iru3072 International Rectifier Corp., iru3072 Datasheet - Page 4

• Manufacturer Part Number: iru3072
• Description: 20-pin Synchronous Pwm Controller/ 3 Ldo Controller -
• Manufacturer: International Rectifier Corp.

IRU3072
PIN#
4
10
11
12
13
14
15
16
17
18
19
20
PIN SYMBOL
V
SEN33
OCSet
Comp
SS
SS1
Fb1
Fb2
Fb3
Fb4
Vc
Rt
LDO
/SDB
This pin is connected to a voltage that must be at least 4V higher than the bus voltage of
the switcher (assuming 5V threshold MOSFET) and powers the high side output driver. A
minimum of 1mF, high frequency capacitor must be connected from this pin to ground to
provide peak drive current capability.
This pin is connected to the Drain of the synchronous MOSFET and it provides the posi-
tive sensing for the internal current sensing circuitry. An external resistor programs the
current sense (CS) threshold depending on the R
This pin is used to monitor the 3.3V rail. This pin can be pulled-low to shutdown the
outputs.
This pin sets the switching frequency with a resistor to Gnd.
This pin is connected directly to the output of the switching regulator via resistor divider to
provide feedback to the Error amplifier.
Compensation pin of the error amplifier. An external resistor and capacitor network is
typically connected from this pin to ground to provide loop compensation.
This pin provides soft-start for the switching regulator. An internal current source charges
an external capacitor that is connected from this pin to ground which ramps up the output
of the switching regulator, preventing it from overshooting as well as limiting the input
current.
This pin provides soft-start for the LDO controllers. An internal current source charges an
external capacitor that is connected from this pin to ground which ramps up the output of
the LDO controller, preventing it from overshooting as well as limiting the input current.
These pins provide feedback for the linear regulator controllers.
PIN DESCRIPTION
www.irf.com
DS
of the power MOSFET.
Rev. 1.0
3/25/04