WRD3L Module Datasheet

WRD3L is a low-power embedded Wi-Fi module that Tuya has developed. It consists of a highly integrated wireless RF chip (RDA5981BM), a few peripherals, an embedded Wi-Fi network protocol stack, and varied library functions.

Product overview

WRD3L has an embedded low-power ARM-CM4 MCU, 2-MB flash memory, 448-KB static random-access memory (SRAM), and rich peripherals.

WRD3L is an RTOS platform that integrates all function libraries of the Wi-Fi MAC and TCP/IP protocols. You can develop embedded Wi-Fi products as required.

Features

• Embedded low-power 32-bit CPU, which can also function as an application processor
• The clock rate: 160 MHz
• Working voltage: 3.0 to 3.6 V
• Peripherals: 9 GPIOs, 1 universal asynchronous receiver/transmitter (UART), and 1 analog-to-digital converter (ADC)
• Wi-Fi connectivity
  • 802.11 b/g/n
  • Channels 1 to 14 at 2.4 GHz
  • Support WPA/WPA 2/WEP/TKIP security modes
  • Up to +17 dBm output power in 802.11b mode
  • Support STA/AP/STA+AP working mode
  • Support SmartConfig and AP network configuration manners for Android and iOS devices
  • Onboard PCB antenna with a gain of 1.0 dBi
  • Working temperature: -20 to 105℃

Applications

• Intelligent building
• Smart household and home appliances
• Smart socket and light
• Industrial wireless control
• Baby monitor
• Network camera
• Intelligent bus

Change history

Date	Updated content	Version after update
08/20/2019	This is the first release.	V1.0.0
09/16/2019	The document upgrades.	V2.0.0

Module interfaces

Dimensions and footprint

WRD3L has two rows of pins with a 2 mm pin spacing.
The WRD3L dimensions are 16±0.35 mm (W)×24±0.35 mm (L) ×3.0±0.15 mm (H).

Pin definition

Pin Number	Symbol	I/O Type	Function
1	NRST	I/O	Hardware reset pin, active low
2	ADC	AI	ADC
3	NC	I	Empty pin, which has no internal connection
4	GPIO0	I/O	GPIO_0, which correspond to GPIO 0 (Pin 36) of IC
5	GPIO23	I/O	GPIO_23/Standard PWM interface, which corresponds to GPIO 23 (Pin 33) of IC
6	GPIO24	I/O	GPIO_24/Standard PWM interface, which corresponds to GPIO 24 (Pin 32) of IC
7	GPIO25	I/O	GPIO_25/Standard PWM interface, which corresponds to GPIO 25 (Pin 31) of IC
8	VCC	P	Power supply pin (3.3V)
9	GND	P	Power supply reference ground
10	GPIO1	O	GPIO_1, which corresponds to GPIO 0 (Pin 21) of IC
11	GPIO2	O	UART2_TXD (used to display the internal information of the module), which corresponds to GPIO 2 (Pin 22) of IC
12	GPIO5	I/O	GPIO_5, which corresponds to GPIO 5 (Pin 14) of IC
13	GPIO22	I/O	GPIO_22/Standard PWM interface, which corresponds to GPIO 22 (Pin 34) of IC
14	GPIO3	I/O	GPIO_3/Standard PWM interface, which corresponds to GPIO 3 (Pin 23) of IC
15	RX	I/O	UART_RX, which corresponds to GPIO 27 (Pin 16) of IC
16	TX	O	UART_TX, which corresponds to GPIO 26 (Pin 24) of IC

Note: P indicates power supply pins and I/O indicates input/output pins.

Definitions on test points

Pin Number	Symbol	I/O Type	Function
-	TEST	I/O	Be used for production tests of the module

Note: Test pins are not recommended.

Electrical parameters

Absolute electrical parameters

Parameter	Description	Minimum value	Maximum Value	Unit
Ts	Storage temperature	-40	105	℃
VBAT	Power supply voltage	3.0	3.6	V
Static electricity discharge voltage (human body model)	TAMB-25℃	-	2	KV
Static electricity discharge voltage (machine model)	TAMB-25℃	-	0.5	KV

Normal Working Conditions

Parameter	Description	Minimum value	Typical Value	Maximum Value	Unit
Ta	Working temperature	-20	-	105	℃
VBAT	Power supply voltage	3.0	3.3	3.6	V
VIL	IO low-level input	-0.3	-	VCC*0.3	V
VIH	IO high-level input	VCC*0.75	-	VCC	V
VOL	IO low-level output	-	-	VCC*0.1	V
VOH	IO high-level output	VCC*0.8	-	VCC	V
Imax	IO drive current	-	-	12	mA

TX and RX power consumption

Working Status	Mode	Rate	Transmit Power/Receive	Average Value	Peak Value (Typical Value))	Unit
Transmit	11 b	11Mbps	+17 dBm	210	354	mA
Transmit	11 g	54Mbps	+14.5 dBm	180	300	mA
Transmit	11 n	MCS 7	+13.5 dBm	170	290	mA
Receive	11b	11Mbps	Constantly receive	80	100	mA
Receive	11g	54Mbps	Constantly receive	80	100	mA
Receive	11n	MCS 7	Constantly receive	80	100	mA

