Datasheet

LTC2977
71
2977fa
For more information www.linear.com/LTC2977
The data returned between bytes 72 and 237 of the previous
table is interpreted using Position_last and the following
table. The key to identifying byte 72 is to locate the DATA
corresponding to POSITION = Position_last in the next
table. Subsequent bytes are identified by decrementing
the value of POSITION. For example: If Position_last = 11
then the first data returned in byte position 72 of a block
read is Read_vin[15:8] followed by Read_vin[7:0] followed
by Mfr_status_2 of page 1. See Table 3.
Table 3. Interpreting Cyclical Loop
POSITION DATA
0 Read_vout0[7:0]
1 Read_vout0[15:8]
2 Status_vout0
3 Status_mfr0
4 Mfr_status_2_0[7:0]
5 Read_vout1[7:0]
6 Read_vout1[15:8]
7 Status_vout1
8 Status_mfr1
9 Mfr_status_2_1[7:0]
10 Read_vin[7:0]
11 Read_vin[15:8]
12 Status_vin
13 Read_vout2[7:0]
14 Read_vout2[15:8]
15 Status_vout2
16 Status_mfr2
17 Mfr_status_2_2[7:0]
18 Read_vout3[7:0]
19 Read_vout3[15:8]
20 Status_vout3
21 Status_mfr3
22 Mfr_status_2_3[7:0]
23 Read_temperature_1[7:0]
24 Read_temperature_1[15:8]
25 Status_temp
26 Read_vout4[7:0]
27 Read_vout4[15:8]
28 Status_vout4
29 Status_mfr4
30 Mfr_status_2_4[7:0]
31 Read_vout5[7:0]
32 Read_vout5[15:8]
33 Status_vout5
Table 3. Interpreting Cyclical Loop
POSITION DATA
34 Status_mfr5
35 Mfr_status_2_5[7:0]
36 Read_vout6[7:0]
37 Read_vout6[15:8]
38 Status_vout6
39 Status_mfr6
40 Mfr_status_2_6[7:0]
41 Read_vout7[7:0]
42 Read_vout7[15:8]
43 Status_vout7
44 Status_mfr7
45 Mfr_status_2_7[7:0]
Total Bytes = 46
The following table fully decodes a sample fault log read
to help clarify the cyclical nature of the operation.
MFR_FAULT_LOG DATA BLOCK CONTENTS
PREAMBLE INFORMATION
BYTE
NUMBER
DECIMAL
BYTE
NUMBER
HEX DATA DESCRIPTION
0 00 Position_last[7:0] = 11 Position of
Fault-Log Pointer
When Fault
Occurred.
1 01 Cyclic_data_valid_
count[7:0] = 160
Final 6 Bytes Of
Cyclic Data Not
Valid
2 02 SharedTime[7:0] 41-Bit Share-
Clock Counter
Value When Fault
Occurred. Counter
LSB Is in 200µs
Increments.
3 03 SharedTime[15:8]
4 04 SharedTime[23:16]
5 05 SharedTime[31:24]
6 06 SharedTime[39:32]
7 07 SharedTime[40]
8 08 Mfr_vout_peak0[7:0]
9 09 Mfr_vout_peak0[15:8]
10 0A Mfr_vout_min0[7:0]
11 0B Mfr_vout_min0[15:8]
12 0C Mfr_vout_peak1[7:0]
13 0D Mfr_vout_peak1[15:8]
14 0E Mfr_vout_min1[7:0]
15 0F Mfr_vout_min1[15:8]
PMBus COMMAND DESCRIPTION