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TMI and SUNTO are the brands of TOLL microelectronic inc.
STI3474 V0.7 2018.11
www.toll-semi.com www.suntosemi.com
STI3474
600kHz, 18V, 3A Synchronous Step-Down Converter
FEATURES
⚫ 600kHz Frequency Operation
⚫ 3.0A Output Current
⚫ No Schottky Diode Required
⚫ 3.5V to 18V Input Voltage Range
⚫ 0.8V Reference
⚫ Slope Compensated Current Mode Control for
Excellent Line and Load Transient Response
⚫ Integrated internal compensation
⚫ Stable with Low ESR Ceramic Output Capacitors
⚫ Over Current Protection with Hiccup-Mode
⚫ Input overvoltage protection (OVP)
⚫ Thermal Shutdown
⚫ Inrush Current Limit and Soft Start
⚫ Available in SOT23-6 Package
GENERAL DESCRIPTION
The STI3474 is a fully integrated, high efficiency
3.0A synchronous rectified step-down converter.
The STI3474 operates at high efficiency over a
wide output current load range.
This device offers two operation modes, PWM
control and PFM Mode switching control, which
allows a high efficiency over the wider range of
the load.
The STI3474 requires a minimum number of
readily available standard external components
and is available in a 6-pin SOT23-6 ROHS compliant
package.
APPLICATIONS
⚫ Vehicle USB Power Chargers
⚫ Distributed Power Systems
⚫ Digital Set Top Boxes
⚫ Flat Panel Television and Monitors
⚫ Notebook computer
⚫ Wireless and DSL Modems
TYPICAL APPILCATION
Figure 1. Basic Application Circuit
Note: if RT=0Ω, R1 should be 56kΩ~200kΩ
Efficiency
V
OUT
=3.3V, I
OUT
=0.01A to 2.5A, L
OUT
=4.7μH, T
A
=25°C
40%
50%
60%
70%
80%
90%
100%
0.01 0.1 1 10
Efficiency
Output Current (A)
Vin=8V
Vin=12V
Vin=16V