ST72T774J9B1 STMicroelectronics, ST72T774J9B1 Datasheet - Page 117

• Manufacturer Part Number: ST72T774J9B1
• Manufacturer: STMicroelectronics

Specifications of ST72T774J9B1

• Cpu Family: ST7
• Device Core Size: 8b
• Frequency (max): 24MHz
• Interface Type: I2C/USB
• Program Memory Type: EPROM
• Program Memory Size: 60KB
• Total Internal Ram Size: 1KB
• # I/os (max): 31
• Number Of Timers - General Purpose: 1
• Operating Supply Voltage (typ): 5V
• Operating Supply Voltage (max): 5.5V
• Operating Supply Voltage (min): 4V
• On-chip Adc: 1-chx8-bit
• On-chip Dac: 1-chx8-bit
• Instruction Set Architecture: CISC
• Operating Temp Range: 0C to 70C
• Operating Temperature Classification: Commercial
• Mounting: Through Hole
• Pin Count: 42
• Package Type: SPDIP
• Lead Free Status / Rohs Status: Specific Sites Compliant

PWM/BRM Outputs (Cont’d)
PWM/BRM Outputs
The PWM/BRM outputs are assigned to dedicated
pins.
The RC filter time must be higher than TCPUx64.
Figure 70. Typical PWM Output Filter
Figure 71. PWM Simplified Voltage Output After Filtering
OUTPUT
STAGE
VOLTAGE
VOLTAGE
PWMOUT
PWMOUT
OUTPUT
OUTPUT
V
V
V
V
0V
0V
0V
0V
DD
DD
DD
DD
"CHARGE"
"CHARGE"
"DISCHARGE"
R
ext
"DISCHARGE"
OUTPUT
VOLTAGE
C
ext
"CHARGE"
Table 27. 6-Bit PWM Ripple After Filtering
With RC filter (R=1K ),
f
V
PWM Duty Cycle 50%
R=Rext.
CPU
DD
C
"CHARGE"
ext
0.128
1.28
12.8
= 5V
= 8 MHz
(µF)
"DISCHARGE"
ST72774/ST727754/ST72734
"DISCHARGE"
V RIPPLE (mV)
0.78
7.8
78
V
ripple
V ripple (mV)
(mV)
V
V
OUTAVG
OUTAVG
VR01956
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