BT3L Module Datasheet

BT3L is an embedded Bluetooth LE module that Tuya has developed. It consists of a highly integrated Bluetooth chip (TLSR8250F512ET32) and several peripheral components, with an embedded Bluetooth network protocol stack and rich library functions.

Overview

BT3L contains a low-power 32-bit MCU, Bluetooth 5.0/2.4 GHz radio, 4 Mbits flash memory, 48 KB SRAM, and 9 reusable I/O interfaces.

Features

• Embedded low-power 32-bit MCU, which can also function as an application processor
• Clock rate: 48 MHz
• Working voltage: 1.8 V to 3.6 V (Under 1.8 V to 2.7 V, the module can start but the RF performance is not guaranteed. Under 2.8 V to 3.6 V, the module performance is normal.)
• Peripherals: nine pulse width modulation (PWM) interfaces
• Bluetooth RF features
  • Bluetooth LE 4.2/5.0
  • Up to 2 Mbit/s RF data rate
  • TX power: +10 dBm
  • RX sensitivity: –94.5 dBm at 1 Mbit/s
• Embedded advanced encryption standard (AES) hardware encryption
• Onboard PCB antenna with 2.5 dBi gain
• Working temperature: –40°C to +85°C

Applications

• Smart LED lights
• Smart households
• Smart low-power sensors

Module interfaces

Dimensions and footprint

The BT3L dimensions (H x W x L) are 3.3±0.15 mm x 16±0.35 mm x 24±0.35 mm. The PCB thickness is 0.8±0.1 mm. The BT3L pins are shown below:

Pin definition

The following table shows definitions of pins:

Pin No.	Symbol	I/O type	Function
1	RST	I/O	Hardware reset pin, which is active at a low level and is connected to pin RESET on the IC
2	ADC	AI	12-bit ADC, which is connected to pin TL_C4 on the IC
3	NC	NC	NC
4	TL_D7	I/O	Common I/O, which is connected to pin TL_D7 on the IC
5	TL_D2	I/O	Common I/O, which can be used as a PWM output of the LED drive and is connected to pin TL_D2 on the IC
6	TL_C3	I/O	Common I/O, which can be used as a PWM output of the LED drive and is connected to pin TL_C3 on the IC
7	TL_C2	I/O	Common I/O, which can be used as a PWM output of the LED drive and is connected to pin TL_C2 on the IC
8	VDD_BAT	P	Power supply pin (3.3 V)
9	GND	P	Power supply reference ground pin
10	TL_C0	I/O	GPIO, which is connected to pin TL_C0 on the IC
11	SWS	I	Programming pin, which is connected to pin TL_A7 on the IC
12	TL_A0	I/O	GPIO, which is connected to pin TL_A0 on the IC
13	TL_B4	I/O	Common I/O, which can be used as a PWM output of the LED drive and is connected to pin TL_B4 on the IC
14	TL_B5	I/O	Common I/O, which can be used as a PWM output of the LED drive and is connected to pin TL_B5 on the IC
15	TL_B7	I/O	Serial interface receiving pin (UART RX), which is connected to pin TL_B7 on the IC
16	TL_B1	I/O	Serial interface transmission pin (UART TX), which is connected to pin TL_B1on the IC

Note:

1. P indicates a power supply pin, I/O indicates an input/output pin, and AI indicates an analog input pin.
2. If you have any special requirements for light colours controlled by PWM outputs, contact Tuya business personnel.

Electrical parameters

Absolute electrical parameters

Parameter	Description	Minimum value	Maximum value	Unit
Ts	Storage temperature	-65	150	℃
VCC	Power supply voltage	-0.3	3.9	V
ESD voltage (human body model)	TAMB-25℃	-	2	KV
ESD voltage (machine model)	TAMB-25℃	-	0.5	KV

Electrical conditions

Parameter	Description	Minimum value	Typical value	Maximum value	Unit
Ta	Working temperature	-40	-	85	℃
VCC	Working voltage	2.8	3.3	3.6	V
VIL	I/O low-level input	VSS	-	VCC*0.3	V
VIH	I/O high-level input	VCC*0.7	-	VCC	V
VOL	I/O low-level output	VSS	-	VCC*0.1	V
VOH	I/O high-level output	VCC*0.9	-	VCC	V

Power consumption during work

Symbol	Condition	Maximum value (Typical value)	Unit
Itx	Constant transmission, 10 dBm output power	23	mA
Irx	Constant receiving	6.3	mA
IDC	Average value at mesh networking state	6.7	mA
IDC	Peak value at mesh networking state	24.9	mA
Ideepsleep1	Deep sleep mode 1 (16-KB RAM reserved)	1.2	μA
Ideepsleep2	Deep sleep mode 2 (No RAM reserved)	0.4	μA

