HD64F36077GHV Renesas Electronics America, HD64F36077GHV Datasheet - Page 407

• Manufacturer Part Number: HD64F36077GHV
• Description: 16BIT MCU FLASH 56K, SMD, LQFP64
• Manufacturer: Renesas Electronics America

Specifications of HD64F36077GHV

• No. Of I/o's: 47
• Ram Memory Size: 4KB
• Cpu Speed: 20MHz
• No. Of Timers: 4
• Digital Ic Case Style: LQFP
• Supply Voltage Range: 4.5V
• Core Size: 16bit
• Program Memory Size: 56KB
• Oscillator Type: External Only
• Controller Family/series: H8/300H
• Peripherals: ADC
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

19.3.2
LVDR (Reset by Low Voltage Detection) Circuit:
Figure 19.4 shows the timing of the operation of the LVDR circuit. The LVDR circuit is kept
enabled during the LSI's operation.
When the power-supply voltage falls below the Vreset voltage (the value selected by the LVDSEL
bit: Typ. = 2.3 V or 3.6 V), the LVDR circuit clears the LVDRES signal to 0, and resets prescaler
S. The low-voltage detection reset state remains in place until a power-on reset is generated. When
the power-supply voltage rises above the Vreset voltage (Typ. = 3.6 V) regardless of LVDSEL bit
setting) again, the LVDR circuit sets the LVDRES signal to 1 and prescaler S starts counting.
When 131,072 clock (φ) cycles have been counted, the internal reset signal is released. In this
case, the LVDSEL bit in LVDCR is initialized (the Vreset voltage: Typ. = 3.6 V) though the
VDDII bit is not initialized.
If the power supply voltage (Vcc) falls below Vpor = 100 mV, a power-on reset occurs.
RES
Vcc
PSS-reset
signal
OVF
Internal reset
signal
Low-Voltage Detection Circuit
Vpor
t
PWON
Figure 19.3 Operational Timing of Power-On Reset Circuit
PSS counter starts
Section 19 Band-Gap Circuit, Power-On Reset, and Low-Voltage Detection Circuits
131,072 cycles
Reset released
Rev. 1.00 Sep. 16, 2005 Page 377 of 490
REJ09B0216-0100
Vss
Vss