HD64F3664H Renesas Electronics America, HD64F3664H Datasheet - Page 316

• Manufacturer Part Number: HD64F3664H
• Description: IC H8 MCU FLASH 32K 64QFP
• Manufacturer: Renesas Electronics America
• Series: H8® H8/300H Tinyr

Specifications of HD64F3664H

• Core Processor: H8/300H
• Core Size: 16-Bit
• Speed: 16MHz
• Connectivity: I²C, SCI
• Peripherals: PWM, WDT
• Number Of I /o: 29
• Program Memory Size: 32KB (32K x 8)
• Program Memory Type: FLASH
• Ram Size: 2K x 8
• Voltage - Supply (vcc/vdd): 3 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: External
• Operating Temperature: -20°C ~ 75°C
• Package / Case: 64-QFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -

Section 16 A/D Converter
16.6
16.6.1
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 kΩ 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 kΩ, 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 kΩ, 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/µs or greater) (see figure 16.6). When converting a high-speed
analog signal or converting in scan mode, a low-impedance buffer should be inserted.
16.6.2
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. 6.00 Mar. 24, 2006 Page 286 of 412
REJ09B0142-0600
Usage Notes
Permissible Signal Source Impedance
Influences on Absolute Accuracy
Sensor input
Figure 16.6 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