Doc No. TA4-EA-A0521
VIN = 5 to 39 V, 1-channel DC-DC Step down Regulator
integrated N-channel Power MOSFET
Current Feedback Function compensates output voltage
AN33017UA is 1-channel DC-DC Step down Regulator
drop due to external USB cable loss
integrated N-channel Power MOSFET and employs the
Internal reference voltage is within 1% accuracy.
voltage mode switching control system.
Input Voltage Range : PVCC , VCC: 5 V to 39 V
Switching frequency is adjustable within the range of 200
kHz to 2 MHz by an external resistor.
Standby mode consumes less than 1µA current.
Adjustable Output Voltage Range with external Resistor :
1.2 V ~ 9 V.
Output over voltage protection (OVP1) function.
Output ground short protection function.
Input over voltage protection (OVP2) function.
This IC can be operated with wide input voltage range
and is build in several protection functions, so this IC can
provide high reliability power supply system.
Since it is possible to use up to 2MHz switching
frequency and it is unnecessary to add external parts for
High Side Switch, this IC realizes downsizing of set and
reducing in the number of external parts.
For USB applications, this IC can controlled USB
supplied voltage level with external resistor for USB load
current monitor (Current Feedback Function), and it can
Over current protection (OCP) with adjustable threshold.
Over current detection level with switchable.
Power supply under-voltage lockout (UVLO) function.
Thermal Shut-Down (TSD) function.
Adjustable soft-start function.
48 pin Plastic Quad Flat Package With Heat Sink.
provide suitable power supply system for external USB
with no voltage drop due to USB cable loss.
Maximum current is 2.1 A.
High Input Voltage Power Systems for USB such as
・Home Appliances etc.
5 V ~ 39 V
EN VREG VCC
TL AN33017UA IN_HIGH
RTCTSGND SS FB
0.1 7.5k 2.2nF
300 600 900 1200 1500
This application circuit is an example. The operation of mass production set
VIN = 6 V, 12 V, 39 V
is not guaranteed. You should perform enough evaluation and verification
on the design of mass production set. You are fully responsible
for the incorporation of the above application circuit and information
VOUT = 5 V, LO = 10 µH, CO = 22 µF
Frequency = 490 kHz
in the design of your equipment.
This block diagram is for explaining functions. The part of the block diagram
may be omitted, or it may be simplified.
These components should be put without fail for reducing the ringing of
LX1~5 in light load condition. Please use snubber resistance over 0.5W.
Please refer to “OPERATION13.Snubber circuit value setting” for setting specific value.
Load resistance, Rload should be put without fail. Load resistance
under 330Ωis recommended in VOUT=5V condition. Please refer to
“OPERATION14.Load resistance, Rload setting” for setting specific value.
SS pin capacitor, CSS and TL pin capacitor CTL should be put 0.1uF.
If you change these components, please keep “ CTL > CSS × 0.9 “ relation.
Established : 2017-06-28
Revised : ####-##-##
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