Other Issues of Lighting

What do I do if a bulb flashes once when I turn it off?

1. Use an oscilloscope to view the VCC waves and output I/O pins on the module. Check whether the 3.3 V power supply is restarted after the bulb is turned off, which causes a module restart.

2. If the CCT firmware is used and the warm white light flashes once after the bulb is turned off, test the warm white bead's current and module's output CCT wave. Check whether the output electrolytic capacitor discharges remaining power from the warm white bead because the CCT signals are dropped to 0 V at an earlier time. Reduce the dummy load resistance on the output electrolytic capacitor or reduce the output electrolytic capacitance.

How many color types does RGB bulb support?

Theoretically, 255*255*255=16.7M types.

What lamps does Tuya provide?

Tuya lamps include sphere lamps, panel (ceiling) lamps, downlights, light strips, table lamps, light strings, outdoor lamps, and dimmable lamps.

Why does the module in an LED power supply have weak signals?

Check whether the module's antenna is close to magnetic components. If yes, modify the PCB tracing.

Why can't I control multiple lamps in a group simultaneously?

To control multiple lamps in a group simultaneously, the lamps must have the same embedded module firmware version and same panel DPs.

Why are the colors in color light mode inaccurate?

The colors of lamps in color light mode vary with the beads selected by customers. You need to perform gamma calibration based on the bead or light adjustment chip.

What are the light colors corresponding to different color temperature values?

Color temperatures produce warm white from 2700 K to 4000 K, natural white from 4000 K to 5700 K, pure white from 6000 K to 7000 K, and cool white above 8000 K. Color temperatures are only used to describe the white light provided by a light bulb and are measured in degrees of Kelvin (K). Wavelengths are used to describe color lights.

How do I add 1-channel physical switch for lamps with cold/warm control light adjustment?

The leftmost three GPIO ports on Tuya's lamp strip firmware and cold/warm CCT light strip can be used to connect to relays and act as physical switches. If you use the MCU solution, you can use the rightmost U0RXD and U0TXD ports.

What can I do if my lamp is off when being powered on?

Check whether parameters such as I/O ports and effective level are configured correctly. Use a demo board to program the problematic firmware to check whether corresponding I/O ports have PWM output. If yes, find other causes. If no, contact the firmware developer to rectify the fault.

What can I do if my lamp does not enter the network pairing mode (quick blinking state)?

1. Power cycle your lamp three times and wait for about 5s to 6s because the module requires up to 6s to enter the network pairing mode.

2. During the three power cyclings, retain a long power-off time and ensure that the power-on time does not exceed 5s.

3. Use an oscilloscope to view waves of the VCC and I/O pins on the module. Check whether the VCC pin has power cycled three times and whether the VCC remains stable after the module is powered on.

4. During product design, use a resistor of about 300 R as the 3.3 V dummy load.

5. Use a 3.3 V DC source to power the module. Use an oscilloscope to view the module's PWM output signals. Power cycle the 3.3 V power supply three times and check whether the connected I/O pin on the module generates quick blinking waves.

6. View the network pairing mode and number of power cyclings configured on the Tuya Smart platform's Hardware Debug page of the lamp.

This is because the I2C signals are interfered. Connect 4.7-kiloohm resistors to the CLK and SDA pins, and pull up the resistors to ensure that the power voltage is 3.3 V. Connect a 22 pF capacitor between CLK and GND.

Some lamps are steady on while some others flash fast after power-on. Why?

Some lamps provide the low power feature. They enter the low power mode and are steady on upon first power-on after factory delivery. They enter the network pairing mode after three power cyclings. If they are not paired to a network in more than 10s, they will enter the low power mode and be steady on after power cycling again. Some lamps do not provide the low power feature and they flash quickly by default, until being paired to a network.How helpful was this page?Excellent

Does a lamp with general firmware retain its previous state or is steady on after power cycling?

By default, all lamps are steady on after power cycling.

How do the two PWM pins on a module adjust the light brightness and color temperature?

GPIO5 and GPIO13 are used for cold light and warm light control, respectively. The PWM pins' duty cycle can be adjusted for brightness control.

Why does my lamp have stripe flickering in my mobile phone's camera?

It flickers because the module's driver frequency is low. To solve the problem, increase the module's PWM output frequency to 16 kHz or higher, if the LED driver supports such a high frequency. Alternatively, use a constant-current solution. Adjust the brightness to the lowest level and use a mobile phone camera to check whether your lamp still flickers.

What are the precautions for using a module (with an antenna) in a downlight or spotlight?

