IR3623MPBF_1 IRF [International Rectifier], IR3623MPBF_1 Datasheet - Page 13

• Manufacturer Part Number: IR3623MPBF_1
• Description: HIGH FREQUENCY 2-PHASE, SINGLE OR DUAL OUTPUT SYNCHRONOUS STEP DOWN CONTROLLER WITH OUTPUT TRACKING AND SEQUENCING
• Manufacturer: IRF [International Rectifier]

Output
Sequencing
The IR3623 can accommodate a full spectrum of
user programmable tracking and sequencing
options using Track, Seq, Enable and Power
Good pins.
Through these pins both simple voltage tracking
such as that required by the DDR memory
application or more sophisticated sequencing
such ratiometric or simultaneously can be
implemented.
The Seq pin controls the internal current sources
to set the power up or down sequencing, toggle
this pin high for power up and toggle this pin low
for power down.
The Track pin is used to determine the second
channel
simultaneously by using two external resistors.
Figure 9 shows how these pins are configured for
different sequencing mode.
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V
o1
R
R
A
B
V
o1
C
SS1/SD1
SS1
R
R
R
D
Fig. 9: Sequencing using Track pin
E
R
Floating
C
output
V
F
VP1
V
Seq
Fb1
REF
SS2/SD2
o2
Voltage
Floating
Fb2
64uA
POR
VP2
Track2
for
POR
64uA
either
Tracking
E/A1
3V
ratiometric
I
SS1 = 28uA
E/A2
3V
I
SS2 = 28uA
I
hiccup2 = 3uA
I
hiccup1 = 3uA
and
OCP2
or
OCP1
In general the R
for the first output and R
voltage for the second output.
For simultaneously vs. ratiometric, RE and RF
can be selected according to the table below:
The Track pin must be connected to Vout3 if it is
not used. For current share mode, high output
voltage application (e.g. 5V) this pin needs to be
connected to Vcc.
Track Pin
Fig. 10: Ratiometric Power up /down
Fig. 11: Simultaneously Power Up / down
R
R
E
F
simultaneously
A
and R
R
R
C
D
B
C
IR3623MPbF
set the output voltage
and R
D
ratiometric
set the output
R
R
A
B
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