ML610Q409-NNNTBZ03A7 Rohm Semiconductor, ML610Q409-NNNTBZ03A7 Datasheet - Page 305

• Manufacturer Part Number: ML610Q409-NNNTBZ03A7
• Description: MCU 8BIT 16K FLASH 4CH 100-TQFP
• Manufacturer: Rohm Semiconductor
• Series: -r

Specifications of ML610Q409-NNNTBZ03A7

• Core Processor: nX-U8/100
• Core Size: 8-Bit
• Speed: 2MHz
• Connectivity: SSP, UART/USART
• Peripherals: LCD, Melody Driver, POR, PWM, WDT
• Number Of I /o: 22
• Program Memory Size: 16KB (8K x 16)
• Program Memory Type: FLASH
• Eeprom Size: -
• Ram Size: 1K x 8
• Voltage - Supply (vcc/vdd): 1.25 V ~ 3.6 V
• Data Converters: A/D 2x16b
• Oscillator Type: Internal
• Operating Temperature: -20°C ~ 70°C
• Package / Case: 100-TFQFP
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

The ratio between f
should ideally depend only on RT0.
Figure 21-14 shows, as an example of method, a timing chart of one cycle of conversion from analog value RT0 to a
digital value, that is, A/D conversion.
Basically, one A/D conversion cycle must consist of two steps, as shown in Figure 21-14. The reason for requiring two
steps is that the reference resistor and the thermistor must first be oscillated separately and then the ratio between the
oscillation frequencies of them is used, as described above.
In the example below, operation for these two steps is performed using the following combination:
•First step = RC oscillation with RS0 in Counter A reference mode
•Second step = RC oscillation with RT0 in Counter B reference mode
Besides this, there would be several possible A/D conversion methods.
In the above method, the operation time (gate time) for the second step fluctuates depending on the value of thermistor
RT0. To avoid the fluctuation of the operation time, using a method that uses the following combination is
recommended:
•First step = RC oscillation with RS0 in Counter B reference mode
•Second step = RC oscillation with RT0 in Counter A reference mode
A/D conversion procedure is explained below by taking Figure 21-14 as an example.
Figure 21-11 Temperature Characteristics of
RCCLK
(RS0)
Figure 21-13 Oscillation Characteristics of Reference Resistor
Reference Resistor
f
RCLK
(RT0) and f
Includes errors due to factors
other than RT0
RCCLK
Temperature T
(RS0) is equivalent to the above-mentioned A/D conversion value nT0 that
Temperature T
21-15
ML610Q407/ML610Q408/ML610Q409 User's Manual
f
(RT0)
R CCL K
Chapter 21 RC Oscillation Type A/D Converter
Figure 21-12 Oscillation Characteristics of
f
RCC LK
Ideal
Includes errors due to factors other
than RT0
(RS0) =
k
R CCLK
f
RC LK
·(CS0+CVR)·RS0
(RS0) =
Thermistor
k
RC CLK
1
Temperature T
·(CS0+CVR)·RT0
Ideal
1