
17-2
ML63326 User's Manual
Chapter 17 Power Supply Circuit (POWER)
17.3 Power Supply Circuit Operation
The V
DDL
output of the power supply for the internal logic circuits is automatically switched
to the V
DD
level when the time base counter is reset, and changes to 1.7 V immediately after
the reset state is released. Further, the V
DDL
output is switched to the V
DD
level when ENOSC
(bit 1 of FCON) is set to "1", and returns to 1.7 V when ENOSC is set to "0".
The V
DD2
output of the LCD bias reference power supply is automatically switched to the V
DD
level when the time base counter is reset, and changes to the voltage (1.8V to 2.4 V) selected
by the display contrast register (DSPCNT) immediately after the reset state is released.
The V
DDH
output of the power supply for high-speed oscillation becomes about 1.2 V after
the time base counter is reset and while the high-speed oscillations have been stopped
(ENOSC = "0") because it is connected via V
DD2
and a diode. When the high-speed
oscillations are started (ENOSC = "1"), the voltage doubler circuit starts operating and V
DDH
becomes a voltage equal to about two times V
DD2
.
Figure 17-2 Power Supply Circuit Operation Waveforms
RESETS
(system reset)
Low-speed clock
oscillation output
ENOSC
V
DDH
RESET0 (time base
counter reset)
CPU start
Stop high-speed oscillation
Start of
high-speed oscillation
V
DDL
V
DD2
V
DD
V
DD
Approx. 1.7 V
Approx. 1.8 to 2.4 V
Approx. 1.7 V
Approx. 1.2 V
V
DD
32.768 kHz
Approx.
V
DD
¥
2
Approx. 125 ms
Approx. 1.2 V
Summary of Contents for ML63326
Page 3: ......
Page 13: ......
Page 14: ...Chapter 1 Overview 1 ...
Page 15: ......
Page 37: ...1 22 ML63326 User s Manual Chapter 1 Overview ...
Page 38: ...Chapter 2 CPU and Memory Spaces 2 ...
Page 39: ......
Page 50: ...CPU Control Functions Chapter 3 3 ...
Page 51: ......
Page 57: ...3 6 ML63326 User s Manual Chapter 3 CPU Control Functions ...
Page 58: ...Interrupt INT326 Chapter 4 4 ...
Page 59: ......
Page 71: ...4 12 ML63326 User s Manual Chapter 4 Interrupt INT326 ...
Page 72: ...Clock Generator Circuit OSC Chapter 5 5 ...
Page 73: ......
Page 83: ...5 10 ML63326 User s Manual Chapter 5 Clock Generator Circuit OSC ...
Page 84: ...Time Base Counter TBC Chapter 6 6 ...
Page 85: ......
Page 90: ...Timers TIMER Chapter 7 7 ...
Page 91: ......
Page 115: ...7 24 ML63326 User s Manual Chapter 7 Timers TIMER ...
Page 116: ...Chapter 8 8 100 Hz Timer Counter 100HzTC ...
Page 117: ......
Page 121: ...8 4 ML63326 User s Manual Chapter 8 100 Hz Timer Counter 100HzTC ...
Page 122: ...Chapter 9 9 Watchdog Timer WDT ...
Page 123: ......
Page 128: ...Chapter 10 10 Ports INPUT OUTPUT I O PORT ...
Page 129: ......
Page 170: ...Chapter 11 11 External Memory Transfer Function EXTMEM ...
Page 171: ......
Page 179: ...11 8 ML63326 User s Manual Chapter 11 External Memory Transfer Function EXTMEM ...
Page 180: ...Chapter 12 12 Melody Driver MELODY63K ...
Page 181: ......
Page 195: ...12 14 ML63326 User s Manual Chapter 12 Melody Driver MELODY63K ...
Page 196: ...13 Chapter 13 Voice Synthesis ...
Page 197: ......
Page 228: ...14 Chapter 14 Shift Register SFT ...
Page 229: ......
Page 236: ...15 Chapter 15 LCD Driver LCD ...
Page 237: ......
Page 250: ...16 Chapter 16 Battery Low Detect Circuit BLD ...
Page 251: ......
Page 255: ...16 4 ML63326 User s Manual Chapter 16 Battery Low Detect Circuit BLD ...
Page 256: ...Chapter 17 17 Power Supply Circuit POWER ...
Page 257: ......
Page 260: ...Appendixes ...
Page 261: ......
Page 321: ...Appendix 60 ML63326 User s Manual Appendix G ...