IP1206TRPBF International Rectifier, IP1206TRPBF Datasheet - Page 16

• Manufacturer Part Number: IP1206TRPBF
• Description: IC PWR BLOCK MULTIPHASE 30A LGA
• Manufacturer: International Rectifier
• Series: iPOWIR™r
• Type: Step-Down (Buck), PWM - Voltage Moder

Specifications of IP1206TRPBF

• Internal Switch(s): Yes
• Synchronous Rectifier: Yes
• Number Of Outputs: 1 or 2
• Voltage - Output: 0.8 V ~ 5.5 V
• Current - Output: 30A, 15A
• Frequency - Switching: 200kHz ~ 600kHz
• Voltage - Input: 7.5 V ~ 14.5 V
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: *
• Package / Case: *
• Package: LGA - 15.5 x 9.25
• Circuit: Single Output or Dual Ch
• Iout (a): 30
• Switch Freq (khz): 200 - 600
• Input Range (v): 7.5 - 14.5
• Output Range (v): 0.8 - 5.5
• Ocp Otp Uvlo Pre-bias Soft Start And: Pre-Bias + SEQ + SYNC + Tracking
• Pbf: PbF Option Available
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

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Over-Current Protection
The over current protection is performed by
sensing current through the R
MOSFET. This method enhances the converter’s
efficiency and reduce cost by eliminating a
current sense resistor. As shown in Fig. 16, an
external resistor (R
OCSet pin and the drain of low side MOSFET
(Q2) which sets the current limit set point.
When the overcurrent trip threshold is reached,
the power supply output shuts down and
attempts to restart, entering into the hiccup
mode. The time duration between the shutdown
of the output and the restart is determined by the
time it takes to discharge the soft start capacitor.
The duty cycle of the hiccup process is typically
5%. The hiccup is performed by charging and
discharging the soft-start capacitor at a certain
slope rate. As shown in Fig. 17 a 3µA current
source is used to discharge the soft-star t
capacitor. The OCP comparator resets after
every soft start cycle, the converter stays in this
mode until the overload or short circuit is
removed. Once the condition is removed the
converter will automatically recover.
Fig. 24 for R
Fig. 16: Connection of over current sensing resistor
Fig. 17: 3uA current source for discharging
Hiccup
Control
soft-start capacitor during hiccup
iP1206
SS1 / SD
OCSET
I
OCSET
22uA
selection.
20
OCSET
28uA
) is connected between
3uA
Q1
Q2
DS(on)
OCP
V
OC1
PGND
SW
of low side
R
OCSET
Refer to
L1
2/26/2008
V
OUT
(Output Voltage before startup)
Pre-Bias
iP1206 is able to start up into a pre-charged
output,
disturbances of the output voltage.
The output starts in asynchronous fashion and
keeps the synchronous MOSFET off until the first
gate signal for control MOSFET is generated.
The figure below shows a typical Pre-Bias
condition at start up.
Depending on the system configuration, specific
amount of output capacitors may be required to
prevent discharging the output voltage.
Over Voltage Protection
Over-voltage is sensed through two dedicated
sense pins FBS1, FBS2. A separate OVP circuit
is provided for each channel.
The OVP threshold is user programmable and
can be set by two external resistors. Upon over-
voltage condition of either one of the outputs, the
OVP forces a latched shutdown on the fault
output and pulls low the low side driver.
Reset is performed by recycling the Vcc or
Enable. Overvoltage can be sensed either by
connecting
corresponding outputs through separate output
voltage divider resistor networks, or they can be
connected
feedback pins FB1 and FB2. For Type III
compensation, FB1s and FB2s should be
connected through voltage dividers only.
Power Good
The iP1206 provides two separate open collector
power good signals which report the status of the
outputs. The outputs are sensed through the two
dedicated V
Once the iP1206 is enabled and the outputs
reach the set value (90% of set value) the power
good signals go open and stay open as long as
the outputs stay within the set values.These pins
are open collector and need to be externally
pulled high.
Pre-Bias Voltage
Volt
which
SEN1
directly
FB1s
and V
prevents
SEN2
to
and
iP1206PbF
pins.
their
FB2s
oscillation
corresponding
Time
to
Vo
their
and
16