Texas Instruments TPS54226EVM-539, Руководство пользователя

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O O
R1
V = (0.763 + 0.0017 V ) 1+
R2
æ ö
´ ´ ç
÷
è ø
(2)
Table 1-3 lists the R1 value for some common output voltages. For higher output voltages, a feedforward
capacitor is required. Pads for this component (C2) are provided on the printed circuit board. C2 is used for
faster load transient response and is recommended for auto skip mode stability. Note that the values given in
Table 1-3 are standard values, and not the exact value calculated using Table 1-3 .
Table 1-3. Output Voltages
OUTPUT VOLTAGE (V) R1 (kΩ) R2 (kΩ) C2 (pF) L1 (µH)
1.0 6.81 22.1 2.2
1.05 8.25 22.1 2.2
1.2 12.7 22.1 2.2
1.8 30.1 22.1 150 – 220 3.3
2.5 49.9 22.1 68 – 100 3.3
3.3 73.2 22.1 47 – 68 3.3
5.0 121 22.1 33 – 47 4.7
2 Test Setup and Results
This section describes how to properly connect, set up, and use the TPS54226EVM-539. The section also
includes test results typical for the evaluation modules and the following:
• Efficiency
• Output load regulation
• Output line regulation
• Load transient response
• Output voltage ripple
• Input voltage ripple
• Start-up
• Switching frequency
2.1 Input/Output Connections
The TPS54226EVM-539 is provided with input/output connectors and test points as shown in Table 2-1 . A power
supply capable of supplying 2 A must be connected to J1 through a pair of 20 AWG wires. The load must be
connected to J2 through a pair of 20 AWG wires. The maximum load current capability is 2 A. Wire lengths must
be minimized to reduce losses in the wires. Test point TP1 provides a place to monitor the V
IN
input voltages
with TP2 providing a convenient ground reference. TP8 is used to monitor the output voltage with TP9 as the
ground reference.
www.ti.com Test Setup and Results
SLVU336A – NOVEMBER 2009 – REVISED OCTOBER 2021
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