Working current

Working Mode	Working Status, Ta = 25°C	Average Value	Maximum Value (Typical Value)	Unit
Quick connection network state	The module is in the fast network connection state and the Wi-Fi indicator always flashes	70	312	mA
Hotspot network configuration state	The module is in the hotspot network configuration state and the Wi-Fi indicator flashes slowly	80	345	mA
Network connection operation state	The module is connected to the network and the Wi-Fi indicator is always on	70	210	mA

RF parameters

Basic RF features

Parameter	Description
Working frequency	2.412 to 2.484 GHz
Wi-Fi standard	IEEE 802.11 b/g/n (channels 1 to 14)
Data transmission rate	11b: 1, 2, 5.5, 11 (Mbps); 11g: 6, 9, 12, 18, 24, 36, 48, 54 (Mbps); 11n: HT20 MCS 0 to 7
Antenna type	PCB antenna with a gain of 1.0 dBi

TX performance

TX performance

Parameter	Minimum Value	Typical Value	Maximum Value	Unit
Average RF output power, 802.11b CCK Mode 11 M	-	17	-	dBm
Average RF output power, 802.11g OFDM Mode 54 M	-	14	-	dBm
Average RF output power, 802.11n OFDM Mode MCS7	-	13	-	dBm
Frequency error	-20	-	20	ppm

RX performance

RX sensitivity

Parameter	Minimum Value	Typical Value	Maximum Value	Unit
PER<8%, RX sensitivity, 802.11b DSSS Mode 11 M	-	-90	-	dBm
PER<10%, RX sensitivity, 802.11g OFDM Mode 54 M	-	-73	-	dBm
PER<10%, RX sensitivity, 802.11n OFDM Mode MCS7	-	-70	-	dBm

Antenna

Antenna type

WRD3L uses only an onboard PCB antenna.

Antenna interference reduction

To ensure optimal Wi-Fi performance when the Wi-Fi module uses an onboard PCB antenna, it is recommended that the antenna be at least 15 mm away from other metal parts.
To ensure the antenna performance, the PCB should not be routed or clad with copper in the antenna area.
The main points of the layout:

• Make sure that there is no substrate medium directly below or above the printed antenna.
• Make sure that the area around the printed antenna is far away from the metal copper skin, so as to ensure the radiation effect of the antenna to the greatest extent.
  

Packaging information and production instructions

Mechanical dimensions

Side view

The schematic diagram of packaging

PCB layout

Production instructions

1. Tuya’s stamp hole package module must be mounted by the SMT machine within 24 hours after unpacking and programming of the firmware. Otherwise, it must be packaged again under a vacuum. The module must be baked before mounting.

   • SMT equipment
     • Reflow soldering machine
     • Automated optical inspection (AOI) equipment
     • Nozzle with a 6 mm to 8 mm diameter
   • Baking equipment
     • Cabinet oven
     • Anti-static heat-resistant trays
     • Anti-static heat-resistant gloves

2. Storage conditions for a delivered module are as follows:

   • The moisture-proof bag must be placed in an environment where the temperature is below 30°C and the relative humidity is lower than 70%.
   • The shelf life of a dry-packaged product is 6 months from the date when the product is packaged and sealed.
   • The package contains a humidity indicator card (HIC).
     

3. Bake a module based on HIC status as follows when you unpack the module package:

   • If the 30%, 40%, and 50% circles are blue, bake the module for 2 consecutive hours.
   • If the 30% circle is pink, bake the module for 4 consecutive hours.
   • If the 30% and 40% circles are pink, bake the module for 6 consecutive hours.
   • If the 30%, 40%, and 50% circles are pink, bake the module for 12 consecutive hours.

4. Baking settings:

   • Baking temperature: 125±5°C
   • Alarm temperature: 130°C
   • SMT ready temperature after natural cooling: < 36°C
   • The number of drying times: 1
   • Rebaking condition: The module is not soldered within 12 hours after baking

5. Do not use SMT to process modules that have been unpacked for more than 3 months, because electroless nickel/immersion gold (ENIG) is used for PCBs and they are seriously oxidized after more than 3 months. SMT is very likely to cause pseudo and missing soldering. Tuya is not liable for such problems and consequences.

6. Before SMT, take electrostatic discharge (ESD) protective measures.

7. To reduce the reflow defect rate, draw 10% of the products for visual inspection and AOI before the first mounting to determine proper methods for controlling the oven temperature and attaching and placing components. Draw 5 to 10 modules from subsequent batches each hour for visual inspection and AOI.

Recommended oven temperature curve

Perform SMT based on the following reflow oven temperature curve. The highest temperature is 245°C. The reflow temperature curve is shown below:

Storage conditions

MOQ and packaging information

Product Number	MOQ（pcs）	Shipping packaging method	The number of modules per reel	The number of reels per carton
WRD3L	4000	Tape reel	1000	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 into 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 operating 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-WRD3L. The end product must be labeled in a visible area with the following: “Contains Transmitter Module FCC ID: 2ANDL-WRD3L”.

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 to a municipal recycling collection point.

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