Datasheet
BUF08821EVM-USB Hardware Overview
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Table 4 summarizes the function of the USB_DIG_Platform jumpers. For most applications, the default
jumper position should be used. A separate document (SBOU058) gives details regarding the operation
and design of the USB_DIG_Platform.
Table 4. USB_DIG_Platform Jumper Functions
Jumper Default Purpose
This jumper selects external power or bus power.
External power is applied on J5 or T3 (9V dc). Bus
JUMP1 EXT
power is 5V from the USB bus. External power is
typically used because the USB Bus power is noisy.
JUMP2 EXT Same as JUMP1.
This jumper determines where the TUSB3210 will
load the USB_DIG_Platform firmware upon
JUMP3 EE ON
power-up or reset. The EE Off position is used for
development for development or firmware update.
This jumper sets the address for the USB board.
JUMP4, JUMP5 L, L The only reason to change from the default setting
is if multiple boards are being used.
This jumper selects the voltage of the device under
test supply (V
DUT
= 5V or 3V). This jumper is
JUMP9 5V
typically the only jumper that is changed for most
applications.
JUMP10 WP ON This write protects the firmware EEPROM.
JUMP11 WP ON This write protects the calibration EEPROM
Uses the regulator output to generate the V
DUT
JUMP13 REG supply. The USB bus can be used as the V
DUT
supply.
Uses the external power (9V as opposed to the
JUMP14 9V
bus)
While in the BUS position V
DUT
operation is normal.
While in the V
RAW
position the V
DUT
supply is
JUMP17 BUS
connected to an external source. This configuration
allows for any value of V
DUT
between 3V and 5V.
(1)
Connects the pull-up on GPIO to the V
DUT
supply or
JUMP18 V
DUT
the V
CC
supply.
(1)
CAUTION: Adjusting outside of this range will damage the EVM.
3.7 BUF08821EVM-USB Features
This section describes some of the hardware features present on the BUF08821EVM-USB board.
3.7.1 BKSEL: OTP Bank Selection Switch
The BKSEL switch located on the BUF08821EVM-USB board selects the memory bank to be used when
operating the EVM. Bank 0 selects the gamma curve that is stored in Bank_0 of the BUF08821. Bank 1
selects the gamma curve that is stored in Bank_1 of the BUF08821. This switch also determines the OTP
bank that is written to by the BUF08821EVM-USB software. Note that this switch is not active if JMP3 is
set to EXT.
3.7.2 JMP1: I
2
C SCK Control Setting
Jumper JMP1 selects where the BUF08821 I
2
C SCL pin is connected. If JMP1 is set in the INT position,
the I
2
C clock signal is generated from the I2C_SCK_ISO signal from the USB_DIG_Platform.
When JMP1 is set in the EXT position, an external source connected to SCL pin of terminal T4 can be
used to provide the I
2
C SCK signal for the BUF08821.
12
BUF08821EVM-USB User Guide and Software Tutorial SBOU095–March 2011
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