TC2575 Datasheet, PDF (1/25 Pages) TelCom Semiconductor, Inc – 1.0A Step-Down Switching Regulator

1.0A Step-Down Switching Regulator
T_TC_C2₂5₅7₇5
1.0A Step-Down Switching Regulator
FEATURES
s 3.3V, 5.0V, 12V, and Adjustable Output Versions
s Adjustable Version Output Voltage Range of
1.23V to 37V ±4% Max. Over Line and Load Conditions
s Guaranteed 1.0 A Output Current
s Wide Input Voltage Range; 4.75V to 40V
s Requires Only 4 External Components
s 52kHz Fixed Frequency Internal Oscillator
s TTL Shutdown Capability, Low Power Standby Mode
s High Efficiency
s Uses Readily Available Standard Inductors
s Thermal Shutdown and Current Limit Protection
APPLICATIONS
s Simple and High-Efficiency Step-Down
(Buck) Regulator
s Efficient Pre–Regulator for Linear Regulators
s On–Card Switching Regulators
s Positive to Negative Converters (Buck–Boost)
s Negative Step-Up Converters
s Power Supply for Battery Chargers
GENERAL DESCRIPTION
PIN CONFIGURATIONS
The TC2575 series of regulators are monolithic inte-
grated circuits ideally suited for easy and convenient design
of a step–down switching regulator (buck converter). All
circuits of this series are capable of driving a 1.0A load with
excellent line and load regulation. These devices are avail-
able in fixed output voltages of 3.3V, 5.0V, 12V, and
an adjustable output version.
These regulators were designed to minimize the num-
ber of external components to simplify the power supply
design. Standard series of inductors optimized for use with
the TC2575 are offered by several different inductor manu-
facturers.
Since the TC2575 converter is a switch-mode power
supply, its efficiency is significantly higher in comparison
with popular three-terminal linear regulators, especially with
higher input voltages. In many cases, the power dissipated
is so low, that no heatsinking is required or its size can be
reduced dramatically.
The TC2575 features include a guaranteed ±4% toler-
ance on output voltage within specified input voltages and
output load conditions, and ±10% on the oscillator frequency
(±2% over 0°C to +125°C). External shutdown is included,
featuring 80µA (typical) standby current. The output switch
includes cycle-by-cycle current limiting, as well as thermal
shutdown for full protection under fault conditions.
5-Pin TO-220
TC2575
1 2 345
ORDERING INFORMATION
Part
Number
Package
TC2575-3.3VAT 5-Pin TO-220
TC2575-5.0VAT 5-Pin TO-220
TC2575-12.0VAT* 5-Pin TO-220
TC2575VAT**
5-Pin TO-220
Note: * Contact factory for availability
** ADJ = 1.23 To 37V.
Temperature
Range
–40 to +125°C
–40 to +125°C
–40 to +125°C
–40 to +125°C
TC2575-1 3/13/00 ^{TelCom Semiconductor reserves the right to make changes in the circuitry an}1^{d specifications of its devices.}