Complete Flip-up Display Solution for Automotive Infotainment

Figure 1 - Automotive infotainment flip-up display

In the automotive market, built-in infotainment displays are becoming a must for many consumers. These displays can take up a large amount of real estate on the dashboard. An alternative is to add a flip-up display. Unfortunately, designing the bi‑directional motor control circuits and voltage converters can take a lot of time. For convenience I suggest taking a look at Texas Instruments' (TI's) automotive ready actuator solution for flip-up infotainment displays.

For this display solution, TI has combined several "Q1" automotive ready devices to help ease the development and time to market. The display deploys in less than 5 seconds and best of all no additional software is required. The block diagram below illustrates the complete system:

Figure 2 – TI's flip-up display solution

Power Supply
TI started with the TPS65320-Q1 power supply integrated circuit (IC). It is a combination of a High-Vin Buck converter (DC/DC step down) and a Low-Dropout Voltage (LDO) regulator.

Figure 3 - TPS65320-Q1

The Buck converter has a wide input voltage range between 3.6 V to 40 V and an adjustable output voltage range between 1.1 V to 20 V. Additionally, the chip operates with an output load current of 3.2 A and a standby current, in low load conditions, of 40 µA to help conserve power. For design flexibility, the TPS65320-Q1 has a switching frequency of 100 kHz to 2.5 MHz. Lastly, the chip has built in overcurrent and over temperature protection.

As always, TI has supplied technical documentation to support your development such as datasheets, with a list of features and application notes, complete with a design checklist.

Figure 4 - Schmitt-Trigger
inverter

The Logic System
TI used a SN74LVC2G14-Q1 dual Schmitt-Trigger inverter to clean up the signal from the ON/OFF switch. This controls power to a combination of logic devices listed below:

LVC2G74-Q1 – D-Type Flip-Flop
SN74LVC1G32-Q1 – 2-input positive OR gate
LVC3G08-Q1 – Dual 2-input AND gate

The logic devices are used to read the Open/Close signals and send signals to the motor controller.

The TPS3809I50-Q1, a supply voltage supervisor, provides circuit initialization and timing supervision to the logic system.

Motor Control
The final piece of the puzzle is the DRV8832-Q1. It is a low-voltage, bi-directional motor driver IC. It uses the signals from the logic system to control the direction and movement of the motor. Not only is this chip an excellent choice for this application, it can also be used to control stepper-motors, small pumps, actuators and other loads.

The DRV8832-Q1 uses pulse width modulation (PWM) to maintain a constant motor speed with the varying input voltages (2.75v to 6.8v) that can occur in automotive systems. It also has a current limit condition that protects the motor in cases of startup, stall or fault. To make the IC safe and reliable for automotive uses internal protections provide overcurrent, short circuit, under voltage lockout, and over temperature protection.

Conclusion
TI provides a complete solution for hidden displays that are safe for the automotive industry. Though these displays are designed for automotive applications; they are small enough to be used for security systems or other hand-held devices. Using TI's solution will simplify your designs and reduce your time to market.

Texas Instruments has sponsored promotion of their automotive infotainment solutions on ENGINEERING.com. They have no editorial input to this post - all opinions are mine. Christine Halsey