User Manual
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V 1.0
2021-08-25
XDPP1100 technical reference manual
Digital power controller
Voltage control
vc_vavp_kfp kfp
kfp_real
F3db (kHz) vc_vavp_kfp kfp
kfp_real
F3db (kHz)
7
14
0.0001
0.43
23
224
0.0017
6.81
8
16
0.0001
0.49
24
256
0.0020
7.79
9
20
0.0002
0.61
25
320
0.0024
9.74
10
24
0.0002
0.73
26
384
0.0029
11.69
11
28
0.0002
0.85
27
448
0.0034
13.65
12
32
0.0002
0.97
28
512
0.0039
15.60
13
40
0.0003
1.21
29
640
0.0049
19.52
14
48
0.0004
1.46
30
768
0.0059
23.45
15
56
0.0004
1.70
31
na
na
bypass
The LPF outputs are summed to create the total droop voltage, vavp_total, which is further clamped by the
following registers to create vcontrol_vavp:
•
vc_vavp_clamp_pos
, which clamps the positive droop defined as decreasing voltage due to positive I
OUT
•
vc_vavp_clamp_neg
, which clamps the negative droop defined as increasing voltage due to negative I
OUT
5.5
Output summation and clamping
The final V
control
output is a sum of:
•
vcontrol_ramp, which is the output of the ramp generator
•
vcontrol_vavp, which results from the droop computations
•
fault_iout_cc_adj, which is the I
OUT
fault constant current voltage adjustment (discussed in
•
ishare_adj, which is the current sharing voltage adjustment (discussed in
The summation and clamping of the final V
control
is shown in
Figure 44
Final voltage summation and clamping
Subsequent to the summation, a final set of clamps is applied. The maximum and minimum clamp values can
be computed from PMBus commands according to Equations (5.14) and (5.15) and set via the following
registers:
•
vc_vcontrol_vout_max
according to Equation (5.14)
•
vc_vcontrol_vout_min
according to Equation (5.15)
𝑣𝑐_𝑣𝑐𝑜𝑛𝑡𝑟𝑜𝑙_𝑣𝑜𝑢𝑡_𝑚𝑎𝑥 =
𝑉𝑂𝑈𝑇_𝑀𝐴𝑋∗𝑉𝑂𝑈𝑇_𝑆𝐶𝐴𝐿𝐸_𝐿𝑂𝑂𝑃∗50
2
(24)
(5.14)
U12.3
vcontrol[14:0]
vcontrol_ramp[14:0]
U12.3
ishare_adj[11:0]
Loop 0 only, S9.3
fault_iout_cc_adj[13:0]
U11.3
vc_over_vout_max
vc_under_vout_min
S12.3
vcontrol_vavp[14:0]
S
-
+
-
+
S14.3
Clamp
vc_vcontrol_vout_max[7:0]
U12.+4
vc_vcontrol_vout_min[7:0]
U12.+4
