ISL6569CRZ-T Intersil, ISL6569CRZ-T Datasheet - Page 7

• Manufacturer Part Number: ISL6569CRZ-T
• Description: IC CTRLR PWM BUCK 2PHASE 32-QFN
• Manufacturer: Intersil

Specifications of ISL6569CRZ-T

• Pwm Type: Controller
• Number Of Outputs: 1
• Frequency - Max: 2MHz
• Duty Cycle: 75%
• Voltage - Supply: 4.75 V ~ 5.25 V
• Buck: Yes
• Boost: No
• Flyback: No
• Inverting: No
• Doubler: No
• Divider: Yes
• Cuk: No
• Isolated: No
• Operating Temperature: 0°C ~ 70°C
• Package / Case: 32-VQFN Exposed Pad, 32-HVQFN, 32-SQFN, 32-DHVQFN
• Frequency-max: 2MHz
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

GND
Bias and reference ground for the IC.
OVP
Over-voltage protection pin. This pin is pulled to VCC and is
latched when an over-voltage condition is detected. Connect
this pin to the gate of an SCR or MOSFET tied across V
and ground. A fuse must be placed upstream to open the
input supply rail and prevent damage to the load device.
VID4, VID3, VID2, VID1, VID0
The state of these five inputs program the internal DAC,
which provides the reference voltage for output regulation.
Connect these pins to either open-drain or active pull-up
type outputs. Pulling these pins above 2.9V can cause a
reference offset inaccuracy.
OFS
Connecting a resistor between this pin and ground creates a
positive offset voltage which is added to the DAC voltage,
allowing easy implementation of load-line regulation. For no
offset, simply tie this pin to ground.
FB and COMP
The internal error amplifier inverting input and output
respectively. Connect the external R-C feedback
compensation network of the regulator to these pins.
IOUT
The current carried out of this pin is proportional to output
current and can be used to incorporate output voltage droop
and/or load sharing. The scale factor is set by the ratio of the
ISEN resistors and the lower MOSFET r
desired, connect this pin to FB. When not used for droop or
load sharing, simply leave this pin open.
VSEN, RGND, VDIFF
VSEN and RGND are the inputs to the differential remote-
sense amplifier. Connect these pins to the sense points of
the remote load. Connect an appropriately sized feedback
resistor, R
VCC
Supplies all the power necessary to operate the chip. The IC
starts to operate when the voltage on this pin exceeds the
rising POR threshold and shuts down when the voltage on
this pin drops below the falling POR threshold. Connect this
pin directly to a +5V supply or through a series 255Ω resistor
to a +12V supply.
FB
, between VDIFF and FB.
7
DS(ON)
. If droop is
IN
ISL6569
ISEN1, ISEN2
Current sense inputs. A resistor connected between these
pins and their respective phase nodes sets a current
proportional to the current in the lower MOSFET during it’s
conduction interval. This current is used as a reference for
channel balancing, load sharing, protection, and load-line
droop.
PWM1, PWM2
Pulse-width modulating outputs. Connect these pins to the
individual HIP660x driver PWM input pins. These logic
outputs command the driver IC(s) in switching the half-
bridge configuration of MOSFETs.
PGOOD
Power good is an open-drain logic output that changes to a
logic low when the voltage at VDIFF is 350mV below the VID
setting or above 2.2V.
FS/DIS
A dual function pin for setting the switching frequency and
disabling the controller. Place a resistor from this pin to
ground to set the switching frequency between 25kHz and
1MHz. Pulling this pin below 0.8V disables the controller.
EN
Threshold sensitive enable input of the controller. Transition
this pin above 1.23V (typical enable threshold) to initiate a
soft-start cycle. Pull this pin below 1.14V, taking into account
the enable hysteresis, to disable the controller once in
operation. Connect a resistor divider to this pin to set the
power-on voltage level for proper coordination with Intersil
MOSFET drivers. If this function is not required, simply tie
this pin to VCC.
Multi-Phase Control
Microprocessor load current profiles have increased to the
point where the multi-phase power conversion advantage is
pronounced. The technical challenges associated with
producing a single-phase converter which is both cost-
effective and thermally viable have forced a change to the
cost-saving approach of multi-phase. The ISL6569 controller
helps reduce the complexity of implementation by integrating
vital functions and requiring minimal output components.
The block diagram in Figure 1 provides a top level view of
multi-phase power conversion using the ISL6569 controller.
December 29, 2004
FN9085.7