STM3220G-SK/IAR STMicroelectronics, STM3220G-SK/IAR Datasheet - Page 84

• Manufacturer Part Number: STM3220G-SK/IAR
• Description: DEV KIT STM32F207ZG KICKSTART
• Manufacturer: STMicroelectronics
• Series: IAR Kickstartr
• Type: MCUr

Specifications of STM3220G-SK/IAR

• Contents: Hardware, Software and Documentation
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• For Use With/related Products: STM32F207
• Other names: 497-11404

Electrical characteristics
5.3.11
Table 31.
1. Guaranteed by design, not tested in production.
84/163
MODEPER * INCSTEP
Symbol
f
md
Mod
PLL spread spectrum clock generation (SSCG) characteristics
The spread spectrum clock generation (SSCG) feature allows to reduce electromagnetic
interferences (see
SSCG parameters constraint
Equation 1
The frequency modulation period (MODEPER) is given by the equation below:
Equation 2
Equation 2 allows to calculate the increment step (INCSTEP):
An amplitude quantization error may be generated because the linear modulation profile is
obtained by taking the quantized values (rounded to the nearest integer) of MODPER and
INCSTEP. As a result, the achieved modulation depth is quantized. The percentage
quantized modulation depth is given by the following formula:
Figure 34
down spread modes, where:
F0 is f
T
md is the modulation depth.
mode
md
and
PLL_OUT
is the modulation period.
INCSTEP
quantized
Figure 35
Table 37: EMI
nominal.
%
=
=
round
show the main PLL output clock waveforms in center spread and
Peak modulation depth
Modulation frequency
(
MODEPER
MODEPER INCSTEP
[
Doc ID 15818 Rev 6
Parameter
(
(
2
characteristics). It is available only on the main PLL.
15
–
1
) md
×
=
×
round f
×
[
f
VCO_OUT
PLL_IN
×
100
⁄
(
)
4
×
⁄
(
×
5
100 5
)
f
Min
0.5
Mod
⁄
STM32F205xx, STM32F207xx
-
-
(
(
×
2
)
15
]
×
–
MODEPER
1
Typ
) f
-
-
-
×
VCO_OUT
Max
2
15
10
2
)
−1
]
(1)
)
Unit
KHz
dec
dec