HD64F2623FA20J Renesas Electronics America, HD64F2623FA20J Datasheet - Page 637

• Manufacturer Part Number: HD64F2623FA20J
• Description: IC H8S MCU FLASH 256K 100-QFP
• Manufacturer: Renesas Electronics America
• Series: H8® H8S/2600r

Specifications of HD64F2623FA20J

• Core Processor: H8S/2600
• Core Size: 16-Bit
• Speed: 20MHz
• Connectivity: CAN, SCI, SmartCard
• Peripherals: POR, PWM, WDT
• Number Of I /o: 53
• Program Memory Size: 256KB (256K x 8)
• Program Memory Type: FLASH
• Ram Size: 12K x 8
• Voltage - Supply (vcc/vdd): 3 V ~ 3.6 V
• Data Converters: A/D 16x10b; D/A 2x8b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 100-QFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -

Permissible Signal Source Impedance: H8S/2626 Group and H8S/2623 Group analog input is
designed so that conversion precision is guaranteed for an input signal for which the signal source
impedance is 10 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 10 k , charging may be insufficient and it may not be possible to guarantee
the A/D conversion precision.
However, if a large capacitance is provided externally, the input load will essentially comprise
only the internal input resistance of 10 k , and the signal source impedance is ignored.
However, since 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).
When converting a high-speed analog signal, a low-impedance buffer should be inserted.
Influences on Absolute Precision: Adding capacitance results in coupling with GND, and
therefore noise in GND may adversely affect absolute precision. Be sure to make the connection
to an electrically stable GND such as AVSS.
Care is also required to insure that filter circuits do not communicate with digital signals on the
mounting board, so acting as antennas.
Sensor input
Sensor output
impedance
to 5 k
Low-pass
filter C
to 0.1 µF
Figure 16.11 Example of Analog Input Circuit
H8S/2626 Group or
H8S/2623 Group
C
15 pF
in
=
Rev. 5.00 Jan 10, 2006 page 611 of 1042
A/D converter
equivalent circuit
10 k
Section 16 A/D Converter
REJ09B0275-0500
20 pF