MAX17061AEVKIT+ Maxim Integrated Products, MAX17061AEVKIT+ Datasheet - Page 23

• Manufacturer Part Number: MAX17061AEVKIT+
• Description: Power Management Modules & Development Tools MAX17061A EVAL KIT MAX17061A EVAL KIT
• Manufacturer: Maxim Integrated Products

Specifications of MAX17061AEVKIT+

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

The current through each FB_ pin is controlled only
during the step-up converter’s on-time. During the con-
verter’s off-time, the current sources are turned off. The
output voltage does not discharge and stays high. The
MAX17061A disables the FB current source to which
the string is shorted. In this case, the step-up convert-
er’s output voltage is always applied to the disabled FB
pin. The FB_ pin can withstand 45V.
Careful PCB layout is important for proper operation.
Use the following guidelines for good PCB layout:
1) Minimize the area of high current switching loop of
2) Connect high-current input and output components
rectifier diode, internal MOSFET, and output capac-
itor to avoid excessive switching noise.
with short and wide connections. The high-current
input loop goes from the positive terminal of the input
capacitor to the inductor, to the internal MOSFET,
then to the input capacitor’s negative terminal. The
high-current output loop is from the positive termi-
nal of the input capacitor to the inductor, to the rec-
tifier diode, to the positive terminal of the output
capacitors, reconnecting between the output
capacitor and input capacitor ground terminals.
Avoid using vias in the high-current paths. If vias
are unavoidable, use multiple vias in parallel to
reduce resistance and inductance.
______________________________________________________________________________________
FB Pin Maximum Voltage
PCB Layout Guidelines
SMBus for LCD Panel Applications
8-String White LED Driver with
3) Create a ground island (PGND) consisting of the
4) Place the overvoltage detection divider resistors as
5) Place IN pin bypass capacitor as close as possible
6) Minimize the size of the LX node while keeping it
Refer to the MAX17061A evaluation kit for an example
of proper board layout.
input and output capacitor ground and negative ter-
minal of the current-sense resistor. Connect all
these together with short, wide traces or a small
ground plane. Maximizing the width of the power-
ground traces improves efficiency and reduces out-
put-voltage ripple and noise spikes. Create an
analog ground island (AGND) consisting of the
overvoltage detection divider ground connection,
the ISET and FSET resistor connections, CCV
capacitor connections, and the device’s exposed
backside pad. Connect the AGND and PGND
islands by connecting the GND pins directly to the
exposed backside pad. Make no other connections
between these separate ground planes.
close as possible to the OV pin. The divider’s cen-
ter trace should be kept short. Placing the resistors
far away causes the sensing trace to become
antennas that can pick up switching noise. Avoid
running the sensing traces near LX.
to the device. The ground connection of the IN
bypass capacitor should be connected directly to
GND pins with a wide trace.
wide and short. Keep the LX node away from the
feedback node and ground. If possible, avoid run-
ning the LX node from one side of the PCB to the
other. Use DC traces as shield if necessary.
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