RT7232GQW Datasheet, PDF (5/12 Pages) Richtek Technology Corporation – Evaluation Board

RT7232GQW
Evaluation Board
Test Points
The EVB is provided with the test points and pin names listed in the table below.
Test point/
Pin name
VIN
VOUT
GND
SW
EN
JP1
BOOT
SS
PVCC
PG
Signal
Input voltage
Output voltage
Ground
Switching node test point
Enable test point
Chip enable control
Boot strap supply test point
Soft-start control test point
Linear regulator output test
point
Power good output test
point
Comment (expected waveforms or voltage levels on test points)
Input voltage range = 4.5V to 18V
Default output voltage = 1.05V
Output voltage range = 0.765V to 8V
(see ‘’ Output Voltage Setting’’ section for changing output voltage level)
Ground reference for the input voltage, output voltage and analog ground
SW waveform
Enable signal. Drive EN or install a shorting block on Jumper JP1 to
enable operation (shorting 2-3) or disable operation (shorting 1-2).
Install jumper or drive EN directly to enable or disable operation
Floating supply voltage for the high-side N-MOSFET switch
Soft start waveform
Internal linear regulator output= 5.1V
Connected to PVCC through R29, PG voltage is 5.1V when soft-start is
complete and the output voltage is in regulation
Power-up & Measurement Procedure
1. Connect a jumper at JP1 terminals 1 and 2, connecting EN to GND, to disable operation.
2. Apply a 12V nominal input power supply (4.5V < V_IN < 18V) to the VIN and GND terminals.
3. Set the jumper at JP1 to connect terminals 2 and 3, connecting EN to VIN through resistor R30, to enable
operation.
4. Verify the output voltage (approximately 1.05V) between VOUT and GND.
5. Connect an external load up to 4A to the VOUT and GND terminals and verify the output voltage and current.
Output Voltage Setting
Set the output voltage with the resistive divider (R23, R28) between VOUT and GND with the midpoint at FB. The
output is set by the following formula:
VOUT = 0.765 x (1 + ^R23 )
R28
The installed V_OUT capacitors (C11, C12) are 22μF, 16V X5R ceramic types. Do not exceed their operating voltage
range and consider their voltage coefficient (capacitance vs. bias voltage) and ensure that the capacitance is
sufficient to maintain stability and provide sufficient transient response for your application. Installing a small 5pF to
22pF capacitor at C30 (in parallel with R23) may be desirable to improve transient response for higher output
voltages. See the RT7232 IC datasheet for more information.
UG7232GQW-00 April 2014
www.richtek.com
5