HD64F3672FPV Renesas Electronics America, HD64F3672FPV Datasheet - Page 240

• Manufacturer Part Number: HD64F3672FPV
• Description: IC H8/3672 MCU FLASH 64LQFP
• Manufacturer: Renesas Electronics America
• Series: H8® H8/300H Tinyr

Specifications of HD64F3672FPV

• Core Processor: H8/300H
• Core Size: 16-Bit
• Speed: 16MHz
• Connectivity: SCI
• Peripherals: PWM, WDT
• Number Of I /o: 26
• Program Memory Size: 16KB (16K x 8)
• Program Memory Type: FLASH
• Ram Size: 2K x 8
• Voltage - Supply (vcc/vdd): 3 V ~ 5.5 V
• Data Converters: A/D 4x10b
• Oscillator Type: Internal
• Operating Temperature: -20°C ~ 75°C
• Package / Case: 64-LQFP
• For Use With: R0K436079S000BE - KIT DEV FOR H8/36079 W/COMPILER
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -

Section 14 A/D Converter
14.6
14.6.1
This LSI's analog input is designed such that conversion accuracy is guaranteed for an input signal
for which the signal source impedance is 5 k or less. This specification is provided to enable the
A/D converter's sample-and-hold circuit input capacitance to be charged within the sampling time;
if the sensor output impedance exceeds 5 k , charging may be insufficient and it may not be
possible to guarantee A/D conversion accuracy. However, for A/D conversion in single mode with
a large capacitance provided externally, the input load will essentially comprise only the internal
input resistance of 10 k , and the signal source impedance is ignored. However, as a low-pass
filter effect is obtained in this case, it may not be possible to follow an analog signal with a large
differential coefficient (e.g., 5 mV/ s or greater) (see figure 14.6). When converting a high-speed
analog signal or converting in scan mode, a low-impedance buffer should be inserted.
14.6.2
Adding capacitance results in coupling with GND, and therefore noise in GND may adversely
affect absolute accuracy. Be sure to make the connection to an electrically stable GND.
Care is also required to ensure that filter circuits do not interfere with digital signals or act as
antennas on the mounting board.
Rev.4.00 Nov. 02, 2005 Page 214 of 304
REJ09B0143-0400
Usage Notes
Permissible Signal Source Impedance
Influences on Absolute Accuracy
Sensor input
Figure 14.6 Analog Input Circuit Example
Sensor output
impedance
to 5 k
Low-pass
filter
C to 0.1 F
This LSI
C
15 pF
in
=
A/D converter
equivalent circuit
10 k
20 pF