MAX15003EVKIT+ Maxim Integrated Products, MAX15003EVKIT+ Datasheet - Page 5

• Manufacturer Part Number: MAX15003EVKIT+
• Description: Power Management Modules & Development Tools KIT EVAL FOR MAX15003
• Manufacturer: Maxim Integrated Products

Specifications of MAX15003EVKIT+

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

The MAX15003 IC can be programmed to power up
and power down the three outputs in sequence, ratio-
metric tracking, or coincident tracking mode by config-
uring the SEL pin. The MAX15003 EV kit features jumper
JU1 to configure the SEL pin. See Table 2 for jumper
JU1 configuration. The EV kit circuit is configured for
ratiometric tracking operation by default (resistors R3
and R27 shorted with PC trace), and can be easily mod-
ified for sequencing or coincident tracking. In ratiomet-
ric tracking mode, the soft-start controllers for VOUT1,
VOUT2, and VOUT3 are synchonized, and hence their
respective output voltages will track ratiometrically.
In concident tracking mode, the VOUT2 and VOUT3
output voltages ramp up, tracking the VOUT1 voltage
depending on the resistor-divider ratio used for R2/R3
and R26/R27, respectively.
In sequencing mode, VOUT2 and VOUT3 outputs do
not turn on until the voltage at the IC EN/TRACK_ input
pin for each output reaches 1.22V. The ratio of resistor
pairs R2/R3 and R26/R27 set the voltage threshold that
VOUT1 must reach before VOUT2 and VOUT3 are
turned on.
For sequencing or concident tracking operation, the EV
kit PCB requires modification. Cut open the shorting PCB
trace at resistors R3 and R27 and install resistors R2, R3,
R26, and R27. Refer to the Coincident/Ratiometric
Tracking (SEL, EN/TRACK_) and the Output-Voltage
Sequencing (SEL, EN/TRACK_, PGOOD) sections in the
MAX15003 IC data sheet to calculate the proper values
for resistors R2, R3, R26, and R27.
Table 2. Track/Sequence Operation (Jumper JU1)
* Default position.
SHUNT POSITION
1-2*
2-3
_______________________________________________________________________________________
Output Sequencing/Tracking
SEL PIN CONNECTION
Connected to SGND
Connected to REG
Ratiometric tracking
Coincident tracking
Sequence mode
EV KIT VOUT_
OPERATION
mode*
mode
MAX15003 Evaluation Kit
The three DC-DC converters can switch in phase or at
120° out-of-phase. Operating the converters in the out-
of-phase mode increases the input capacitor ripple fre-
quency, reduces the RMS input ripple current, and thus
the size of the input bypass capacitor requirement. EV
kit jumper JU2 is used to configure the phase mode
operation. See Table 3 for jumper JU2 configuration.
The MAX15003 EV kit provides PGOOD1, PGOOD2,
and PGOOD3 logic output signals to indicate the regu-
lation state of VOUT1, VOUT2, and VOUT3. A logic-low
at the PGOOD_ pads indicates that output voltage has
dropped below 92.5% of its regulation voltage. Each
PGOOD_ signal is pulled high to the respective VOUT_
voltage when in regulation. The EV kit also provides a
RESET logic output signal that indicates when all three
PGOOD outputs are logic-high. The RESET output is
pulled high (5V) after all three PGOOD signals are
pulled high and a timeout period of 22ms has elapsed.
Use the following equation to calculate the new capaci-
tor value for C22 to modify the timeout period:
Table 3. Phase Mode (Jumper JU2)
* Default position.
POSITION
SHUNT
2-3*
1-2
Calculate values for resistors R2, R3, R26, and R27
Connected to SGND
Connected to REG
CONNECTION
EV KIT CIRCUIT MODIFICATIONS
PHASE PIN
C
22
Short/0Ω resistors (R3, R27)
Open resistors (R2, R26)
=
2
μ
A T
Status Output Signals
×
2
TIMEOUT
V
120° out-of-phase mode
Phase Operation
EV KIT OPERATION
In-phase mode
5