does not store sag alarms from one code pass to the next. CESTATUS is refreshed at every CE_BUSY
interrupt and remains valid for up to 100µs after the CE_BUSY interrupt occurs. Unsynchronized read operations of
CESTATUS will yield unreliable results.
The significance of the bits in CESTATUS is shown in the table below:
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CESTATUS
Address
31-29
[bit]
24-0
28
27
26
25
0x51
CE
RESERVED
RESERVED
Not Used
Not Used
CESTATUS
SAG_A
Name
Name
F0
Address (HEX)
Description
These unused bits will always be zero.
F0 is a square wave at the exact fundamental input frequency.
Normally zero. Becomes one when VA remains below SAG_THR for SAG_CNT
samples. Will not return to zero until VA rises above SAG_THR.
These unused bits will always be zero.
00
01
02
03
04
05
06
07
Description
See description of CE status word below
© 2005-2007 TERIDIAN Semiconductor Corporation
CE RAM Locations
TEMP
Name
VA
IA
IB
--
-
-
-
Description
Phase A current
Phase A voltage
Phase B current
Reserved
Reserved
Reserved
Temperature
Reserved
Single-Phase Energy Meter IC
71M6511/71M6511H
DATA SHEET
AUGUST 2007
V2.6