UPD70F3737GC-UEU-AX Renesas Electronics America, UPD70F3737GC-UEU-AX Datasheet - Page 455

• Manufacturer Part Number: UPD70F3737GC-UEU-AX
• Description: MCU 32BIT V850ES/JX3-L 100-LQFP
• Manufacturer: Renesas Electronics America
• Series: V850ES/Jx3-Lr

Specifications of UPD70F3737GC-UEU-AX

• Package / Case: *
• Voltage - Supply (vcc/vdd): 2.2 V ~ 3.6 V
• Operating Temperature: -40°C ~ 85°C
• Speed: 20MHz
• Number Of I /o: 84
• Core Processor: RISC
• Program Memory Type: FLASH
• Ram Size: 8K x 8
• Program Memory Size: 128KB (128K x 8)
• Data Converters: A/D 12x10b, D/A 2x8b
• Oscillator Type: Internal
• Peripherals: DMA, LVD, PWM, WDT
• Connectivity: CSI, EBI/EMI, I²C, UART/USART
• Core Size: 32-Bit
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -

(9) Standby mode
(10) High-speed conversion mode
(11) A/D conversion time
(12) Variation of A/D conversion results
(13) A/D conversion result hysteresis characteristics
Because the A/D converter stops operating in the STOP mode, conversion results are invalid, so power
consumption can be reduced. Operations are resumed after the STOP mode is released, but the A/D
conversion results after the STOP mode is released are invalid. When using the A/D converter after the STOP
mode is released, before setting the STOP mode or releasing the STOP mode, clear the ADA0M0.ADA0CE bit
to 0 then set the ADA0CE bit to 1 after releasing the STOP mode.
In the IDLE1, IDLE2, or subclock operation mode, operation continues. To lower the power consumption,
therefore, clear the ADA0M0.ADA0CE bit to 0. In the IDLE1 and IDLE2 modes, since the analog input voltage
value cannot be retained, the A/D conversion results after the IDLE1 and IDLE2 modes are released are invalid.
The results of conversions before the IDLE1 and IDLE2 modes were set are valid.
In the high-speed conversion mode, rewriting of the ADA0M0, ADA0M2, ADA0S, ADA0PFM, and ADA0PFT
registers and trigger input during the stabilization time are prohibited.
A/D conversion time is the total time of stabilization time, conversion time, wait time, and trigger response
time (for details of these times, refer to Table 13-2 Conversion Time Selection in Normal Conversion
Mode (ADA0HS1 Bit = 0) and Table 13-3 Conversion Time Selection in High-Speed Conversion Mode
(ADA0HS1 Bit = 1)).
During A/D conversion in the normal conversion mode, if the ADA0M0, ADA0M2, ADA0S, ADA0PFM, and
ADA0PFT registers are written or a trigger is input, reconversion is carried out. However, if the stabilization
time end timing conflicts with the writing to these registers, or if the stabilization time end timing conflicts with
the trigger input, the stabilization time of 64 clocks is reinserted.
If a conflict occurs again with the reinserted stabilization time end timing, the stabilization time is reinserted.
Therefore do not set the trigger input interval and control register write interval to 64 clocks or below.
The results of the A/D conversion may vary depending on the fluctuation of the supply voltage, or may be
affected by noise. To reduce the variation, take counteractive measures with the program such as averaging
the A/D conversion results.
The successive comparison type A/D converter holds the analog input voltage in the internal sample & hold
capacitor and then performs A/D conversion. After the A/D conversion has finished, the analog input voltage
remains in the internal sample & hold capacitor. As a result, the following phenomena may occur.
• When the same channel is used for A/D conversions, if the voltage is higher or lower than the previous A/D
• When switching the analog input channel, hysteresis characteristics may appear where the conversion
conversion, then hysteresis characteristics may appear where the conversion result is affected by the
previous value. Thus, even if the conversion is performed at the same potential, the result may vary.
result is affected by the previous channel value. This is because one A/D converter is used for the A/D
conversions. Thus, even if the conversion is performed at the same potential, the result may vary.
Preliminary User’s Manual U18953EJ1V0UD
CHAPTER 13 A/D CONVERTER
455