MC908AZ32ACFU Freescale Semiconductor, MC908AZ32ACFU Datasheet - Page 97

no-image

MC908AZ32ACFU

Manufacturer Part Number
MC908AZ32ACFU
Description
IC MCU 32K FLASH 8.4MHZ 64-QFP
Manufacturer
Freescale Semiconductor
Series
HC08r
Datasheet

Specifications of MC908AZ32ACFU

Core Processor
HC08
Core Size
8-Bit
Speed
8MHz
Connectivity
CAN, SCI, SPI
Peripherals
LVD, POR, PWM
Number Of I /o
40
Program Memory Size
32KB (32K x 8)
Program Memory Type
FLASH
Eeprom Size
512 x 8
Ram Size
1K x 8
Voltage - Supply (vcc/vdd)
4.5 V ~ 5.5 V
Data Converters
A/D 15x8b
Oscillator Type
Internal
Operating Temperature
-40°C ~ 85°C
Package / Case
64-QFP
Lead Free Status / RoHS Status
Contains lead / RoHS non-compliant

Available stocks

Company
Part Number
Manufacturer
Quantity
Price
Part Number:
MC908AZ32ACFU
Manufacturer:
FREESCALE
Quantity:
3
Part Number:
MC908AZ32ACFU
Manufacturer:
Freescale Semiconductor
Quantity:
10 000
Part Number:
MC908AZ32ACFU
Manufacturer:
MOTOROLA/摩托罗拉
Quantity:
20 000
Part Number:
MC908AZ32ACFUE
Manufacturer:
Freescale Semiconductor
Quantity:
10 000
Part Number:
MC908AZ32ACFUE
Manufacturer:
FREESCALE
Quantity:
20 000
Part Number:
MC908AZ32ACFUER
Manufacturer:
Freescale Semiconductor
Quantity:
10 000
8.3.3 Base Clock Selector Circuit
This circuit is used to select either the crystal clock, CGMXCLK, or the VCO clock, CGMVCLK, as the
source of the base clock, CGMOUT. The two input clocks go through a transition control circuit that waits
up to three CGMXCLK cycles and three CGMVCLK cycles to change from one clock source to the other.
During this time, CGMOUT is held in stasis. The output of the transition control circuit is then divided by
two to correct the duty cycle. Therefore, the bus clock frequency, which is one-half of the base clock
frequency, is one-fourth the frequency of the selected clock (CGMXCLK or CGMVCLK).
The BCS bit in the PLL control register (PCTL) selects which clock drives CGMOUT. The VCO clock
cannot be selected as the base clock source if the PLL is not turned on. The PLL cannot be turned off if
the VCO clock is selected. The PLL cannot be turned on or off simultaneously with the selection or
deselection of the VCO clock. The VCO clock also cannot be selected as the base clock source if the
factor L is programmed to a 0. This value would set up a condition inconsistent with the operation of the
PLL, so that the PLL would be disabled and the crystal clock would be forced as the source of the base
clock.
8.3.4 CGM External Connections
In its typical configuration, the CGM requires seven external components. Five of these are for the crystal
oscillator and two are for the PLL.
The crystal oscillator is normally connected in a Pierce oscillator configuration, as shown in
Figure 8-3
circuitry. The oscillator configuration uses five components:
Freescale Semiconductor
Crystal, X
Fixed capacitor, C
Tuning capacitor, C
Feedback resistor, R
Series resistor, R
shows only the logical representation of the internal components and may not represent actual
*R
S
1
can be 0 (shorted) when used with higher-frequency crystals. Refer to manufacturer’s data.
SIMOSCEN
S
C
1
1
(optional)
2
B
(can also be a fixed capacitor)
R
X
1
B
Figure 8-3. CGM External Connections
MC68HC908AZ32A Data Sheet, Rev. 2
R
C
S
2
*
CGMXCLK
C
F
Functional Description
C
BYP
V
DD
Figure
8-3.
97

Related parts for MC908AZ32ACFU