Data Sheet
Table Of Contents
- 1 Overview and Key Features
- 1.2 Application Areas
- Features and Benefits
- 2 Specifications
- 3 Hardware Specifications
- 3.1 Block Diagram and Pin-out
- 3.2 Pin Definitions
- 3.3 Electrical Specifications
- 4 Functional Description
- 4.1 Power Management (includes brown-out and power on reset)
- 4.2 Clocks and Timers
- 4.3 RF
- 4.4 UART Interface
- 4.5 SPI Bus
- 4.6 I2C Interface
- 4.7 General Purpose I/O, ADC and PWM/FREQ
- 4.8 nRESET Pin
- 4.9 nAutoRUN Pin
- 4.10 RM1xx VSP Service and Modes
- 4.11 Two-Wire SWD Programming/Debug Interface
- 4.12 RM1xx on-board chip antenna characteristics
- 5 Hardware Integration Suggestions
- 6 Mechanical Details
- 7 Application Note for Surface Mount Modules
- 8 FCC and IC Regulatory Statements
- 9 CE Regulatory
- 10 EU Declarations of Conformity
- 11 Ordering Information
- 12 Bluetooth SIG Qualification
RM1xx LoRa/BLE Modules
Datasheet
https://connectivity.lairdtech.com/wireless-
modules/lorawan-solutions
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nRESET pin (active low)
Hardware reset. Wire out to push button or drive by host.
By default module is out of reset when power applied to VCC pin.
5.2 PCB Layout on Host PCB – General
Checklist (for PCB):
MUST locate RM1xx module close to the edge of PCB (mandatory for RM1xx for on-board chip antenna to radiate
properly).
Use solid GND plane on inner layer (for best EMC and RF performance).
All module GND pins MUST be connected to host PCB GND.
Place GND vias close to module GND pads as possible.
Unused PCB area on the top layer can be flooded with copper but place GND vias regularly to connect copper flood to
inner GND plane. If GND flood copper exists on the top PCB layer (under of the RM1xx module), then connect with
GND vias to inner GND plane and ensure that it is covered with solder mask.
Route traces to avoid noise being picked up on VCC supply and AIN (analogue) and SIO (digital) traces.
Ensure no exposed copper beneath the module (refer to land pattern of RM1xx development board).
5.2.1 BLE Chip Antenna Keep-out on Host PCB
Ensure there is no copper in the antenna keep-out area on any layers of the host PCB. Keep all mounting hardware
and metal clear of the area to allow proper antenna radiation.
For best antenna performance, place the RM1xx module on the edge of the host PCB, preferably in the corner with
the antenna facing the corner.
The RM1xx development board has the RM1xx module on the edge of the board (not in the corner). The antenna
keep-out area is defined by the RM1xx development board which was used for module development (and antenna
performance evaluation) is shown in Figure 9, where the antenna keep-out area is composed of PCB dielectric (no
copper) sitting under the RM1xx antenna.
A different host PCB thickness dielectric will have small effect on antenna.
The antenna-keep-out defined in Host PCB Land Pattern and Antenna Keepout applies when the RM1xx is placed in
the corner of the host PCB. When RM1xx-SM cannot be placed as such, it must be placed on the edge of the host PCB
and the antenna keep out must be observed. An example is shown in Figure 9.