MCHC908GR8AVFAE Freescale Semiconductor, MCHC908GR8AVFAE Datasheet - Page 73

• Manufacturer Part Number: MCHC908GR8AVFAE
• Description: IC MCU 8K FLASH 8MHZ 32-LQFP
• Manufacturer: Freescale Semiconductor
• Series: HC08r

Specifications of MCHC908GR8AVFAE

• Core Processor: HC08
• Core Size: 8-Bit
• Speed: 8MHz
• Connectivity: SCI, SPI
• Peripherals: LVD, POR, PWM
• Number Of I /o: 21
• Program Memory Size: 7.5KB (7.5K x 8)
• Program Memory Type: FLASH
• Ram Size: 384 x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 6x8b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 105°C
• Package / Case: 32-LQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -

4.8.3 Choosing a Filter
As described in
stability and reaction time of the PLL. The PLL is also dependent on reference frequency and supply
voltage.
Figure 4-10
the PLL are not critical, the three component filter network shown in
single capacitor, C
at various reference frequencies. For reference frequencies between the values listed in the table,
extrapolate to the nearest common capacitor value. In general, a slightly larger capacitor provides more
stability at the expense of increased lock time.
Freescale Semiconductor
shows two types of filter circuits. In low-cost applications, where stability and reaction time of
4.8.2 Parametric Influences on Reaction
F
1 MHz
2 MHz
3 MHz
4 MHz
5 MHz
6 MHz
7 MHz
8 MHz
f
, as shown in
RCLK
(A)
MC68HC908GR8A • MC68HC908GR4A Data Sheet, Rev. 5
CGMXFC
Table 4-4. Example Filter Component Values
V
SSA
Figure
C
F
8.2 nF
4.7 nF
3.3 nF
2.2 nF
1.8 nF
1.5 nF
1.2 nF
1 nF
C
F1
Figure 4-10. PLL Filter
4-10(A). Refer to
820 pF
470 pF
330 pF
220 pF
180 pF
150 pF
120 pF
100 pF
C
F2
Time, the external filter network is critical to the
Table 4-4
(B)
C
R
F1
CGMXFC
F1
Figure 4-10(B)
R
for recommended filter components
2k
2k
2k
2k
2k
2k
2k
2k
F1
Acquisition/Lock Time Specifications
V
SSA
C
F2
6.8 nF
5.6 nF
4.7 nF
3.9 nF
3.3 nF
2.7 nF
2.2 nF
18 nF
C
can be replaced by a
F
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