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PI2127-EVAL1 User Guide
Rev. 1.0
Page
4 of 9
Reference Designator
Value
Functional Description
C1, C2, C3, C4
Not installed
Snubber to reduce voltage ringing when the device turns off
C3
22μF
Output (Load) Capacitor
C6
2.2uF
Output (Load) Capacitor
D1, D2
LED
To indicate a fault exists when it is on
Q1, Q2
FJV1845
Constant Current bias circuit
R1, R2
Not Installed
Bias Circuit R
PG
, replaces constant current circuit
R3, R4
2.8K
Constant Current bias circuit, sets the current limiting
R5, R6,
1.5KΩ
LED current limit resistor, selected to operate at 3.3V and 5.0V logic voltage. Replace R5
and R6 with the proper resistor value for different logic voltage.
R7, R8
100K
Constant Current bias circuit
U1, U2
PI2127-01-LGIZ
Cool-ORing® SiP.
Table 3:
Component functional description
Test Procedure:
Initial Test Set Up
PI2127-EVAL1 designed with two bias circuit options,
bias resistor RPG (R1 and R2) and constant current
circuit. The constant current circuits are installed;
where R1 and R2 were not installed.
Leave enable inputs (EN1 and EN2) unconnected
(open).
Baseline Test Procedure – PI2127
(Refer to Figure 3)
1.
Recommended Material
1.1.
Material Needed-Picor supplied
1.1.1.
PI2127-EVAL1
1.1.2.
PI2127 Product Datasheet
1.2.
Recommended Users Supplied Equipment
1.2.1.
Two DC power supplies: 0-60V; 15A each.
1.2.2.
One low power logic voltage power supply
1.2.3.
Load: electronic Load, Power resistors or
actual load.
1.2.4.
Multimeter.
1.2.5.
Oscilloscope.
1.2.6.
Appropriately sized interconnect cables.
1.2.7.
Safety glasses.
Before initial power-up follow these steps to configure
the evaluation board for specific end application
requirements:
2.
EN inputs:
2.1.
Enable inputs (EN1 and EN2) were left
unconnected (open). PI2127 devices will be
enabled while enable pins are open. To disable
PI2127, connecting the enable input to return
(Vin-) with a hard wire or with an active device
(Transistor or MOSFET).
Leave EN1 and EN2
unconnected for the initial test.
3.
Control Circuitry Bias:
3.1.
The PI2127 control circuitry and the gate driver
for the internal MOSFET are biased through the S
pin. An internal regulator clamps the S pin
voltage with respect to PG pin (V
S-PG
) to 11.7V
typically. A bias resistor (R
PG
) or a Constant
Current bias circuit is required if the voltage at
the S pin is higher than the minimum Voltage
Clamp (V
S-CLM
, 11V). PI2127-EVAL1 has both
circuits laid out, but the constant current bias
circuit components are installed while R
PG
is not
installed.
