How to Use Adafruit TPS61169: Examples, Pinouts, and Specs

Design with Adafruit TPS61169 in Cirkit Designer

Introduction

The Adafruit TPS61169 is a high-efficiency boost converter designed to step up low input voltages to higher output voltages. This component is ideal for applications requiring a compact and efficient power supply solution, such as powering LEDs, OLED displays, or other devices from batteries or low-voltage sources. It features adjustable output voltage, high output current capability, and built-in protection features, making it versatile and reliable for a wide range of projects.

Explore Projects Built with Adafruit TPS61169

Battery-Powered Arduino UNO Smart Light with NeoPixel and ADXL345

This circuit is a battery-powered system featuring an Arduino UNO that controls an Adafruit NeoPixel Stick and interfaces with an ADXL345 accelerometer and an ILI9341 TFT display. The TP4056 module charges a 18650 battery, which powers the system through a DC-DC converter. The Arduino code drives the NeoPixel Stick to display a red light sequence.

Open Project in Cirkit Designer

Battery-Powered Smart Sensor Hub with Adafruit QT Py RP2040

This circuit features an Adafruit QT Py RP2040 microcontroller interfaced with an APDS9960 proximity sensor, an MPU6050 accelerometer and gyroscope, and an OLED display via I2C communication. It also includes a buzzer controlled by the microcontroller and is powered by a 3.7V LiPo battery with a toggle switch for power control.

Open Project in Cirkit Designer

Battery-Powered Raspberry Pi Pico GPS Tracker with Sensor Integration

This circuit is a data acquisition and communication system powered by a LiPoly battery and managed by a Raspberry Pi Pico. It includes sensors (BMP280, MPU9250) for environmental data, a GPS module for location tracking, an SD card for data storage, and a WLR089-CanSAT for wireless communication. The TP4056 module handles battery charging, and a toggle switch controls power distribution.

Open Project in Cirkit Designer

Battery-Powered Smart Light with Proximity Sensor and OLED Display using Adafruit QT Py RP2040

This circuit is a portable, battery-powered system featuring an Adafruit QT Py RP2040 microcontroller that interfaces with an OLED display, a proximity sensor, an accelerometer, and an RGB LED strip. The system is powered by a lithium-ion battery with a step-up boost converter to provide 5V for the LED strip, and it includes a toggle switch for power control. The microcontroller communicates with the sensors and display via I2C.

Open Project in Cirkit Designer

Common Applications

Driving high-power LEDs or LED arrays
Powering OLED displays or LCD backlights
Boosting battery voltage for portable devices
General-purpose DC-DC boost conversion

Technical Specifications

The Adafruit TPS61169 is based on the Texas Instruments TPS61169 IC and comes with the following key specifications:

Parameter	Value
Input Voltage Range	2.7V to 18V
Output Voltage Range	Adjustable up to 38V
Maximum Output Current	1.2A (dependent on input voltage and configuration)
Switching Frequency	1.2 MHz
Efficiency	Up to 90%
Feedback Voltage	200 mV
Operating Temperature	-40°C to +85°C
Package Type	SOT-23-6

Pin Configuration

The Adafruit TPS61169 module has six pins, as described in the table below:

Pin Name	Pin Number	Description
VIN	1	Input voltage pin. Connect to the power source (2.7V to 18V).
GND	2	Ground pin. Connect to the system ground.
FB	3	Feedback pin. Used to set the output voltage via an external resistor divider.
EN	4	Enable pin. Drive high to enable the converter, low to disable it.
SW	5	Switch pin. Connect to the inductor and diode.
VOUT	6	Output voltage pin. Connect to the load and output capacitor.

