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11
5. 3.3V Generator Circuit (Step-down DC-DC CONVERTER -3)
When IC9001 enters the wake-up mode and the WAKE(INT) signal is output from the system controller section, the Step-down DC-DC CONVERTER Circuit-3 inside
IC9001 starts up. This circuit is a step-down DC-DC converter circuit consisting of L9004, C9008, C9040 and the step-down circuit inside IC9001. This circuit operates as
follows. The step-down DC-DC converter circuit-3 controls the duty ratio of the PWM waveform which is output from pin-3 [VO3], with monitoring the voltage input to pin-18
[FB3] of IC9001. By this operation, the step-down circuit works, and the 3.3V voltage is generated and supplied to the unit as 3.3V, 3.3V_HDD and 3.3V_A voltage.
IC9001 starts up. This circuit is a step-down DC-DC converter circuit consisting of L9004, C9008, C9040 and the step-down circuit inside IC9001. This circuit operates as
follows. The step-down DC-DC converter circuit-3 controls the duty ratio of the PWM waveform which is output from pin-3 [VO3], with monitoring the voltage input to pin-18
[FB3] of IC9001. By this operation, the step-down circuit works, and the 3.3V voltage is generated and supplied to the unit as 3.3V, 3.3V_HDD and 3.3V_A voltage.
One Point:
A voltage value of 3.3V voltage changes depending on the operation mode shown in Table.2-4. As shown in Table.2-4, when HDD turns OFF, the step-down DC-DC converter
circuit-3 generates 3.1 [V] to realize lower power consumption.
circuit-3 generates 3.1 [V] to realize lower power consumption.
Table.2-4 3.3V voltage
Voltage Name
HDD ON
HDD OFF
Remark
3.3V
3.3[V]
3.1[V]
PLD IC8001 controls the output voltage with a serial communication between IC8001 and IC9001.
6. 3.0V Generator Circuit (3.0V Regulator Circuit)
When 3.3V voltage generated by IC9001 is input to pin-27 [LD2IN] and supplied to +3.0V Regulator circuit inside IC9001, 3.0V voltage is generated and output from pin-30
[LDO2OUT] to the unit.
[LDO2OUT] to the unit.
One Point:
In this unit, 1.10V is supplied to 3.0V line via D9004 until the 3.0V voltage is generated for the start-up of PLD IC8001.
7. 5.0V Generator Circuit (Step-up DC-DC CONVERTER -4)
7. 5.0V Generator Circuit (Step-up DC-DC CONVERTER -4)
When 3.0V voltage generated by IC9001 is input to pin-7 [DCOC4EN], the Step-up DC-DC CONVERTER Circuit-4 inside IC9001 starts up. This circuit is a step-up DC-DC
converter circuit consisting of L9001, D9003, C9019 and the step-up circuit inside IC9001. This circuit operates as follows. The step-up DC-DC converter circuit-4 controls
the dutyt ratio of the PWM waveform which is output from pin-5 [VO4], with monitoring the voltage input to pin-19 [FB4] of IC9001. By this operation, the step-up circuit
works, and the 5.0V voltage is generated and supplied to the unit.
converter circuit consisting of L9001, D9003, C9019 and the step-up circuit inside IC9001. This circuit operates as follows. The step-up DC-DC converter circuit-4 controls
the dutyt ratio of the PWM waveform which is output from pin-5 [VO4], with monitoring the voltage input to pin-19 [FB4] of IC9001. By this operation, the step-up circuit
works, and the 5.0V voltage is generated and supplied to the unit.
8. VSTBY voltage
IC9001 has the reference voltage circuit and generates BG1 (+2.8[V]), BG2 (+1.4[V]) and BG3 (+0.6[V]). When IC9001 is in the sleep mode, BG1 voltage is output from
pin-37 [VSTBY]. When IC9001 is in the wake-up mode, 3.0V voltage is output from pin-37 [VSTBY].
One Point:
In this unit, BG1 (+2.8[V]), BG2 (+1.4[V]) and BG3 (+0.6[V]) are generated in the sleep mode.
9. XRST3 signal
9. XRST3 signal
After IC9001 wakes up, 3.3V voltage is input to RESET-3 circuit inside IC9001. When 3.3V voltage is input to RESET-3 circuit, the pin-51 [XRST3] terminal of IC9001
becomes “Open” state after the capacitive delay (about 5.6 [ms]) of C9012 that is externally connected to pin-54 [CRST3]. Then 3.3 voltage is supplied as the master reset
signal, XRST, via the pull-up resistor, R6054. About the detail of Reset Circuit, refer to “2-5. Reset Circuit” on page 15.
becomes “Open” state after the capacitive delay (about 5.6 [ms]) of C9012 that is externally connected to pin-54 [CRST3]. Then 3.3 voltage is supplied as the master reset
signal, XRST, via the pull-up resistor, R6054. About the detail of Reset Circuit, refer to “2-5. Reset Circuit” on page 15.
IC9001 has three reset circuits, RESET-1, RESET-2 and RESET-3. But in this unit, both RESET-1 and RESET-2 are not used.
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