Infineon XDPP1100, Technical Reference Manual

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User Manual 11 of 562 V 1.0
2021-08-25
XDPP1100 technical reference manual
Digital power controller
Introduction
V
control
Internal reference voltage
V
errn
Error voltage
V
IMON
Voltage at the IMON pin
V
L
Inductor voltage
V
IN
Input voltage
V
OUT
Output voltage, Loop 0
V
PRIMARY
Primary-side voltage
V
RECT
Rectified voltage
VREF XDPP1100 input pin for voltage sensing
VRREF XDPP1100 input pin for voltage sensing
VRSEN XDPP1100 input pin for voltage sensing
VSEN XDPP1100 input pin for voltage sensing
V
SEN
Sensed voltage
1.3.3 Binary number format convention
Throughout this document in figures and text and in other XDPP1100-related documentation binary numbers
are often referred to as having the form Ux.y for unsigned numbers or Sx.y for signed numbers. The definitions
of these references are given below.
Ux.y indicates an unsigned number, with “ x ” indicating the bit position of the MSB and “ y ” indicating the bit
position of the LSB, each relative to the binary point. Sx.y indicates a signed number in two’s compliment
format with “ x ” and “ y ” defined as described above for the unsigned case. Figure 1 illustrates the x and y
meanings.
Figure 1 Binary number format x, y definitions
Some unsigned and signed number examples are given below.
•
U8.3 is an 11-bit unsigned number with 8 bits to the left of the binary point (MSB weight 2
7
) and 3 bits to the
right of the binary point (LSB weight 2
-3
).
•
U7.0 is a 7-bit unsigned number with 7 bits to the left of the binary point (MSB weight 2
6
) and 0 bits to the
right of the binary point (LSB weight 2
0
).
•
U-4.10 is a 6-bit unsigned number with all bits to the right of the binary point. The MSB is offset by 4 bits to
the right of the binary point (MSB weight 2
-5
) and the LSB is 10 bits to the right of the binary point (LSB
weight 2
-10
).
•
S9.3 is a 12-bit signed number with 9 bits to the left of the binary point (MSB weight 2
8
) and 3 bits to the right
of the binary point (LSB weight 2
-3
).
•
S8.-2 is a 6-bit signed number with all bits to the left of the binary point. The MSB is 8 bits to the left of the
binary point (MSB weight 2
7
) and the LSB is offset by 2 bits to the left of the binary point (LSB weight 2
2
).
. ... ...
Bit weight
X = MSB position
Y = LSB position
1 2 3 4 -3 -2 -1 0
0 -1 -2 -3 4 3 2 1
2
0
2
1
2
2
2
3
2
-1
2
-2
2
-3
2
-4