When using a module in a lamp with a metal cover, for example, a downlight, spotlight, or outdoor lamp, consider the antenna RF design and use an external antenna if needed. To use the module in a driver, keep the module away from the components such as the transformer and inductor.

What are the consequences if there is no dropping resistor in the peripheral schematic diagram of a downlight?

If there is no dropping resistor, the module's I/O pins will be burned out.

What is the power of sphere lamps?

Typically, 6W, 8W and 10W.

Why can't I control my lamp's light color properly?

Tuya provides the PWM and I2C solutions with different firmware to control RGB lamps' light colors. If color control is abnormal, the module firmware may mismatch your hardware design.

Where do I install an antenna in a sphere lamp?

To use a module in a sphere lamp, ensure that the module's antenna is out of the opening groove of the alumina substrate and that the onboard antenna is higher than the alumina substrate. When the light source is not affected and there are no shadows, position the antenna out of the lamp cup's shielding environment as much as possible.

What can I do if a lamp enters the network pairing state but fails network pairing?

1. Enable the router's 2.4 GHz Wi-Fi and disable the 5 GHz Wi-Fi. If both 2.4 GHz and 5 GHz are enabled, network pairing will fail.

2. Ensure that the router's network speed is normal and that the router does not connect to multiple devices. Use a 4G mobile phone with a fast network speed as a router, enable a personal hotspot for the lamp, and check whether the network pairing is successful.

3. Check whether the Wi-Fi password you have entered in the app is correct. The password cannot start or end with a space.

4. Check whether the PID of the lamp is deleted from the Tuya Smart platform. If yes, network pairing will fail because the cloud does not have the module information corresponding to the PID.

5. Use an oscilloscope to check the module's VCC wave. If VCC drops below 3.3 V during network pairing, the network pairing may fail.

6. Make the lamp blink slowly and use the AP mode in the app to pair the lamp.

A 1-kiloohm dropping resistor is recommended.

How do I select a power drive for a sphere lamp?

1. If you use a non-certified power supply, the non-isolated SY50282 is recommended.

2. If you use a certified power supply, AP3776BM and APR34309C are recommended to support high power.

3. If you require USB ports, the Silergy SY50135 with an embedded MOSFET is recommended.

4. If you use a low-cost certified product, SY50101 with an embedded MOSFET is recommended.

Why can't I adjust the color temperature for my lamp?

Tuya provides the CW and CCT solutions with different firmware to adjust lamps' color temperatures. If you cannot adjust a lamp's color temperature, the module firmware may mismatch your hardware design.

Is there a plug-and-play solution for light modulators?

No. MCU docking is required.

What can I do to prevent some lamps from flashing at low brightness?

Discuss with your hardware provider to check whether the driver solution can be optimized, for example, whether the issue is caused by frequency mismatching. If this issue cannot be solved through hardware optimization, adjust the frequency or the minimum brightness by using the software.

What is the maximum PWM frequency in the SIG mesh lighting solution?

Currently, up to 20 kHz is supported. We do not recommend that you set a high frequency because it may affect the PWM stability.

Are buttons available for SIG mesh lamps?

No. This feature will come soon.

What is the PWM frequency range?

100 Hz to 20000 Hz

Do SIG mesh lamps comply only with the standard SIG protocol specifications?

No. SIG mesh lamps also use Tuya's private protocols such as the scene protocol.

Can I edit the app panel for a plug-and-play lighting product?

Yes. On the App UI Design page, select a custom panel template and define the panel elements.

Can I use two buttons to control a plug-and-play lamp?

No. You can set only one button for network pairing and switch-on or switch-off for a plug-and-play lamp.

What is the minimum PWM frequency of a plug-and-play lighting product?

The minimum PWM frequency is 100 Hz.

Is it possible to adjust the color temperature of a cold/warm bi-colored light with the wall switch?

Yes, but the network configuration mode of the firmware needs to be redefined to prevent getting into the network configuration through switching multiple times.

What is the output PWM frequency of a Tuya plug-and-play lighting product?

The frequency can be set to 20 kHz at most, but a high frequency will lead to PWM instability and therefore is not recommended.

Does Tuya provide constant-current lighting products?

Yes. Use the I2C 2135E or the PWM for constant-current conversion.

Does Tuya provide plug-and-play I2C lighting product solutions?

Yes. Tuya provides RGB lamps with the SM726 chip and RGBCW lamps with the SM2135E chip.

My lamp is in the slowly flash mode and cannot be switched to the fast flash mode. Why?