RF features

Basic RF features

Parameter	Description
Frequency band	2.4GHz ISM band
Wireless standard	Bluetooth LE 4.2/5.0
Data transmission rate	1Mbps, 2Mbps
Antenna type	Onboard PCB antenna

RF output power

Parameter	Minimum value	Typical value	Maximum value	Unit
Average RF output power	-22	10	10.5	dBm
20 dB modulation signal bandwidth (1 Mbit/s)	-	2500	-	KHz
20 dB modulation signal bandwidth (2 Mbit/s)	-	1400	-	KHz

RF RX sensitivity

Parameter	Minimum value	Typical value	Maximum value	Unit
RX sensitivity 1Mbps	-	-94.5	-	dBm
RX sensitivity 2Mbps	-	-91	-	dBm
Frequency offset 1Mbps	-250	-	+300	KHz
Frequency offset 2Mbps	-300	-	+200	KHz
Co-channel interference suppression	-	-10	-	dB

Antenna

Antenna type

BT3L uses an onboard PCB antenna with a gain of 2.5 dBi.

Antenna interference reduction

To ensure optimal RF performance, it is recommended that the antenna be at least 15 mm away from other metal parts. If there are metal materials around the antenna, the wireless signals will be reduced greatly, thereby deteriorating the RF performance. So when designing a finished product, you should leave enough space for the antenna.

Packaging information and production instructions

Mechanical dimensions and outline of the back pad

Recommended PCB footprint

Note: The default dimensional tolerance is ±0.35 mm, and the key dimensional tolerance is ±0.1 mm. If you have any special requirements, clearly specify them in the datasheet after communication. The area indicated as keep-out in the diagram above does not require tinning and should not have any traces routed through it.

Production instructions

1. For the modules that can be packaged with the SMT or in the in-line way, you can select either of them according to the PCB design solutions of customers. If a PCB is designed to be SMT-packaged, package the module with the SMT. If a PCB is designed to be in-line-packaged, package the module in an in-line way. After being unpacked, the module must be soldered within 24 hours. Otherwise, it needs to be put into the drying cupboard where the relative humidity is not greater than 10%; or it needs to be packaged again under vacuum and the exposure time needs to be recorded (the total exposure time cannot exceed 168 hours).

   • (SMT process) SMT devices:
     • Mounter
     • SPI
     • Reflow soldering machine
     • Thermal profiler
     • Automated optical inspection (AOI) equipment
   • (Wave soldering process) Wave soldering devices:
     • Wave soldering equipment
     • Wave soldering fixture
     • Constant-temperature soldering iron
     • Tin bar, tin wire, and flux
     • Thermal profiler
   • Baking devices:
     • Cabinet oven
     • Anti-electrostatic and heat-resistant trays
     • Anti-electrostatic and heat-resistant gloves

2. Storage conditions for a delivered module:

   • The moisture-proof bag must be placed in an environment where the temperature is below 40°C and the relative humidity is lower than 90%.

   • The shelf life of a dry-packaged product is 12 months from the date when the product is packaged and sealed.

   • There is a humidity indicator card (HIC) in the packaging bag.

     

3. The module needs to be baked in the following cases:

   • The packaging bag is damaged before unpacking.
   • There is no humidity indicator card (HIC) in the packaging bag.
   • After unpacking, circles of 10% and above on the HIC become pink.
   • The total exposure time has lasted for over 168 hours since unpacking.
   • More than 12 months have passed since the sealing of the bag.

4. Baking settings:

   • Temperature: 40°C and ≤ 5% RH for reel package and 125°C and ≤5% RH for tray package (please use the heat-resistant tray rather than plastic container)
   • Time: 168 hours for reel package and 12 hours for tray package
   • Alarm temperature: 50°C for reel package and 135°C for tray package
   • Production-ready temperature after natural cooling: < 36°C
   • Re-baking situation: If a module remains unused for over 168 hours after being baked, it needs to be baked again.
   • If a batch of modules is not baked within 168 hours, do not use the reflow soldering or wave soldering to solder them. Because these modules are Level-3 moisture-sensitive devices, they are very likely to get damp when exposed beyond the allowable time. In this case, if they are soldered at high temperatures, it may result in device failure or poor soldering.

5. In the whole production process, take electrostatic discharge (ESD) protective measures.

6. To guarantee the passing rate, it is recommended that you use the SPI and AOI to monitor the quality of solder paste printing and mounting.

