16 | ELMOS Product catalog 10/2004

adjustable, wide input range

910.24/25/26

pfm controller

DC/DC Converter

features

• Supply voltage range VS 3.0V to 60V

• Up to 90% efficiency

• 40µA standby current

• 180µA circuit operating current

• 1.5V to 24V or more adjustable output voltage

• Up to 300kHz switching frequency

• Improved current-limited PFM control scheme

• High current driver for external MOSFET

• Under-voltage lockout and thermal shutdown

• -40°C to 125°C operating temperature

• SO8 package

• 910.26 basis version

• 910.24 additive with peak current halving for

medium loads and extended max. switch-on-time

• 910.25 additive with peak current halving for

medium loads and extended max. switch-on-time

and fault protection

applications

• Minimum component DC-DC converters

• 14V, 28V or 42V automotive systems

• Power conditioning for portable equipment

• High efficiency on-card switching regulators

description

The family of highly flexible, easy to use PFM controllers is ideal for

the use in wide input range switching regulator applications.

An advanced PFM control scheme gives these devices the benefits of

PWM converters with high efficiency for heavy loads, while using very

low operating current for light loads to maintain excellent behaviour

with output load variation.

The switching circuits are suitable for topologies requiring low side

FET, such as boost, flyback, Sepic, etc. Depending on the utilized

topology the controllers are capable of producing regulated positive

or negative output voltage.

Operating from 3V to 60V supply and in temperature ranges from

-40°C to 125°C the device is well suited for automotive applications.

Requiring a minimum number of external components, these regula-

tors are simple to use and cost-saving.

Self-protection features include an overload detection circuit, an

overtemperature shutdown under fault conditions and an under-volt-

age lockout.

block diagram

VBAT

VS

PFM

Circuit

int. Supply &

References

On/Off

Logic

Gain

Control (1)

Overload

Protection (2)

VSM

ON

VSM

PGND

Instr.

Ampl.

+

-

VFB

AGND

ISEN

MDRV

VOut

DRV