A possible cause is that your module has not been authorized. Connect the module and display the related information to check whether the module is authorized. (If the module is unauthorized, log information such as that shown in the following figure is displayed). If yes, authorize the module. Otherwise, troubleshoot the issue. ESP8266 or ESP8285: Realtk: If the module log contains the 903 error, the firmware is not authorized.

When will Tuya plug-and-play RGBW to RGBCW lamps be launched?

Currently, RGBW to RGBCW lamps are not supported.

Why does the input power of a lamp remain unchanged after I have adjusted the brightness bar in the app?

The lamp may use a constant-voltage current limit and MOSFET transistor solution with high output voltage (Vout). After the current limit is reached and you adjust the brightness to a larger value, the output current will remain unchanged. When adjusting brightness in the app, check whether the module's output PWM wave changes properly. Then, check whether the brightness adjustment circuit is abnormal or has reached the current upper limit when it receives PWM signals.

Does Tuya provide plug-and-play light strips with IR remote controls?

No. To develop such products, use custom firmware.

What is a single indicator solution?

The indicator flashes, indicating the network pairing mode. In other cases, the indicator indicates the relay status.

Why does my bulb automatically reset the next day after network pairing?

If a module is restarted repeatedly, it will start network pairing again. If the voltage is unstable, the module may also be reset. If the problem often occurs, use a constant-voltage source to perform an aging test on the module's power supply.

Why is there no connection in the peripheral circuit diagram of the bulb in the development free solution?

In the upper part of our reference circuit diagram, the network label is not connected with other places, and the RGB below is not connected in the air.

For lighting products, how to select modules?

The selection of the module mainly based on the application scenario. First of all, considering the temperature, the temperature of Tuya module includes 85 degrees and 105 degrees. Generally, 105 degrees ones will be selected for bubble bulb, and 85 degrees ones for external drive. Secondly, considering the processing method and volume, the module has the processing method of vertical insertion and flat sticking. Besides, regarding the processing method of the antenna, the Wi-Fi module includes an on-board antenna, an external IPEX antenna, a spring antenna, and so on. It is necessary to choose the module that fits the product structure.

Can I set more volume levels for color changes of a music lamp?

A music lamp analyzes the audio rhythm instead of the volume to change the light colors. For example, if a song has a good beat, the light colors change frequently. As Tuya Wi-Fi lamps control and change the light colors through a network, a latency is involved. A fine light color switching requirement cannot be met.

Does the lighting plug-and-play solution support button control?

When creating a Wi-Fi lighting plug-and-play solution, you can configure a button for network pairing or switching the light on or off.

Why does my lamp flicker frequently at the highest brightness?

An AC/DC circuit must maintain a constant voltage. When the power supply works in constant current mode, the working current of the Wi-Fi module fluctuates greatly, which affects the power supply's working mechanism. As a result, the LED light's main power supply fluctuates, resulting in light flickers.

What do I do if my lamp flashes once upon each power-on?

1. Connect a 3-kiloohm pull-down resistor to the output I/O pin on the module, which is pulled up slightly when the module is powered on.

2. Use an oscilloscope to check the module's I/O pin waves. Check whether flashing is occurring because the module is generating a high level or the power supply is faulty.

3. Check whether an electrolytic capacitor is connected to the LED bead in series and then to the GND pin. If yes, when the electrolytic capacitor is powered on and charged, it will generate a weak transient current, resulting in a slight LED light flash.

What is the button on a plug-and-play RGBCW lamp used for?

The button is used for turning on or off the lamp and pairing the lamp with the app. To enable more functions for the button, customize the firmware or use the MCU solution.

Why does my LED light flicker?

The possible causes are as follows:

1. The PWM signal cable is too long.

2. The LED light is close to a magnetic component. If either of the preceding problem occurs, modify PCB cabling

What is the logic of indicator multiplexing on a lamp?

The same indicator is used as the Wi-Fi indicator and the power indicator. During network pairing, the indicator shows the network status preferentially. When the light is connected to or disconnected from the network or in low power mode, the indicator shows the relay status preferentially.

How are PWM-RGB and I2C-RGB different for controlling an RGB lamp?

PWM-RGB indicates that three I/O pins on the module separately generate one channel of PWM signals to control the current and on/off of the RGB lamp. I2C-RGB indicates that two I/O pins on the module separately transmit SCL clock signals and SDA data signals to the LED control ICs to control the brightness and color temperature of the RGB lamp. The ICs use different protocols. The I2C SoC solutions on the Tuya Smart platform support only SM726EB and SM2135. If you select another control IC, use custom firmware.

How do I choose a lighting product module power supply mode?

