HD6477021X20V Renesas Electronics America, HD6477021X20V Datasheet - Page 183

• Manufacturer Part Number: HD6477021X20V
• Description: MCU 5V 32K PB-FREE 100-TQFP
• Manufacturer: Renesas Electronics America
• Series: SuperH® SH7020r

Specifications of HD6477021X20V

• Core Processor: SH-1
• Core Size: 32-Bit
• Speed: 20MHz
• Connectivity: EBI/EMI, SCI
• Peripherals: DMA, POR, PWM, WDT
• Number Of I /o: 32
• Program Memory Size: 32KB (32K x 8)
• Program Memory Type: OTP
• Ram Size: 1K x 8
• Voltage - Supply (vcc/vdd): 4.5 V ~ 5.5 V
• Oscillator Type: Internal
• Operating Temperature: -20°C ~ 75°C
• Package / Case: 100-TQFP, 100-VQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Data Converters: -

For the signal output shown by solid lines, DRAM data may not be held. Therefore, when DRAM
data must be held after reset, take one of the coutermeasures described as follows.
1. When resetting manually, do this in watchdog timer (WDT) condition.
2. Even if the Low width of RAS becomes as short as 1.5 tcyc as shown above, use with a
3. Even in case the Low width of RAS has become 1.5 tcyc, proceed by using the external circuit
A0 to A21
A0 to A21
frequency that satisfies the DRAM standard (tRAS).
so that a RAS signal with a Low width of 2.5 tcyc is input in the DRAM (in case the Low
width of RAS is higher than 2.5 tcyc, operate so that the current waveform is input in the
DRAM).
RES
RAS
CAS
RES
RAS
CAS
RD
CK
CK
RD
RES latch
timing
RES latch
Figure 8.40 Long - pitch Mode Read (1)
Figure 8.41 Long - pitch Mode Read (2)
timing
Manual reset
Manual reset
Tp
Tp
Row address
Row address
Tr
Tr
Colum address
FFFF
Tc1
Tc1
FFFF
Tc2
Tc2
RENESAS 163