TEXAS

NSTRUMENTS

Load

Source

VIN

FAN

Source

V5IN

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Test Setup

4.2 Recommended Test Setup

Figure 3. TPS51916EVM-746 Recommended Test Setup

Figure 3 is the recommended test setup to evaluate the TPS51916EVM-746. When working at an ESD

workstation, ensure that any wrist straps, bootstraps, or mats are connected referencing the user to earth

ground before power is applied to the EVM.

Input Connections:

1. Prior to connecting the dc source V5IN, it is advisable to limit the source current from V5IN to 1 A

maximum. Ensure that V5IN is initially set to 0 V and connected as shown in Figure 3.

2. Prior to connecting the dc source VIN, it is advisable to limit the source current from VIN to 10 A

maximum. Ensure that VIN is initially set to 0 V and connected as shown in Figure 3.

3. Connect voltmeters V1 at TP2 (V5IN) and TP3 (GND) to measure V5IN voltage, V2 at TP5 (VIN), and

TP8 (GND) to measure VIN voltage as shown in Figure 3.

4. Connect a current meter A1 between dc source VIN and J2 to measure the input current.

5. Connect a current meter A2 between dc source V5IN and J1 to measure the input current.

Output Connections:

SLUU526–August 2011 Using the TPS51916EVM-746 Complete DDR2, DDR3, DDR3L, and DDR4

Memory Power Solution Synchronous Buck Controller, 2-A LDO, Buffered

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Configurations

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1. Connect the load to J5 and set the load to constant-resistance mode to sink 0 Adc before V5IN and

VIN are applied.

2. Connect a voltmeter V3 at TP11 (VDDQ) and TP14 (GND) to measure VDDQ voltage, V4 at TP12

(VTT) and TP13 (GND) to measure VTT voltage and V5 at TP17 (VTTREF) and TP18 (GND) to

measure VTTREF voltage.

Other Connections:

Place a fan as shown in Figure 3 and turn it on, ensuring that air is flowing across the EVM.

5 Configurations

5.1 S3, S5 Enable Selection

The controller can be enabled and disabled by switches SW1 and SW2.

Default setting: Push SW1 and SW2 to the bottom (OFF position) to disable the controller.

Table 2. S3, S5 Enable Selection

State SW2 (S3) set to SW1(S5) set to VDDQ VTTREF VTT

S0 ON position ON position ON ON ON

S3 OFF position ON position ON ON OFF(High-Z)

S4/S5 OFF position OFF position OFF(Discharge) OFF(Discharge) OFF(Discharge)

6 Test Procedure

6.1 Line/Load Regulation and Efficiency Measurement Procedure

1. Set up EVM as described in Section 4 and Figure 3.

2. Ensure that the load is set to constant-resistance mode and to sink 0 Adc.

3. Ensure that SW1 and SW2 are in the OFF position.

4. Increase V5IN from 0 V to 5 V. Use V1 to measure V5IN input voltage.

5. Increase VIN from 0 V to 12 V. Use V2 to measure VIN input voltage.

6. Push SW1 and SW2 to ON position to enable the controller.

7. Use V3 to measure VDDQ output voltage.

8. Use V4 to measure VTT output voltage.

9. Use V5 to measure VTTREF output voltage.

10. Use A1 to measure VIN input current for efficiency.

11. Use A2 to measure V5IN input current for efficiency.

12. Vary the load from 0 Adc to 20 Adc; VDDQ must remain in load regulation.

13. Vary VIN from 8 V to 20 V; VDDQ must remain in line regulation.

14. Push SW1 and SW2 to OFF position to disable the controller.

15. Decrease the load to 0 A.

16. Decrease VIN and V5IN to 0 V.

6.2 List of Test Points

Table 3. Test Point Functions

Test Points Name Description

TP1 PGOOD Power Good

TP2 V5IN 5-V input

TP3 GND Ground

Using the TPS51916EVM-746 Complete DDR2, DDR3, DDR3L, and DDR4 SLUU526– August 2011

Memory Power Solution Synchronous Buck Controller, 2-A LDO, Buffered

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Reference

0.001 0.01 0.1 1 10 100

I - Output Current - A

12 Vin

20 Vin

8 Vin

100

Efficiency - %

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Performance Data and Typical Characteristic Curves

Table 3. Test Point Functions (continued)

Test Points Name Description

TP4 S3 S3 signal input

TP5 VIN VIN input

TP6 VLDOIN_EXT External input for VLDOIN

TP7 S5 S5 signal input

TP8 GND Ground

TP9 GND Ground

TP10 SW Switching node

TP11 VDDQ VDDQ output

TP12 VTT VTT output

TP13 GND Ground

TP14 GND Ground

TP15 VREF Internal 1.8-V reference voltage

TP16 GND Ground

TP17 VTTREF Buffered VTT reference voltage

TP18 GND Ground

6.3 Equipment Shutdown

1. Shut down the load.

2. Shut down V5IN and VIN.

3. Shut down the fan.

7 Performance Data and Typical Characteristic Curves

Figure 4 through Figure 22 present typical performance curves for TPS51916EVM-746.

7.1 DDR3 VDDQ Efficiency

Figure 4. DDR3 VDDQ Efficiency

SLUU526–August 2011 Using the TPS51916EVM-746 Complete DDR2, DDR3, DDR3L, and DDR4

Memory Power Solution Synchronous Buck Controller, 2-A LDO, Buffered

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Reference

Part #	GRM32ER60J107ME20L
Description	CAP 100UF 6.3VDC X5R 20% SMD1210 - Cut TR (SOS) Additional Information:
Category	CAPACITOR
Availability	Out of Stock
Qty	0

GRM32ER60J107ME20L

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