Recommended oven temperature curve

Select a proper soldering manner according to the process. For the SMT process, please refer to the recommended oven temperature curve of reflow soldering. For the wave soldering process, please refer to the recommended oven temperature curve of wave soldering. There are some differences between the set temperatures and the actual temperatures. All the temperatures shown in this module datasheet are obtained through actual measurements.

Manner 1: SMT process (Recommended oven temperature curve of reflow soldering)

Set oven temperatures according to the following curve.

• A: Temperature axis

• B: Time axis

• C: Liquidus temperature: 217 to 220°C

• D: Ramp-up slope: 1 to 3°C/s

• E: Duration of constant temperature: 60 to 120s; the range of constant temperature: 150 to 200°C

• F: Duration above the liquidus: 50 to 70s

• G: Peak temperature: 235 to 245°C

• H: Ramp-down slope: 1 to 4°C/s

  Note: The above curve is just an example of the solder paste SAC305. For more details about other solder pastes, please refer to Recommended oven temperature curve in the solder paste specifications.

Manner 2: Wave soldering process (Oven temperature curve of wave soldering)

Set oven temperatures according to the following temperature curve of wave soldering. The peak temperature is 260°C±5°C.

Suggestions on oven temperature curve of wave soldering		Suggestions on manual soldering temperature
Preheat temperature	80 to 130 °C	Soldering temperature	360±20°C
Preheat time	75 to 100s	Soldering time	＜3s/point
Peak contact time	3 to 5s	NA	NA
Temperature of tin cylinder	260±5°C	NA	NA
Ramp-up slope	≤2°C/s	NA	NA
Ramp-down slope	≤6°C/s	NA	NA

Storage conditions

MOQ and packaging information

Product number	MOQ (pcs)	Packing method	The number of modules per reel	The number of reels per carton
BT3L	3600	Tape reel packing	900	4

Appendix: Statement

FCC Caution: Any changes or modifications not expressly approved by the party responsible for compliance could void the user’s authority to operate this device.

This device complies with Part 15 of the FCC Rules. Operation is subject to the following two conditions: (1) This device may not cause harmful interference, and (2) this device must accept any interference received, including interference that may cause undesired operation.

Note: This device has been tested and found to comply with the limits for a Class B digital device, according to part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This device generates, uses, and can radiate radio frequency energy and, if not installed and used following the instructions, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation.

If this device does cause harmful interference to radio or television reception, which can be determined by turning the device off and on, the user is encouraged to try to correct the interference by one or more of the following measures:

• Reorient or relocate the receiving antenna.
• Increase the separation between the device and receiver.
• Connect the device to an outlet on a circuit different from that to which the receiver is connected.
• Consult the dealer or an experienced radio/TV technician for help.

Radiation Exposure Statement

This device complies with FCC radiation exposure limits set forth for an uncontrolled rolled environment. This device should be installed and operated with a minimum distance of 20cm between the radiator and your body.

Important Note

This radio module must not be installed to co-locate and operate simultaneously with other radios in the host system except following FCC multi-transmitter product procedures. Additional testing and device authorization may be required to operate simultaneously with other radios.

The availability of some specific channels and/or operational frequency bands are country dependent and are firmware programmed at the factory to match the intended destination. The firmware setting is not accessible by the end-user.

The host product manufacturer is responsible for compliance with any other FCC rules that apply to the host not covered by the modular transmitter grant of certification. The final host product still requires Part 15 Subpart B compliance testing with the modular transmitter installed.

The end-user manual shall include all required regulatory information/warnings as shown in this manual, including “This product must be installed and operated with a minimum distance of 20 cm between the radiator and user body”.

This device has got an FCC ID: 2ANDL-BT3L. The end product must be labeled in a visible area with the following: “Contains Transmitter Module FCC ID: 2ANDL-BT3L”.

This device is intended only for OEM integrators under the following conditions:

The antenna must be installed such that 20cm is maintained between the antenna and users, and the transmitter module may not be co-located with any other transmitter or antenna.

As long as the 2 conditions above are met, further transmitter tests will not be required. However, the OEM integrator is still responsible for testing their end-product for any additional compliance requirements required with this module installed.

Declaration of Conformity European Notice

Hereby, Hangzhou Tuya Information Technology Co., Ltd declares that this module product is in compliance with essential requirements and other relevant provisions of Directive 2014/53/EU,2011/65/EU. A copy of the Declaration of conformity can be found at https://www.tuya.com.

This product must not be disposed of as normal household waste, in accordance with the EU directive for waste electrical and electronic equipment (WEEE-2012/19/EU). Instead, it should be disposed of by returning it to the point of sale, or a municipal recycling collection point.

The device could be used with a separation distance of 20cm to the human body.