LTC3589HUJ#PBF Linear Technology, LTC3589HUJ#PBF Datasheet - Page 29

• Manufacturer Part Number: LTC3589HUJ#PBF
• Description: IC DC/DC CONV 8-OUTPUT 40QFN
• Manufacturer: Linear Technology

Specifications of LTC3589HUJ#PBF

• Applications: Handheld/Mobile Devices
• Current - Supply: 8µA
• Voltage - Supply: 2.7 V ~ 5.5 V
• Operating Temperature: -40°C ~ 150°C
• Mounting Type: Surface Mount
• Package / Case: *
• Primary Input Voltage: 5.5V
• No. Of Outputs: 8
• Output Voltage: 5V
• Output Current: 1.6A
• No. Of Pins: 40
• Operating Temperature Range: -40°C To +150°C
• Msl: MSL 1 - Unlimited
• No. Of Ldo Regulators: 3
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

OPERATION
seconds, and 3) a fault condition is detected. Fault condi-
tions are low V
undervoltage of one of the regulator outputs. All regulator
enables, the ON input, and PWR_ON signals are inhibited
for one second while in the PDN state. After one second
in PDN the pushbutton controller returns to POFF .
PBSTAT Operation
PBSTAT goes LOW 50ms after the initial pushbutton ap-
plication (ON LOW) and will stay LOW for a minimum of
50ms. PBSTAT will go HIGH coincident with ON going HIGH
unless ON goes HIGH before the 50ms minimum on-time.
Power-Up Using the Pushbutton
When in the POFF state, the LTC3589/LTC3589-1 is in
complete shutdown except the always active LDO1 and
regulators enabled with the keep-alive control bits. Pull the
ON pin to ground with a pushbutton for 400ms to begin a
power-up sequence with the WAKE pin tied to an enable
pin. Drive PWR_ON high within five seconds to signal
the LTC3589/LTC3589-1 to remain in the power-on state.
Power-Down Using the Pushbutton
The pushbutton power-down operation is performed by
the system microprocessor by monitoring the PBSTAT pin.
Once in the PON state, the system controller is responsible
for deciding what action to take with a pushbutton event.
When the ON pin is held LOW for a 50ms debounce period,
the PBSTAT pin is pulled LOW. The system controller should
monitor the PBSTAT pin to determine the pushbutton has
been pushed. If the controller decides that a power-down
is desired, then it should drive the PWR_ON pin LOW.
PB400ms OR
PWR_ON
POFF
1 SEC
POR
Figure 5. Pushbutton Controller State Diagram
LTC3589
PUP
PDN
IN
5 SEC
, device over temperature, or extended
FAULT OR
PWR_ON
PON
POR
PB400ms OR
PWR_ON
POFF
1 SEC
LTC3589-1
PUP
PDN
3589 F05
5 SEC
FAULT OR
PWR_ON
PON
Power-Up and Down Using PWR_ON Pin
An alternate power-up method is to drive the PWR_ON pin
to a HIGH state. After a delay of 50ms from the PWR_ON
signal, the WAKE pin will pull HIGH to drive regulator en-
able pins. When PWR_ON is HIGH for five seconds, the
sequence controller will enter the PON state. To power
down, drive the PWR_ON pin LOW. 50ms later WAKE will
pull low, all enabled regulators are disabled and the OVEN
command register is reset to 0x00.
Hard Reset Using the Pushbutton
When the ON pin is pulled LOW for five seconds, a hard
reset is initiated. At the end of five seconds, WAKE is pulled
LOW, the I
enable pin states are ignored, and the one second power-
down timer is started. During the power-down time, the
enables continue to be ignored to allow the regulator outputs
to discharge. The RSTO pin is pulled LOW for the power-
down time to indicate a pushbutton hard reset occurred.
If the PWR_ON pin is LOW at the end of the one second
power-down time, the LTC3589/LTC3589-1 will remain in
sleep mode. If PWR_ON is HIGH at the end of one second
and there are no fault conditions, the LTC3589/LTC3589-1
will power-up in the same way shown in Figure 8.
Hard Reset Due to a Fault Condition
A hard reset due to V
age of an output rail, or an overtemperature condition
initiates a hard shutdown of the LTC3589/LTC3589-1. When
the fault occurs, wake is pulled LOW, the I
registers are reset to POR states, enable pin inputs are
ignored, and the one second power-down timer is started.
During the power-down time, the enables continue to be
ignored to allow the regulator outputs to discharge. If the
PWR_ON pin is LOW at the end of the power-down time,
the LTC3589/LTC3589-1 will remain in sleep mode with just
the always-active LDO operating. If PWR_ON is HIGH at
the end of one second and the fault condition has cleared,
the LTC3589/LTC3589-1 will power-up in the same way
shown in Figure 8. Neither IRQ nor the status registers
are cleared by the fault induced shutdown.
2
C command registers are reset to POR states,
LTC3589/LTC3589-1
IN
undervoltage, extended undervolt-
2
C command
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