  • AC-DC constant voltage output power supply: A module's normal working voltage range is 3.0 V to 3.6 V. If the output voltage is higher than 3.3 V, consider the output voltage ripple and output power in addition to the power to the module to prevent insufficient power supply to the module due to undervoltage output. The power supply system must ensure a stable power supply voltage under the maximum output power. If the output voltage is the module's power supply voltage or 3.3 V, set the output voltage midpoint value to 3.3 V to have a ripple voltage of less than 100 mV and an average Wi-Fi module current of about 80 mA. The AC-DC power supply system must generate 200 mA current on average. The peak value of the dynamic output current of the power supply system must reach 450 mA, and the voltage drop cannot exceed 2.8 V. The 3.3 V Wi-Fi module's power supply pin is connected to a 0.1 μF ceramic capacitor to reduce interference. To power a 3.3 V Bluetooth or Zigbee module, the DC-DC power supply system must have a ripple voltage of less than 100 mV and be able to generate 50 mA current on average. When the dynamic output current is 100 mA, the output voltage drop will not exceed 2.8 V. In low standby power application scenarios, select the low standby power AC-DC drive chip and a module with a low standby current. Use a diode and capacitor to isolate the AC-DC power supply circuit from the main power to prevent the working module from affecting the main power, especially the linear constant-current drive power source, so that flickering light will not occur.

  • DC-DC constant-voltage output power supply: When a module embedded with a DC-DC voltage reduction circuit is powered by DC voltage, the DC voltage cannot exceed 40 V. When the DC voltage exceeds 3.3 V, use a voltage reduction chip to reduce the voltage to 3.3 V. A switch-type voltage reduction control chip is recommended. To power a 3.3 V Wi-Fi module, the DC-DC power supply system must have a ripple voltage of less than 100 mV and be able to generate 200 mA current. When the dynamic output current is 450 mA, the output voltage drop does not exceed 2.8 V. The 3.3 V Wi-Fi module's power supply pin is connected to a 0.1 μF ceramic capacitor to reduce interference. To power a 3.3 V Bluetooth or Zigbee module, the DC-DC power supply system must have a ripple voltage of less than 100 mV and be able to generate 50 mA current on average. When the dynamic output current is 100 mA, the output voltage drop will not exceed 2.8 V.

Can I place an 85°C module in a sphere lamp?

No. A sphere lamp has a high temperature and requires a 105°C module.

What is an RGB lamp?

An RGB lamp has adjustable light colors. The red, green, and blue (RGB) color model is an industry standard color model in which the red light, green light, and blue light overlay in various ways to reproduce a broad array of colors. The model can reproduce almost all colors that human eye can perceive. It is one of the most widely used color models. Each of the red, green, and blue color channels has values of 0 to 255, indicating gray scale levels. An RGB system can have 16,777,216 (2563) possible colors. The RGB system is also called RGB24 (24-bit mode).

What is the default color of an RGBCW lamp during network pairing?

The default color of an RGBCW lamp is cold white during network pairing. You can change the color when creating the lamp on the Tuya Smart platform.

What lamps are suitable for atmosphere lighting?

Auxiliary lighting (ambient lighting) lamps are used for decoration instead of main lighting. These lamps are often used as decorations for Christmas in North America. You are advised to use light strips, light strings, and outdoor lamps. It is recommended that you consider the Bluetooth solution for outdoor lamps.

What lamps are suitable for Tuya home lighting?

You are advised to use Tuya home lighting products for ceiling lamps, panel lamps, and downlights. Tuya home lighting products have the following features:

1. Use similar driver solutions.

2. Support diversified appearance design, and each has higher value than a sphere lamp.

3. Support white light adjustment, and cold and warm light color change.

What are Tuya's lighting product solutions?

Tuya provides extensive lighting product solutions applicable to different phases, including module solutions, semi-finished PCBA solutions, and finished product solutions. Tuya's lighting product types include the A60 bulb, A70 bulb, BR30 bulb, PAR bulb, GU10 bulb, filament lamp, light strip, downlight, spotlight, ceiling lamp, panel lamp, light string, fluorescent tube, table lamp, and night lamp.

What is a CW lamp?

A cold and warm white (CW) lamp produces white light with adjustable brightness and color temperatures.

What is a C lamp?

A cold-white (C) lamp produces white light with adjustable brightness.

What is an RGBCW lamp?

RGBCW combines the initials of red, green, blue, cold white, and warm white. An RGBCW lamp has adjustable light colors, brightness, and color temperatures.

What are the components of a sphere lamp?

A typical sphere lamp consists of a base, drive, body, panel, LED, and cover.

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