Datasheet
MAX17497A/MAX17497B
AC-DC and DC-DC Peak Current-Mode Converters
with Integrated Step-Down Regulator
29Maxim Integrated
Layout, Grounding, and Bypassing
All connections carrying pulsed currents must be very
short and as wide as possible. The inductance of these
connections must be kept to an absolute minimum due
to the high di/dt of the currents in high-frequency switch-
ing power converters. This implies that the loop areas for
forward and return pulsed currents in various parts of the
circuit should be minimized. Additionally, small-current
loop areas reduce radiated EMI. Similarly, the heatsink
of the main MOSFET presents a dV/dt source; therefore,
the surface area of the MOSFET heatsink should be mini-
mized as much as possible.
Ground planes must be kept as intact as possible. The
ground plane for the power section of the converter
should be kept separate from the analog ground plane,
except for a connection at the least noisy section of the
power ground plane, typically the return of the input filter
capacitor. The negative terminal of the filter capacitor,
the ground return of the power switch, and the current-
sensing resistor must be close together. PCB layout also
affects the thermal performance of the design. A number
of thermal vias that connect to a large ground plane
should be provided under the exposed pad of the part for
efficient heat dissipation. For a sample layout that ensures
first-pass success, refer to the MAX17497A evaluation kit
layout available at www.maximintegrated.com.
For universal AC input designs, follow all applicable
safety regulations. Offline power supplies can require UL,
VDE, and other similar agency approvals.
Ordering Information
Package Information
For the latest package outline information and land patterns (footprints), go to www.maximintegrated.com/packages. Note that a
“+”, “#”, or “-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the
drawing pertains to the package regardless of RoHS status.
+Denotes a lead(Pb)-free/RoHS-compliant package.
PART TEMP RANGE PIN-PACKAGE DESCRIPTION
MAX17497AATE+
-40NC to +125NC
16 TQFN
250kHz, Offline Flyback Converter with 3.3V, 600mA
Synchronous Step-Down Converter
MAX17497BATE+
-40NC to +125NC
16 TQFN
500kHz, Flyback/Boost Converter with 3.3V, 600mA
Synchronous Step-Down Converter
PACKAGE TYPE PACKAGE CODE OUTLINE NO. LAND PATTERN NO.
16 TQFN T1633+5
21-0136 90-0032