MCP3909 Microchip Technology, MCP3909 Datasheet - Page 23

• Manufacturer Part Number: MCP3909
• Description: Energy Metering IC with SPI Interface and Active Power Pulse Output
• Manufacturer: Microchip Technology

5.2
The MCP3909 devices contains three different serial
modes with data presented in 2's complement coding.
• Multiplier Output
• Dual Channel Output
• Filter Input
After entering any of these modes the active power
calculation block is still functional and presents output
pulses on F
TABLE 5-1:
© 2006 Microchip Technology Inc.
Note 1:
1 0 1 0 0 0 0 1
1 0 1 0 1 0 0 1
1 0 1 0 0 1 0 0
1 0 1 0 1 1 0 0
1 0 1 0 1 0 1 0
1 0 1 0 1 1 1 0
1 0 1 0 0 0 1 0
1 0 1 0 0 1 1 0
Command
D7......D0
Serial Mode Entry Codes
The active power frequency outputs F
Leaving the SDI (F1) and CS (F0) pins at a known state after serial communication will control the
frequency selection. The HPF pin controls the state of the HPF for the multiplier mode output and the out-
put pulses from the active power D to F block.
OUT0
, F
ENTRY CODES
OUT1
, and HF
Dual Channel Output Post HPF1
Dual Channel Output Pre HPF1
OUT
. For this reason,
Multiplier Output
Multiplier Output
Serial Mode
Filter Input
Filter Input
Filter Input
Filter Input
OUT0
, F
OUT1
, and HF
the F2, F1, F0 output frequency selection constant can
be changed with multiple command bytes for serial
mode entry.
The command bytes to enter these modes are
described in
Internal State of F2, F1, F0 Constants Frequency
OUT
F2
0
1
0
1
1
1
0
0
Selection During Serial Mode
remain active after serial mode entry.
Table
5-1.
F1 pin
F1 pin
F1 pin
F1 pin
F1
0
1
0
1
MCP3909
DS22025A-page 23
(1)
F0 pin
F0 pin
F0 pin
F0 pin
F0
1
1
1
1