Texas Instruments TPS65291 EVM, Руководство пользователя

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Getting Started
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8 SLVUB61 – July 2017
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TPS65291 EVM User's Guide
2.5 EVM Operation
This section describes the power-on procedure and the software instructions to enable BUCK1 and
LDO_SW. When these procedures are complete, a load can be applied in parallel to the multi-meter
shown in
Figure 3 .Probes can be placed on any test point in Table 1 to evaluate the full performance of
the TPS65291 device.
2.5.1 Power-On Procedure
After setting up the hardware to match the test setup shown in Figure 3 , follow these instructions to verify
the voltage on the always-on BUCK2 rail:
• Set the input supply voltage to 6V and ensure it is off before connecting to the EVM.
• Connect the power supply return lead (the black cable) to the J9 header.
• Apply the input power lead (the red cable) to J1 and a jumper cable from J1 to J2.
• Ensure that the current limit on the supply is 1.5 A.
• Connect the voltage lead of digital multi-meter (DMM) to B2_VOUT (J6) and connect the GND lead to
J12.
• Turn the power supply on and observe the voltage on the DMM measuring J6 (B2_VOUT):
– Measure (with the DMM) and verify the BUCK2 output voltage at J6 is approximately 2.8 V.
• Move the voltage lead of the DMM to J11 (LDO_SW_VOUT):
– Measure (with the DMM) and confirm that LDO_SW is disabled.
• Move the voltage lead of the DMM to J7 (B1_VOUT):
– Measure (with the DMM) and confirm that BUCK1 is disabled.
2.5.2 Software Instructions to Enable BUCK1 and LDO_SW
After verifying the operation of BUCK2, follow these instructions to enable BUCK1 and LDO_SW:
• Click the Read All button and verify that some values other than 0x00 (hexadecimal) appear in the
Register0 row of the register map table, as shown in Figure 5 .
• Click the Read All button again and most blue highlighted '1's will turn white or gray, indicating that
these bits have not changed since the last time they were read.