The MAX5098A is a dual-output, high-switching-frequency
DC-DC converter with integrated n-channel switches
that can be used either in high-side or low-side configuration.
Each output can be configured either as a buck converter
or a boost converter. In the buck configuration, this
device delivers up to 2A from converter 1 and 1A from
converter 2. The MAX5098A also integrates a load-dump
protection circuitry that is capable of handling load-dump
transients up to 80V for automotive applications. The
load-dump protection circuit utilizes an internal chargepump
to drive the gate of an external n-channel MOSFET.
When an overvoltage or load-dump condition occurs, the
series protection MOSFET absorbs the high voltage transient
to prevent damage to lower voltage components.
The DC-DC converters operate over a wide operating
voltage range from 4.5V to 19V. The MAX5098A operates
180° out-of-phase with an adjustable switching frequency
to minimize external components while allowing
the ability to make trade-offs between the size, efficiency,
and cost. The high switching frequency (up to 2.2MHz)
also allows this device to operate outside the AM band
for automotive applications.
This device utilizes voltage-mode control for stable operation
and external compensation, thus the loop gain is
tailored to optimize component selection and transient
response. This device can be synchronized to an external
clock fed at the SYNC input. Also, a clock output
(CKO) allows a master-slave connection of two devices
with a four-phase synchronized switching sequence.
Additional features include internal digital soft-start, individual
enable for each DC-DC regulator (EN1 and EN2),
open-drain power-good outputs (PGOOD1 and
PGOOD2), and a shutdown input (ON/OFF).
Other features of the MAX5098A include overvoltage protection,
short-circuit (hiccup current limit) and thermal
protection. The MAX5098A is available in a thermally
enhanced, exposed pad, 5mm x 5mm, 32-pin TQFN
package and is fully specified over the automotive
-40°C to +125°C temperature range.
Applications
Automotive AM/FM Radio Power Supply
Automotive Instrument Cluster Display