19-4111; Rev 0; 5/08
Dual, 2.2MHz, Automotive Buck or Boost
Converter with 80V Load-Dump Protection
MX5098A
General Description
Features
The MAX5098A is a dual-output, high-switching-frequen-
cy DC-DC converter with integrated n-channel switches
that can be used either in high-side or low-side configura-
tion. Each output can be configured either as a buck con-
verter 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 charge-
pump 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 tran-
sient to prevent damage to lower voltage components.
o Wide 4.5V to 5.5V or 5.2V to 19V Input Voltage
Range (with Up to 80V Load-Dump Protection)
o Dual-Output DC-DC Converter with Integrated
Power MOSFETs
o Each Output Configurable in Buck or Boost Mode
o Adjustable Outputs from 0.8V to 0.85V Buck
IN
Configuration) and from V to 28V (Boost
IN
Configuration)
o I
and I
of 2A and 1A (Respectively) in
OUT2
OUT1
Buck Configuration
o Switching Frequency Programmable from 200kHz
The DC-DC converters operate over a wide operating
voltage range from 4.5V to 19V. The MAX5098A oper-
ates 180° out-of-phase with an adjustable switching fre-
quency 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.
to 2.2MHz
o Synchronization Input (SYNC)
o Clock Output (CKO) for Four-Phase Master-Slave
Operation
o Individual Converter Enable Input and Power-
Good Output
This device utilizes voltage-mode control for stable oper-
ation and external compensation, thus the loop gain is
tailored to optimize component selection and transient
response. This device can be synchronized to an exter-
nal 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, indi-
vidual enable for each DC-DC regulator (EN1 and EN2),
open-drain power-good outputs (PGOOD1 and
PGOOD2), and a shutdown input (ON/OFF).
o Low-I (7µA) Standby Current (ON/OFF)
Q
o Internal Digital Soft-Start and Soft-Stop
o Short-Circuit Protection on Outputs and
Maximum Duty-Cycle Limit
o Overvoltage Protection on Outputs with Auto
Restart
o Thermal Shutdown
o Thermally Enhanced 32-Pin TQFN Package
Other features of the MAX5098A include overvoltage pro-
tection, 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.
Dissipates up to 2.7W at +70°C
Ordering Information
PART
TEMP RANGE
PIN-PACKAGE
Applications
Automotive AM/FM Radio Power Supply
MAX5098AATJ+
-40°C to +125°C
32 TQFN-EP*
+Denotes a lead-free package.
*EP = Exposed pad.
Automotive Instrument Cluster Display
Pin Configuration appears at end of data sheet
________________________________________________________________ Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.