MC68HC908MR8CP Freescale Semiconductor, MC68HC908MR8CP Datasheet - Page 318

• Manufacturer Part Number: MC68HC908MR8CP
• Description: IC MCU 8K FLASH 8MHZ PWM 28-DIP
• Manufacturer: Freescale Semiconductor
• Series: HC08r

Specifications of MC68HC908MR8CP

• Core Processor: HC08
• Core Size: 8-Bit
• Speed: 8MHz
• Connectivity: SCI
• Peripherals: LVD, POR, PWM
• Number Of I /o: 12
• Program Memory Size: 8KB (8K x 8)
• Program Memory Type: FLASH
• Ram Size: 256 x 8
• Voltage - Supply (vcc/vdd): 4.5 V ~ 5.5 V
• Data Converters: A/D 4x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 28-DIP (0.600", 15.24mm)
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -

Analog-to-Digital Converter (ADC)
18.8.2 ADC Voltage In (ADVIN)
18.8.3 ADC External Connection
18.8.3.1 V
18.8.3.2 ANx
18.8.3.3 Grounding
Technical Data
318
REFH
ADVIN is the input voltage signal from one of the seven ADC channels
to the ADC module.
Both ac and dc current are drawn through V
form of current spikes required to supply charge to the capacitor array at
each successive approximation step. The dc current flows through the
internal resistor string. The best external component to meet both these
current demands is a capacitor in the 0.01 µF to 1 µF range with good
high-frequency characteristics. This capacitor is connected between
V
pins. Resistance in the path is not recommended because the dc current
will cause a voltage drop which could result in conversion errors.
Empirical data shows that capacitors from the analog inputs to V
improve ADC performance. 0.01 µF and 0.1 µF capacitors with good
high-frequency characteristics are sufficient. These capacitors must be
placed as close as possible to the package pins.
In cases where separate power supplies are used for analog and digital
power, the ground connection between these supplies should be at the
V
supplies if possible. The V
location.
REFH
SS
pin. This should be the only ground connection between these
and V
Analog-to-Digital Converter (ADC)
SS
and must be placed as close as possible to the package
SS
pin makes a good single-point ground
REFH
MC68HC908MR8 — Rev 4.1
. The ac current is in the
Freescale Semiconductor
RL