TS33002 Datasheet, PDF (7/12 Pages) List of Unclassifed Manufacturers – High Efficiency Synchronous 1A/2A DC/DC Buck Converter, 5Mhz

TS33001/2
Version 1.3
FUNCTIONAL DESCRIPTION
This voltage-mode Point of Load (POL) synchronous step-down power supply product can be used in the consumer, industrial,
and automotive market segments. It includes flexibility to be used for a wide range of output voltages and is optimized for high
efficiency power conversion with low R_DSON integrated synchronous switches. A 5MHz internal switching frequency facilitates
low cost LC filter combinations and improved transient response. Additionally, the fixed output version, with integrated Power
on Reset and Fault circuitry enables a minimal external component count to provide a complete power supply solution for a
variety of applications.
DETAILED PIN DESCRIPTION
Unregulated input, VCC
This terminal is the unregulated input voltage source for the IC. It is recommended that a 22uF bypass capacitor be placed
close as possible to the VCC pins for best performance. Since this is the main supply for the IC, good layout practices need to
be followed for this connection.
Feedback, FB
This is the voltage feedback input terminal for the adjustable version. For the fixed mode versions, this pin should be left
floating and not connected.
The connection on the PCB should be kept as short as possible from the feedback resistors, kept away from the VSW
connections or other switching/high frequency nodes, and should not be shared with any other connection. This should
minimize stray coupling, reduce noise injection, and minimize voltage shift cause by output load.
To choose the resistors for the adjustable version, use the following equation:
V_OUT = 0.6 (1 + R_TOP/R_BOT)
For stability, RTOP should be 270K Ohms to 330K Ohms.
Output Voltage Sense, V_OUT Sense
This is the input terminal for the voltage output feedback and is needed for both adjustable and fixed voltage versions. This
should be connected to the main output capacitor, and the same good layout practices should be followed as for the FB
connection. Keep this line as short as possible, keep it away from the VSW and other switching or high frequency traces,
and do not share this connection with any other connection on the PCB.
Switching output, VSW
This is the switching node of the regulator. It should be connected directly to the 0.47uH inductor with a wide, short trace.
It is switching between VCC and PGND at the switching frequency.
Ground, GND
This ground is used for the majority of the device including the analog reference, control loop, and other circuits.
Power Ground, PGND
This is a separate ground connection used for the low side synchronous FET to isolate switching noise from the rest of the
device.
Enable, EN
This is an input terminal to activate the entire device. This will enable the internal reference, oscillator, TSD, etc, and allow
the fault detection circuitry to work correctly. Notice that the EN needs to low for the part to exhibit 5uA quiescent current.
The input threshold is TTL/CMOS compatible and has a 4 Megaohm internal pull-up to ensure a stable state if the pin is
disconnected.
Specifications subject to change
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