Bench Test Setup Conditions
shows the jumpers and switches for the EVM.
Table 3. Jumpers and Switches
Jumper
Function
Placement
Comment
Number
JP1
Buck1 enable (EN1)
Connect EN1 to GND to disable Vout1, connect EN1 to
Vin through a 100-k
Ω
resistor to enable Vout1; Leave
open to enable Vout1
JP2
Buck2 enable (EN2)
Connect EN2 to GND to disable Vout2, connect EN2 to
Vin through a 100-k
Ω
resistor to enable Vout2; Leave
open to enable Vout2
JP7
I
2
C address
I
2
C address configuration pin. Connect this pin to GND
On board Vcc is 6.25 V
to set address 0x60H; connect it to Vcc to set address
0x61H; leave it open to set address 0x62H
JP8
Mode
Operation mode control pin. Connect this pin to GND to
set forced PWM mode; leave the pin open to set auto
PSM-PWM; connect this pin to Vcc, set the IC to run in
current share mode.
JP9
I
2
C Power
Power connected to the I
2
C IO pull-up resistor; Leave
On board Vcc is 6.25 V
the two pins un-connected set the power to be 3.3V from
the I
2
C interface adaptor; short the two pins set the
power to be Vcc.
JP15
I
2
C interface connector
Pin 5 is 3.3 V from adaptor; pin 6 is Ground; pin 9 is
SCL, pin 10 is SDA.
5.2
Hardware Requirement
This EVM requires an external power supply capable of providing 4.5 V to 18 V at 7 A.
A function generator capable of driving the SYNC pin with 0.4- to 3.3-V amplitude and a 200-kHz to 1.6-
MHz square wave signal is required for synchronization. The EVM kit includes a USB-TO-GPIO interface
box which, when installed on a PC and connected to the EVM, allows communication with the EVM via a
GUI interface. The minimum PC requirements are:
•
Windows
®
2000 or Windows XP operating system
•
USB port
•
Minimum of 30 MB of free hard disk space (100 MB recommended)
•
Minimum of 256 MB of RAM
5.3
Hardware Setup
After connecting the power supply to J1, turn on the power supply, and connect JP1 to Vin through a 100-
k
Ω
resistor, connect JP2 to Vin through a 100-k
Ω
resistor, connect JP7 to GND, connect JP8 to GND, the
EVM will regulate the output voltages to the values shown in
. Additional input capacitance may be
required in order to mitigate the inductive voltage droop that may occur during a load transient event.
The output voltage is changed by sending the digital control signal via a PC running the TPS65276V
controller software and USB-TO-GPIO interface box. Change the output voltage with the following steps:
•
Connect one end of the USB-TO-GPIO box to the PC using the USB cable and the other end to JP15
of the TPS65276V using the supplied 10-pin ribbon cable as shown in
. The connectors on the
ribbon cable are keyed to prevent incorrect installation.
•
Connect the power supply on J1, and turn on the power supply.
•
Run the software as explained in the next section.
8
4.5-V to 18-V Input, Dual (6.5-A and 3.5-A) Synchronous Step-Down
SLVU878 – February 2013
Converter With I
2
C Controlled VID and Current Sharing Evaluation Module
Copyright © 2013, Texas Instruments Incorporated