Usage Instructions

How to Use the Adafruit TPS61169 in a Circuit

Power Supply: Connect the input voltage (2.7V to 18V) to the VIN pin. Ensure the input voltage is within the specified range.
Inductor Selection: Choose an appropriate inductor value (typically 4.7 µH to 22 µH) based on your desired output voltage and current.
Output Voltage Adjustment: Use a resistor divider network connected to the FB pin to set the desired output voltage. The formula for the output voltage is: [ V_{OUT} = V_{FB} \times \left(1 + \frac{R1}{R2}\right) ] where ( V_{FB} ) is the feedback voltage (200 mV), and ( R1 ) and ( R2 ) are the resistors in the divider.
Enable Pin: Drive the EN pin high (logic level) to enable the boost converter. Pull it low to disable the device.
Output Capacitor: Connect a low-ESR capacitor (e.g., 10 µF or higher) to the VOUT pin to stabilize the output voltage.
Diode Selection: Use a fast-recovery Schottky diode (e.g., 1N5819) between the SW pin and VOUT to handle the switching current.

Example Circuit

Below is a basic circuit diagram for using the Adafruit TPS61169 to drive an LED:

VIN (Battery) -----> [TPS61169 VIN]
                     [TPS61169 GND] -----> System Ground
                     [TPS61169 SW] -----> Inductor -----> Diode -----> LED -----> VOUT
                     [TPS61169 FB] -----> Resistor Divider -----> System Ground
                     [TPS61169 EN] -----> Logic High (Enable)

Arduino Example Code

The Adafruit TPS61169 can be used with an Arduino to control the enable pin. Below is an example code snippet:

// Define the enable pin for the TPS61169
const int enablePin = 7;

void setup() {
  // Set the enable pin as an output
  pinMode(enablePin, OUTPUT);

  // Enable the TPS61169 by setting the pin HIGH
  digitalWrite(enablePin, HIGH);

  // Optional: Add a delay to allow the boost converter to stabilize
  delay(100);
}

void loop() {
  // Example: Toggle the enable pin to turn the boost converter on and off
  digitalWrite(enablePin, HIGH);  // Enable the TPS61169
  delay(5000);                   // Keep it on for 5 seconds
  digitalWrite(enablePin, LOW);  // Disable the TPS61169
  delay(5000);                   // Keep it off for 5 seconds
}

Best Practices

Use low-ESR capacitors for both input and output to minimize voltage ripple.
Ensure proper thermal management, as the device can heat up under high load conditions.
Keep the feedback resistor divider close to the FB pin to reduce noise.
Use short and wide traces for the power connections to minimize resistance and inductance.

Troubleshooting and FAQs

Common Issues and Solutions

No Output Voltage:
- Ensure the EN pin is driven high to enable the device.
- Verify that the input voltage is within the specified range (2.7V to 18V).
- Check the connections for the inductor, diode, and output capacitor.
Output Voltage is Incorrect:
- Double-check the resistor values in the feedback divider network.
- Ensure the feedback pin (FB) is properly connected to the resistor divider.
Device Overheating:
- Verify that the inductor and diode are rated for the required current.
- Check for excessive input or output current beyond the device's specifications.
High Output Ripple:
- Use low-ESR capacitors for the output.
- Ensure proper grounding and minimize the length of high-current traces.

FAQs

Q: Can the TPS61169 drive multiple LEDs in series?
A: Yes, the TPS61169 can drive multiple LEDs in series, provided the total forward voltage of the LEDs does not exceed the maximum output voltage (38V).

Q: What type of inductor should I use?
A: Use a shielded inductor with a current rating higher than the peak current of your application. Typical values range from 4.7 µH to 22 µH.

Q: How do I calculate the output voltage?
A: Use the formula ( V_{OUT} = V_{FB} \times (1 + R1/R2) ), where ( V_{FB} ) is 200 mV.

Q: Can I use the TPS61169 with a 3.3V microcontroller?
A: Yes, the EN pin can be controlled by a 3.3V logic signal to enable or disable the device.

By following this documentation, you can effectively integrate the Adafruit TPS61169 into your projects and troubleshoot common issues.