3.
3V
PW
R
unsupplied
Supplied
by VREG
3.
3V
PW
R
1.2
V P
WR
Disconnected
from VREG
Supplied by
VREG, remove
before installing
BRIDGE-jumper!
1.2
V P
WR
BRIDGE
Disconnected
from 3.3V rail
Supplied by 3.3V rail .
Remove 1.2V_PWR-
jumper before
installation
BRIDGE
Setup
3.3V_PWR – Supplies the Collector of the external bipolar transistor of the 3.3V rail. Installing connects it
to VREG (5.3V-output of the Buck-regulator). If uninstalled, the transistor in not powered (Note: at light
loads, the base-current may be sufficient to supply the output, but adding a load causes V
OUT
to drop).
Figure 4. 3.3V PWR Jumper Settings
1.2V_PWR - Supplies the Collector of the external bipolar transistor of the 1.2V rail. Installing connects it
to VREG (5.3V-output of the Buck-regulator). If uninstalled, the transistor in not powered (Note: at light
loads, the base-current may be sufficient to supply the output, but adding a load causes V
OUT
to drop). An
alternative to supply the 1.2V rail is to install the jumper on BRIDGE (see
), but make sure to
never have both jumpers (1.2V_PWR and BRIDGE) installed at the same time.
Figure 5. 1.2V PWR Jumper Settings
JP6 – Bridge - Supplies the Collector of the external bipolar transistor of the 1.2V rail. Installing connects
it to the 3.3V LDO-output. If connected, consider the extra current drawn from the 3.3V rail, which must be
supported by the power-dissipation of the 3.3V-transistor! Make sure to never have both jumpers
(1.2V_PWR and BRIDGE) installed at the same time.
Figure 6. Bridge Jumper Settings
4
TPS65300EVM
SLVU685 – February 2012
Copyright © 2012, Texas Instruments Incorporated