1.0A Step-Down Switching Regulator
TC2575
TC2575
1.0A Step-Down Switching Regulator
FEATURES
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3.3V, 5.0V, 12V, and Adjustable Output Versions
Adjustable Version Output Voltage Range of
1.23V to 37V
±
4% Max. Over Line and Load Conditions
Guaranteed 1.0 A Output Current
Wide Input Voltage Range; 4.75V to 40V
Requires Only 4 External Components
52kHz Fixed Frequency Internal Oscillator
TTL Shutdown Capability, Low Power Standby Mode
High Efficiency
Uses Readily Available Standard Inductors
Thermal Shutdown and Current Limit Protection
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.
APPLICATIONS
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Simple and High-Efficiency Step-Down
(Buck) Regulator
Efficient Pre–Regulator for Linear Regulators
On–Card Switching Regulators
Positive to Negative Converters (Buck–Boost)
Negative Step-Up Converters
Power Supply for Battery Chargers
GENERAL DESCRIPTION
PIN CONFIGURATIONS
5-Pin TO-220
ORDERING INFORMATION
Part
Number
TC2575-3.3VAT
TC2575-5.0VAT
TC2575-12.0VAT*
TC2575VAT**
Package
5-Pin TO-220
5-Pin TO-220
5-Pin TO-220
5-Pin TO-220
Temperature
Range
–40 to +125°C
–40 to +125°C
–40 to +125°C
–40 to +125°C
TC2575
Note: * Contact factory for availability
** ADJ = 1.23 To 37V.
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TC2575-1 3/13/00
TelCom Semiconductor reserves the right to make changes in the circuitry and specifications of its devices.
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OUTPUT
GND
FEEDBACK
ON/OFF
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IN
TELCOM [ TELCOM SEMICONDUCTOR, INC ]
