Texas Instruments TPS650231EVM, TPS65023B manual Modifications, Setting the Output Voltage

Models: TPS65023B TPS650231EVM

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Input/Output Connector Description

4.Connect the ribbon cable between the EVM and the USB-TO-GPIO (HPA172) adapter.

5.Connect the USB cable between the computer and the HPA172EVM.

6.Turn on all supplies.

7.Run the TPS65023B/TPS650231EVM software

3.2Modifications

3.2.1Setting the Output Voltage

The TPS65023B features two default output voltages. These output voltages can be selected by pulling DEFDCDC2 high – selecting the higher default output voltage – or pulling DEFDCDC2 low – selecting the lower default output voltage.

In addition, the output voltage of DCDC2 can be externally adjusted with the resistor divider network R3 and R6. The default configuration of the TPS65023BEVM-664 is that R3 and R6 are not assembled. The default output voltage of DCDC2 can be selected with JP2.

Note that the default output voltage is selected once at startup of the device. Changing logic level of DEFDCDC2 during operation does not affect the output voltage and is not allowed.

3.2.2Setting the Output Voltage for DCDC2, TPS650231

The TPS650231 does not feature these default output voltages. The output voltages of DCDC2 is externally adjustable only. The default configuration of the TPS650231EVM-664 is that R3 and R6 are not assembled. JP2 is not assembled.

TPS650231 does not have the default output voltage feature, and this provides the benefit of external voltage scaling options.

3.2.3Simple Two-Point Voltage Scaling, TPS650231

DCDC2 does not have the previously described preset default output voltages. An external voltage scaling circuit is on the EVM, and the output voltage of DCDC2 can be switched between two preset voltages. This useful feature reduces the power consumption of an application processor in Low Power mode.

The voltage scaling circuit consists of JP2,Q1, R3, R6, and R24. The circuit uses a transistor (Q1) to connect a resistor (R24) in parallel to the lower resistor of the feedback network (R6) of DCDC2.

Modifying the resistor network by paralleling R24 and R6 reduces the overall resistance of the lower resistor and therefore increases the output voltage of the DC/DC converter. See Equation 1 and Equation 2 to design R24. In the factory configuration, the components JP2, Q1, and R24 are not assembled on the board.

3.2.4Scaling the Output Voltage of DCDC2 From LDO2

Another approach to scale the DC/DC converter output voltage is to use an external adjustable voltage. Any external adjustable voltage source can be used, e.g., output voltage of an digital-to-analog converter. In the TPS65023B/TPS650231, LDO1 and LDO2 can be adjusted via I2C. The TPS65023B/TPS650231 provides the ability to feed the output voltage of LDO2 back to the resistor divider network, using R25, and therefore scale the output voltage of DCDC2 based on the LDO2 output voltage.

In this configuration, R25, R3, and R6 need to be assembled. R24, R26, Q1, and R3 need to be removed.

VOUT _ DCDC2 = V _ REF × (1 + R1 )) + (V _ REF − VLDO2) × ( R1 )

R2

R3

(1)

From Equation 2 it can be seen that maximum DCDC1 output voltage occurs for minimum VLDO2, and minimum DCDC1 output voltage occurs for maximum VLDO2.

To ensure that the desired DCDC1 output voltages can be adjusted, design the resistors R25, R3, and R6 according to and Equation 2 and Equation 2.

SLVU394 –October 2010

TPS65023B/TPS650231EVM

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Copyright © 2010, Texas Instruments Incorporated

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Texas Instruments TPS650231EVM, TPS65023B manual Modifications, Setting the Output Voltage for DCDC2, TPS650231

TPS65023B, TPS650231EVM specifications

Texas Instruments has a reputation for producing high-quality power management solutions, and the TPS650231EVM and TPS65023B are perfect examples of this. These advanced power management modules are designed for efficient power delivery in various applications, including portable devices and embedded systems.

The TPS650231EVM is an evaluation module developed to facilitate the evaluation of the TPS65023B power management IC. This device is specifically engineered to deliver power to processors that require multiple outputs from a single power source. The TPS65023B integrates several key features that make it a robust choice for designers aiming to simplify their power management requirements.

One of the main highlights of the TPS65023B is its dual buck converter. This converter can efficiently convert the input voltage into multiple output voltages, specifically optimized for powering processors and other system components. The device supports adjustable output voltages, allowing developers to tune the system to meet the exact power needs of their applications. With an input voltage range of 2.5V to 5.5V, the TPS65023B can accommodate diverse power input requirements.

Another key technology incorporated in the TPS65023B is the ultra-low quiescent current specification, which helps extend battery life in portable applications. This is particularly important in battery-powered devices, where optimization of power consumption is critical. The device also incorporates various protection features, including thermal shutdown, over-voltage protection, and short-circuit protection, ensuring reliable operation under various conditions.

The TPS65023B features a small footprint, making it ideal for space-constrained designs. The integration of multiple power management functions into a single device not only saves board space but also simplifies the design process, allowing engineers to focus on other critical aspects of their applications.

In addition to its technical specifications, the TPS650231EVM provides a user-friendly platform for evaluating the performance of the TPS65023B. This evaluation module includes necessary components and design considerations, enabling developers to quickly assess the device's capabilities within their systems.

In summary, the Texas Instruments TPS650231EVM and TPS65023B offer cutting-edge features, advanced technology, and robust performance. Their versatility and efficiency make them highly suitable for a range of applications, helping engineers achieve their design goals while maximizing power efficiency and reliability.