Datasheet

SLUU171A - September 2003
14
TPS2350 −48-V Hot Swap/Supply Selector Evaluation Module
4 Using the EVM Kit to Evaluate the TPS2350
Procedures similar to the steps of Section 3.2.2 for functional test of the EVM can also be used to continue
evaluation of the TPS2350 hot swap controller device. Additional details about the EVM features are provided
in this section.
4.1 Supply Connections and Test Points
Supply connections to the EVM should be made to the banana jacks as shown in Figure 4. The two backplane,
48-V supplies (PS No. 1 and PS No. 2 in Figure 4) connect between J1 and J2 and J1 and J3, respectively. The
polarity of the circuit is such that the HI or (+) outputs of the supplies connect to J1, −48V_RTN. The LO or (−)
jacks connect to J2 (−48V_INA) and J3 (−48V_INB). PCB header J6 (VS) is used to connect an external pull-up
source when using the MOD_EN output of the EVM. This supply is referenced to the VOUT− node at J5.
The TPS2350 −48-V hot swap/supply selector EVM contains numerous test points located throughout the circuit
for waveform monitoring. A list of the EVM test points and their associated signals is given in Table 6.
Table 6. TPS2350 −48-V Hot Swap/Supply Selector EVM Test Points
TEST POINT SIGNAL NAME DESCRIPTION
TP2 FLT
Load fault output of the TPS2350. On the EVM, this signal drives
the red LED.
TP3 UV Sense input for supply undervoltage detection.
TP4 OV Sense input for supply overvoltage detection.
TP5 FLTTIM Fault timing waveform of the TPS2350.
TP6 RAMP Current ramp control output waveform.
TP7 SOURCE
Common source node of the selection FETs, and reference pin
for the TPS2350.
TP8 GATB Gate drive for the B supply selection FET.
TP9 GATA Gate drive for the A supply selection FET.
TP10 SNS Current sense input for the hot swap controller.
TP11 GAT Gate drive for the hot swap or pass FET Q1.
TP12 PG
Open-drain, active-high indication of a load power-good condi-
tion.
TP13 −VINB
Selection comparator voltage sense input for the B−designated
supply. On the EVM, this is connected to the −48V_INB jack.
TP14 −VINA
Selection comparator voltage sense input for the A−designated
supply. On the EVM, this is connected to the −48V_INA jack.
TP15 SOURCE
Secondary test point on the TPS2350 reference node (located
near the timing capacitors).
TP16 −48V_RTN
Backplane side of the high side of input power to the board. This
node is common to both supplies.
TP17 VOUT+
Additional supply high side test point on the plug-in side of the
POWER switch (S2). This is also the input supply to the
TPS2350 and the high-side of the load
TP18
−48V_INA
Low side input of the A−designated power supply.
TP19
−48V_INA Low side input of the A−designated power supply.
TP20
−48V_INB
Low side input of the B−designated power supply.
TP21
−48V_INB Low side input of the B−designated power supply.
TP22
VOUT+
High side of switched (load) output power.
TP23
VOUT+ High side of switched (load) output power.
TP24
VOUT−
Low side of switched (load) output power.
TP25
VOUT− Low side of switched (load) output power.