WiMOD радио модуль IMST iM820A

  • WiMOD радио модуль IMST iM820A
  • WiMOD радио модуль IMST iM820A
WiMOD радио модуль IMST iM820A
  • RF data rate from 1.2kbps to 180kbps
  • Low power consumption
  • Integrated antenna or 50Ohm pad
  • Size 20.0×25.0×2.7mm

The iM820A is a compact, low power, bidirectional radio module for the 868 MHz frequency band. Using the iM820A in an application minimizes the need for an expensive and timeconsuming RF development. Fast time to market is possible with this pre-qualified module.

The iM820A is a small radio module for the 868 MHz frequency band. It provides a complete RF/MCU design including a transceiver, a microcontroller with AES coprocessor, a PCB antenna, and all necessary passive components. The iM820A has several application interfaces. For a serial communication it provides the serial interfaces UART and SPI. Furthermore it offers 9 digital I/Os (if not using SPI) and 8 GPIOs (only 6 when using the UART). All of them can be used as digital input/output and have external interrupt capability. Additionally the GPIOs can be used as input for the 8-channel ADC.

The module has a 128-bit AES security coprocessor supported in hardware. This allows encryption and decryption of data using the AES algorithm (128-bit keys) with minimal CPU usage. For low power consumption the module supports the capability to periodically wake up from sleep mode to listen for incoming RF packets. The RF data rate of the module is adjustable up to 180 kbps. Decreasing the data rate will increase the sensitivity which results in a longer RF range. To evaluate the radio link quality the iM820A supports a digital RSSI.

Integrated bootloading functionality enables the user to upgrade the firmware over the UART interface.

The module is solderable like a SMD-component and can easily be mounted on a simple carrier board with a minimum of required external connections. It is RoHS compliant and pre-qualified in accordance to ETSI EN 300 220-2 V2.1.2.

Key Features

  • Compact radio module for 868MHz
  • Low power consumption, wake on radio (WOR) functionality
  • 128-bit AES security coprocessor
  • RF data rate from 1.2kbps to 180kbps
  • Digital RSSI support
  • UART and SPI interface
  • Sample applications available
  • Bootloading functionality for firmware update
  • Solderable like a SMD component
  • Integrated antenna or 50Ohm pad
  • Software- and pin-compatible to the iM221A


    • Security and access systems (wireless locking system)
    • Battery driven wireless sensor and actor systems
    • Home-, building-, industrial automation
    • Remote control
    • Metering systems (data logging)

Absolute Maximum Ratings

  1. Supply voltage-0.3V to VCC +0.3V (Voltage with respect to GND)
  2. Input voltage-0.3V to VCC +0.3V (Digital pins.)0 to VCC-0.2V (Digital pins.)
  3. DC current4mA (Per digital pin)20mA (Only radio module pin 14 and pin 15)
  4. Input RF level+10dBm
  5. Operating temperature3.3V~ 4.3V , 3.8V Typ.
  6. Operation Temperature-20 °C to +70 °C
  7. Storage temperature-40 °C to +85 °C

General Characteristics

  1. Operating supply voltage VCC2.3 to 3.6V, Typ. 3.0V
  2. Current consumptiontyp. 23mA (Receive)typ. 31mA (Transmit @ max. RF power level 50Ω pin ANT))typ. 34mA (Transmit @ max. RF power level integrated PCB antenna)typ. 5mA (μC active, TRX off)typ. 1μA (Power down)
  3. Dimension (L x W x H)20 x 25 x 2.7mm, ±0.2mm
  4. MCU operation frequency26MHz
  5. Real time oscillator frequency32.768kHz
  6. Memory (Flash)32KB (Minimum endurance: 1000 write/erase cycles)
  7. Memory (RAM)4KB

Module Interface Characteristics

  1. Digital output voltageVCC-0.25V to VCC (High level)GND to 0.3V (Low level)
  2. Digital input voltage0.7V x VCC to VCC (High level)GND to 0.3V x VCC (Low level)
  3. I/O pin pull-up/pull-down resistor20kΩ (Except pin 14 and pin 15)
  4. Pulse width on /RESET pinmin. 250ns (Low active pin)
  5. Power-On-Reset (POR) threshold1.5V (Rising edge)0.9V (Falling edge)
  6. UART baud ratetyp. 38.4kbps (Further data rates are available on demand)
  7. SPI baud ratemax. 3250kbps
  8. ADC resolution7 to 12Bit
  9. ADC conversion time20 to 132μs (Depends on ADC resolution (68 μs @ 10 bit resolution)
  10. ADC input resistance197kΩ
  11. Analog int. reference voltage (Vref)1.25V
  12. Analog input voltageGND to Vref

RF Characteristics

  1. Frequency range863 to 870MHz
  2. RF data rateup to 180kbps
  3. RF output powermax. +4dBm (e.i.r.p.) (With integrated PCB antenna)max. +7dBm (Measured at 50Ω (pin ANT))
  4. RF output power range40dB
  5. RF sensitivity (PCB antenna / 50Ω)typ. -104/-110dBm (1.2kbps data rate / 1% PER)typ. -96/-102dBm (38.4kbps data rate / 1% PER)typ. -88/-94dBm (180kbps data rate / 1% PER)
  6. Modulation techniquesGFSK
  7. RangeUp to 1100m (Outdoor (line of sight) with external antenna (0dBi) on pin ANT)