Rainbow Electronics RFM12 User Manual

RFM12

RFM12

UNIVERSAL ISM BAND FSK TRANSCEIVER MODULE

RFM12

（the purpose of this spec covers mainly for the
physical characteristic of the module, for register
configure and its related command info please refer
to

RF12 data sheets）

General Introduction

RFM12 is a low costing ISM band transceiver
module implemented with unique PLL. It works
signal ranges from 315/433/868/915MHZ bands,
comply with FCC, ETSI regulation. The SPI
interface is used to communicate with
microcontroller for parameter setting.

Features:

• Low costing, high performance and price ratio

• Tuning free during production

• PLL and zero IF technology

• Fast PLL lock time

• High resolution PLL with 2.5 KHz step

• High data rate (up to 115.2 kbps with internal demodulator，with external RC filter highest data rate is
256 kbps)

• Differential antenna input

• Automatic antenna tuning

• Programmable TX frequency deviation (from 15 to 240 KHz)

• Programmable receiver bandwidth (from 67 to 400 kHz)

• Analog and digital signal strength indicator (ARSSI/DRSSI)

• AFC

• DQD

• Internal data filtering and clock recovery

• RX synchron pattern recognition

• SPI interface

• Clock and reset signal output for external MCU use

• 16 bit RX Data FIFO

• Two 8 bit TX data registers

• 10MHz crystal for PLL timing

• Wakeup timer

• 2.2V - 5.4V power supply

• Low power consumption

• Standby current less than 0.3uA

Tel: [phone] Fax: [phone] E-mail: [e-mail]

http://www.hoperf.com

RFM12

T ypical Application：

• Remote control

• Remote sensor

• Wireless data collection

• Home security system

• Toys

• Tire pressure monitoring system

Pin Definition：

SMD DIP

definition Type Function
nINT/VDI DI/ DO Interrupt input (active low)/Valid data indicator
VDD S Positive power supply
SDI DI SPI data input
SCK DI SPI clock input
nSEL DI Chip select (active low)
SDO DO Serial data output with bus hold
nIRQ DO
FSK/DATA/nFFS DI/DO/DI Transmit FSK data input/ Received data output (FIFO not used)/ FIFO

DCLK/CFIL/FFIT DO/AIO/DO Clock output (no FIFO )/ external filter capacitor(analog mode)/ FIFO

CLK DO Clock output for external microcontroller
nRES DIO
GND S Power ground

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Interrupts request output（active low）

select

interrupts(active high)when FIFO level set to 1, FIFO empty
interruption can be achieved

Reset output（active low）

http://www.hoperf.com

RFM12

Electrical Parameter：

Maximum（not at working mode）

symbol parameter minimum maximum Unit
V

dd

V

in

I

in

ESD Human body model 1000 V
T

st

T

ld

Recommended working range

symbol parameter minimum maximum Unit
V

dd

T

op

DC characteristic

symbol parameter Remark minimum typical maximum Unit
I

dd_TX_0

I

dd_TX_PMAX

I

dd_RX

I

x

I

pd

I

lb

V

lb

V

lba

V

il

V

ih

I

il

I

ih

V

ol

V

oh

Positive power supply -0.5 6.0 V
All pin input level -0.5 Vdd+0.5 V
Input current except power -25 25 mA

Storage temperature -55 125
Soldering temperature(10s) 260

℃
℃

Positive power supply 2.2 5.4 V
Working temperature -40 85

Supply current
(TX mode, P

out

= 0dBm)

315,433MHz band
868MHz band

13

915MHz band
Supply current
(TX mode, P

out

= P

max

315,433MHz band

)

868MHz band

21

915MHz band
Supply current
(RX mode)

315,433MHz band

868MHz band

10

915MHz band
Stand by current Crystal and base band

16
17

mA
24
25

mA
12
13
3．0 3．5

℃

mA

mA

on
Sleep mode current All blocks off 0.3 uA
Low battery detection 0.5 uA
Low battery step 0.1V per step 2.2 5.3 V
Low battery detection

75 mV
accuracy
Low level input 0.3*V
High level input 0.7*V

V

dd

V

dd

Leakage current Vil=0V -1 1 uA
Leakage current Vih=Vdd, Vdd=5.4V -1 1 uA
Low level output Iol=2mA 0.4 V
High level output Ioh=-2mA Vdd-0.4 V

Tel: [phone] Fax: [phone] E-mail: [e-mail]

http://www.hoperf.com