RT8205A RICHTEK [Richtek Technology Corporation], RT8205A Datasheet - Page 27

• Manufacturer Part Number: RT8205A
• Description: High Efficiency, Main Power Supply Controllers for Notebook Computers
• Manufacturer: RICHTEK [Richtek Technology Corporation]

Copyright
DS8205A/B/C-06 July 2012
Protection
Protection
Discharge
Power-UP VREGx < UVLO threshold
Shutdown EN = low
Shutdown
=> High
=> High
=> High
=> High
=> High
=> High
Standby
Thermal
Voltage
Voltage
“>1V”
“>1V”
“>1V”
“>1V”
“>1V”
“>1V”
Under
Low
Mode
RUN
Over
EN
(V)
©
2012 Richtek Technology Corporation. All rights reserved.
high without 60us)
(after ENTRIP2 is
EN = high, VOUT1 or VOUT2
enabled
Either output > 111% of the nominal
level.
Either output < 70% of the nominal
level after 3ms time-out expires and
output is enabled
Either SMPS output is still high in
either standby mode or shutdown
mode
ENTRIPx < startup threshold,
EN = high.
TJ > +150°C
ENTRIP1
High
High
High
High
Low
Low
(V)
X
Condition
High (after ENTRIP1
is high without 60us)
Table 2. Operation Mode Truth Table
ENTRIP2
Table 3. Power-Up Sequencing
High
High
High
Low
Low
(V)
X
Transitions to discharge mode after a VIN POR and after REF
becomes valid. VREG5, VREG3, and REF remain active.
Normal Operation.
LGATEx is forced high. VREG3, VREG5 active. Exited by VIN
POR or by toggling EN, ENT RIPx
Both UGATEx and LGATEx are forced low and enter discharge
mode. VREG3, VREG5 active. Exited by VIN POR or by
toggling EN, ENTRIPx
During discharge mode, there is one path to discharge the
outputs capacitor residual charge. That is output capacitor
discharge to GND through an internal switch.
VREG3, VREG5 active.
All circuitry off.
All circuitry off. Exit by VIN POR or by toggling EN, ENTRIPx.
powers up)
powers up)
powers up)
powers up)
powers up)
powers up)
(after REF
(after REF
(after REF
(after REF
(after REF
(after REF
VREG5
Off
On
On
On
On
On
On
is a registered trademark of Richtek Technology Corporation.
powers up)
powers up)
powers up)
powers up)
powers up)
powers up)
(after REF
(after REF
(after REF
(after REF
(after REF
(after REF
VREG3
Off
On
On
On
On
On
On
Comment
RT8205A/B/C
SMPS2 on)
SMPS1
(after
ON
Off
Off
Off
On
On
On
www.richtek.com
SMPS1 on)
SMPS2
(after
Off
Off
On
On
Off
On
On
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