CSD87350Q5D datasheet(14/49 Pages) TI1

14 / 49 page

www.ti.com

Test Procedure

NOTE:

The IOUT_CAL_GAIN parameter is used by the TPS40422 in the calculation of output

current level, and this number is the dc resistance of the output inductor. Although this

number can be reconfigured, a number entry that does not match the actual DCR of the

inductor on the EVM will result in current reporting inaccuracy. This also affects OC Fault

and OC Warn performance.

The TON_RISE parameter may affect proper start-up if the rise time and output capacitance

bank result in a current that exceeds the OC Fault level. The start-up surge current in the

output capacitance bank is added to the load current, so the sum of these two currents must

be less than the OC Fault level for proper start-up.

Test Procedure

6.1

Line/Load Regulation and Efficiency Measurement Procedure

1. Set up the EVM as described in Section 4.3 and Figure 2.

2. Ensure that both electronic loads are set to draw 0 Adc.

3. Increase Vin from 0 V to 12 V using DMM1 to measure input voltage.

4. Use DMM2 to measure output voltage Vout1.

5. Vary the load from 0 Adc to 20 Adc. Vout1 must remain in regulation as defined in Table 1.

6. Vary Vin from 8 V to 14 V. Vout1 must remain in regulation as defined in Table 1.

7. Decrease the load to 0 A.

8. Use DMM3 to measure output voltage Vout2.

9. Vary the load from 0 Adc to 15 Adc. Vout1 must remain in regulation as defined in Table 1.

10. Vary Vin from 8 V to 14 V. Vout2 must remain in regulation as defined in Table 1.

11. Decrease the load to 0 A.

12. Decrease Vin to 0 V.

6.2

Control Loop Gain and Phase Measurement Procedure

The PWR091EVM includes a 49.9-

Ω series resistor in the feedback loop for both Vout1 and Vout2. These

resistors are used for loop response analysis and are accessible at the test points TP8 and TP9 for Vout1,

and TP10 and TP12 for Vout2. Those test points must be used during loop response measurements as

the injection points for the loop perturbation. See the short descriptions listed in Table 4.

Table 4. List of Test Points for Loop Response Measurements

Test Point

Node Name

Description

Comment

Input to feedback divider of

The amplitude of the perturbation at this node must be limited to

TP8

INPUT1

Vout1

less than 100 mV.

Bode plot data can be measured by a network analyzer as

TP9

OUTPUT1

Resulting output of Vout1

TP9/TP8.

Input to feedback divider of

The amplitude of the perturbation at this node must be limited to

TP12

INPUT2

Vout2

less than 100mV.

Bode plot data can be measured by a network analyzer as

TP10

VOUT2

Resulting output of Vout2

TP10/TP12.

Measure only one output at a time with the following procedure:

1. Set up the EVM as described in Section 4.3 and Figure 2.

2. For Vout1, connect the network analyzer

’s isolation transformer from TP8 to TP9.

3. Connect the input signal measurement probe to TP8. Connect output signal measurement probe to

TP9.

4. Connect the ground leads of both probe channels to TP4.

5. On the network analyzer, measure the Bode plot data as TP9/TP8 (Out/In). The frequency sweep must

SLVU638

– January 2012

Using the PWR091EVM Dual-Output DC/DC Analog With PMBus Interface

Submit Documentation Feedback

CSD87350Q5D bảng dữ liệu(PDF) 14 Page - Texas Instruments

CSD87350Q5D bảng dữ liệu(HTML) 14 Page - Texas Instruments

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49

bảng dữ liệu tải về

Link URL