MAX1523EUT+T Maxim Integrated Products, MAX1523EUT+T Datasheet - Page 11

• Manufacturer Part Number: MAX1523EUT+T
• Description: IC SIMPLE BOOST CNTRLR SOT23-6
• Manufacturer: Maxim Integrated Products
• Type: Step-Up (Boost), Flyback, Sepicr

Specifications of MAX1523EUT+T

• Internal Switch(s): No
• Synchronous Rectifier: No
• Number Of Outputs: 1
• Voltage - Output: 2.5 ~ 100 V
• Frequency - Switching: 1MHz
• Voltage - Input: 2.5 ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: SOT-23-6
• Power - Output: 696mW
• Output Voltage: 2.5 V to 100 V
• Output Current: 0.95 A
• Input Voltage: 2.5 V to 5.5 V
• Supply Current: 25 uA
• Mounting Style: SMD/SMT
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Current - Output: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

The MAX1522/MAX1523/MAX1524s’ high switching fre-
quency demands a high-speed rectifier. Schottky
diodes are recommended for most applications
because of their fast recovery time and low forward
voltage. Ensure that the diode’s current rating is ade-
quate to withstand the diode’s RMS current:
Also, the diode reverse breakdown voltage must
exceed V
Schottky diodes may not be practical because of this
voltage requirement. In these cases, use a high-speed
silicon rectifier with adequate reverse voltage. Another
consideration for high input voltages is reverse leakage
of the diode. This should be considered using the man-
ufacturer’s specification due to its direct influence on
system efficiency.
High switching frequencies and large peak currents
make PC board layout a very important part of design.
Good design minimizes excessive EMI on the feedback
OUT
I
DIODE RMS
. For high output voltages (50V or above),
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Layout Considerations
I
OUT
×
I
PEAK
Diode Selection
Simple SOT23 Boost Controllers
paths and voltage gradients in the ground plane, both
of which can result in instability or regulation errors.
Connect the inductor, input filter capacitor, and output
filter capacitor as close together as possible, and keep
their traces short, direct, and wide. Connect their
ground pins at a single common node in a star-ground
configuration. The external voltage-feedback network
should be very close to the FB pin, within 0.2in (5mm).
Keep noisy traces (such as the trace from the junction
of the inductor and MOSFET) away from the voltage-
feedback network; also keep them separate, using
grounded copper. The MAX1522/MAX1523/ MAX1524
evaluation kit manual shows an example PC board lay-
out and routing scheme.
If the output capacitor’s ESR is too low for proper regu-
lation, it can be increased artificially directly on the PC
board. For example, an additional 50mΩ of ESR added
to the output capacitor provides best regulation. The
resistivity of a 10mil trace using 1oz copper is about
50mΩ per inch. Therefore, a 10mil trace 1in long gener-
ates the required resistance.
Generating Resistance
with PC Board Traces
11