TLV767-Precision Voltage Regulator

Voltage regulators are a crucial part of the electronic and electrical circuit for there proper operation. These are available as fixed output voltage versions and as adjustable output voltage forms. One of such 16V precision voltage regulator is TLV767. The TLV767 is a linear voltage regulator. It has low quiescent current and High PSRR value. It is capable of handling 1 A of load current. Applications with very sensitive power-supply rails use this device.TLV767 contains integrated foldback current limit circuit, output-enable circuit, thermal shutdown circuit, and Undervoltage lockout circuit. TLV767 is well-known for excellent line and load transient performance.

TLV767 Block Diagram

The block diagram of TLV767 is shown below.

Output Enable

When the voltage of the enable pin is greater than the high-level input voltage of the EN pin, the output voltage is enabled. The output is disabled when the enable pin voltage is less than the low-level input voltage of the EN pin.

The EN pin can be left floating to enable the device as it contains internal pull-up current on EN pin.

Dropout Voltage

When the pass transistor is fully on, at the rated output current, the difference between the input voltage and the output voltage is known as dropout voltage.

Foldback Current Limit

To protect the device from transient high-load current faults, the device has an internal current limit circuit. The current limit is a hybrid high-wall foldback scheme. When the device is in current limit the output voltage is not regulated.

Undervoltage Lockout

To monitor the input voltage and to allow controlled and consistent turn on and turn off of the output voltage, the device has an independent Undervoltage lockout circuit.

Thermal Shutdown

The device contains a thermal shutdown protection circuit to disable the circuit when the junction temperature exceeds the recommended value.

How to Use?

There are some steps to be followed while using TLV767 voltage regulator.

Adjustable Device Feedback Resistors

To set the output voltage in the adjustable version device, external feedback divider resistors are required. The setting is done according to the following equation:-

V-OUT = V-FB x (1+ R1/R2).

Recommended Capacitor Types

Low equivalent series resistance ceramic capacitors at input and output are used to make the device stable. Good capacitive stability across temperature can be provided with capacitors that employ X7R, X5R and C0G- rated dielectric materials.

Input and Output Capacitors Requirements

If the source impedance is more than 0.5Ω  an input capacitor is recommended. If the large fast rise-time line and load transients are anticipated, larger values of capacitors can be used.

Output capacitor increases the dynamic performance of the device.

Reverse Current

The device gets damaged due to excessive reverse current. In this device reverse current is not internally limited. An external limiting system has to be used when a high reverse current is anticipated.

Feedforward capacitor

This capacitor improves the transient, noise, PSRR performance of the device. For adjustable voltage versions, this is connected from OUT pin to the FB pin.

Power Dissipation

The PCB area around the regulator should not contain any heat generating devices that can cause added thermal stress. Power dissipation here depends on the load conditions as well as the input-to-output voltage difference.

The maximum allowable ambient temperature of the device is determined by the power dissipation value of the device.

Pin Configuration of TLV767

TLV767 is available as both an adjustable version and fixed output voltage version. These two have the same type of packaging but their pin configurations differ.

The Pin configuration of 6-Pin WSON DRV package for adjustable version is as follows-

• Pin-1 is the output pin OUT. An output capacitor of the recommended value is attached to this pin.
• Pin- 2 is the feedback pin FB. This pin acts as input to the error amplifier. This pin also used to set the output voltage of the device with the use of external resistors.
• Pin-3 and Pin-5 are ground pins GND.
• Pin-4 is the enable pin EN. Driving this pin high enables the device. This pin contains an internal pull-up resistor and can be left floating to enable the device or can be connected to the input pin.
• Pin-6 is the input pin IN.
• The thermal pad is given for the protection of the device.

For pin Configuration of Fixed version, all pins are similar to adjustable version except the Pin -2. Here pin-2 is used as output sense pin instead of feedback pin. This pin is connected to the output pin.

Specifications

The specifications of TLV767 are as follows-

• The input voltage range is from 2.5V to 16V.
• These are available as both an adjustable voltage version and fixed voltage version.
• The output voltage range for the adjustable version is from 0.8V to 13.6V.
• Fixed voltage version has the output voltage range from 0.8V to 6.6V.
• TLV767 has a 1% accuracy over the load and temperature.
• This device has a low I_Q of 50 µA.
• TLV767 has an internal soft start time of 500µs.
• This device has Fold-back current limiting.
• TLV767 contains a thermal protection circuit.
• This device work in a stable state when 1-µF ceramic capacitors are used with the circuit.
• This regulator has high PSRR of 70dB at 1kHz and 46dB at 1 MHz.
• Available as a 6-pin 2 mm x 2mm WSON package.
• Maximum output current is internally limited.
• Operating junction temperature is from -50°C to 150°C.
• Storage temperature range is from -65°C to 150°C.
• Under recommended operating conditions the enable voltage range is from 0V to 16V.
• The preferred output capacitor value is 2.2 µF.
• The input capacitor value is 1µF.
• For adjustable device feed-forward capacitor of 10pF is used.
• Minimum feedback driver current of the adjustable version is 5µF.

Applications of TLV767

Applications of TLV767 are as follows-

• TLV767 is applied in TVs, Monitors.
• This device is used in appliances.
• Motor drive control boards use TLV767.
• Low voltage microcontrollers, processors.
• PC peripherals, notebooks, motherboards make use of TLV767 regulator.
• Printers also contains TLV767 voltage regulator.
• TLV767 voltage regulators are used in WiFi access points and router circuits.

Alternative IC

Some of the IC available in the market that can be used as an alternative to TLV767 are TLV758P, LM1117, LP5907, TLV1117, TPS795, LP5912, TPS7A90 etc…

The electrical characteristics of TLV767 under various temperature conditions can be found in the datasheet given by Texas Instruments. Which of the characteristic of TLV767 proved more helpful to you in your application?

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Texas instruments