SC2608B Datasheet, PDF (1/11 Pages) Semtech Corporation – Simple, Synchronous Voltage Mode PWM Controller

POWER MANAGEMENT
D_Dr_ea_sf_ct_ription
The SC2608B is a versatile voltage-mode PWM control-
ler designed for use in step down DC/DC power supply
applications. A simple, fixed frequency, highly efficient
buck regulator can be implemented using the SC2608B
with minimal external components. The input voltage
range is from +5V to +12V. Internal level shift and drive
circuitry eliminates the need for an expensive P-channel,
high-side MOSFET. The small device footprint allows for
compact circuit design.
SC2608B features include temperature compensated
voltage reference, triangle wave oscillator, current limit
comparator, and an externally compensated error ampli-
fier. Current limit is implemented by sensing the voltage
drop across the bottom MOSFET R_DS(ON).
The SC2608B operates at a fixed frequency of 250kHz
providing an optimum compromise between efficiency ,
external component size, and cost.
SC2608B has a thermal protection circuit, which is
activated if the junction temperature exceeds 150 ^OC.
SC2608B
Simple, Synchronous
Voltage Mode PWM Controller
Features
‹ +5V or +12V input voltage
‹ 250kHz operation
‹ High efficiency (>90%)
‹ 1.25% Voltage feedback accuracy over tempera-
ture
‹ Hiccup mode over current protection
‹ 1.2A output drive
‹ R Current sensing for protection
DS(ON)
‹ Industrial temperature range
‹ Available in SO-8 package
‹ Integrated boot strap diode
‹ Thermal Shut down
‹ Fully WEEE and RoHS Compliant
Applications
‹ Termination supplies
‹ Low cost microprocessor supplies
‹ Peripheral card supplies
‹ Industrial power supplies
‹ High density DC/DC conversion
Typical Application Circuit
Revision 4: Jan. 2007
Figure 1
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