DAEV6180B1COB.004 23 March, 2012 TIME SIGNAL RECEIVER MODULE • Tuned ferrite antenna • AM receiver IC board • Reception of: - German DCF77 - US WWVB - British MSF - Japanese JJY60 INTRODUCTION The time signal receiver module comprises of a ferrite antenna and an AM receiver IC printed circuit board. The board includes a MAS6180B1 AM receiver IC accompanied with necessary filter crystal and capacitor components. The circuitry includes also an RC-filter for the supply voltage. The EB6180B1COB77K5A1 module is tuned for 77.5 kHz and suitable for receiving German DCF77 time signal transmission whereas the EB6180B1COB60K0A1 and A2 modules are tuned for 60 kHz suitable for receiving US WWVB, British MSF and Japanese JJY60 time signal transmissions. The A2 module with 100mm antenna bar is especially suited for WWVB to cover the weak signal areas. The MAS6180B1 AM receiver IC includes amplifier, demodulator and comparator blocks that transforms the received AM transmission into series of pulse width coded digital pulses which can be directly processed by an appropriate digital circuitry such as a micro controller unit (MCU). PIN DESCRIPTION Pin ID Type Function Note P1 DI PDN (power down) control pin HIGH = receiver off LOW = receiver on T P2 G V AON DO NC G P DI Time pulse output Supply ground Supply voltage AGC on/off control (optional) Leave unconnected Leave unconnected when not used D = Digital, P = Power, G = Ground, I = Input, O = Output, NC = Not Connected PCB backside pin marking 1 (4) DAEV6180B1COB.004 23 March, 2012 APPLICATION INFORMATION Antenna orientation Horizon The magnetic field component of the propagating long wave time signal transmission has a horizontal polarization thus the ferrite antenna should be oriented horizontally to maximize the signal (see figure 1). Figure 1. Antenna orientation relative to ground Transmitter antenna Ferrite antenna Ground The ferrite antenna should also be pointing orthogonally relative to the transmitter (see figure 2). Figure 2. Antenna orientation relative to transmitter station The ferrite bar antenna should be located as far as possible from conductive metal walls, PCB ground plane or ferromagnetic objects (speakers). All those objects affect the antenna tuning and can attenuate the received signal. To avoid noise coupling the ferrite antenna should also not be pointing towards noisy electronic circuits (figure 3). It is a good practice to turn off all unnecessary electronic circuits when receiving the weak radio transmission. Figure 3. Antenna orientation relative to noisy electric circuits Getting a signal The antenna is sensitive for magnetic and electric disturbances. As an example, in digital radio controlled clocks it is known that LCD displays, refreshed using a 32Hz signal, has a1875th odd harmonic hitting exactly at 60kHz and its amplitude can be strong enough (µVrms level) to reduce the sensitivity. The antenna and module placement is critical and one should maximize distance to other disturbing electronics and metal/ferrous parts which might affect the antenna and the reception. A good place to start is to put the module close to a window and turn the antenna to an optimal position relative the transmitter (see the figure 2 above). As the second step trigger the fast startup by moving PDN control from power down (PDN=VDD) to power up (PDN=VSS) which will make the AGC find its level within a few seconds if the receiving conditions are sufficient. Initially the OUT signal should be high but soon after finding a signal (or disturbance in case of poor SNR) the output goes low and after a few seconds it should start receiving pulses. If the output stays low all the time there is probably some disturbance stronger than the signal. If the signal is bad, change location and repeat the fast startup by setting PDN=VDD (power down) to PDN=VSS (power up). 2 (4) DAEV6180B1COB.004 23 March, 2012 ELECTRICAL CHARACTERISTICS Operating Conditions: VDD = 1.5V, Temperature = 27°C, unless otherwise specified. Parameter Symbol Operating Voltage Current Consumption Conditions VDD IDD Stand-By Current Receiving Frequency IDDoff fIN Sensitivity EMIN VDD=1.5 V, weak signal VDD=1.5 V, strong signal VDD=3.6 V, weak signal VDD=3.6 V, strong signal Min Typ Max 1.1 1.5 66 40 68 42 3.6 31 24 module EB6180B1COB77K5A1 module EB6180B1COB60K0A1 module EB6180B1COB60K0A2 See ordering information below. Unit V µA 85 65 0.1 77.5 60 60 25 µA kHz µV/m Note: For more detailed electrical characteristics see MAS6180B1 AM receiver IC datasheet MECHANICAL DIMENSIONS Parameter Symbol Conditions Min Typ Max Unit length LA A1 antenna bar A2 antenna bar WA HA 60 100 10 9 +3 +3 +0.3 +0.3 mm width height -3 -3 -0.3 -0.3 LPCB W PCB TPCB -0.2 -0.2 -0.1 25.0 13.5 1.3 +0.2 +0.2 +0.1 mm Antenna PCB length width thickness 100±3 (A2 antenna bar) 10±0.3 9±0.3 60±3 (A1 antenna bar) 10±0.3 9±0.3 25.0±0.2 7.8 10.2 10.5 1.3±0.1 13.5±0.2 Diameter of two corner located assembly holes is 2mm. 2.54 (4x) 21.4 3 (4) DAEV6180B1COB.004 23 March, 2012 CIRCUIT SCHEMATIC Note: The two attachment holes on the PCB corners have electrical connection to AON and GND. Ensure proper isolation when attaching to conductive enclosure. ORDERING INFORMATION Product Code Product Antenna EB6180B1COB77K5A1 EB6180B1COB60K0A1 EB6180B1COB60K0A2 77.5kHz DCF77 receiver module 60kHz WWVB/MSF/JJY60 receiver module 60kHz WWVB/MSF/JJY60 receiver module A1: 60x10x9 mm A1: 60x10x9 mm A2: 100x10x9 mm Note: Modules are RoHS compliant. MICRO ANALOG SYSTEMS OY CONTACTS Micro Analog Systems Oy Kutomotie 16 FI-00380 Helsinki, FINLAND Tel. +358 10 835 1100 Fax +358 10 835 1119 http://www.mas-oy.com NOTICE Micro Analog Systems Oy reserves the right to make changes to the products contained in this data sheet in order to improve the design or performance and to supply the best possible products. Micro Analog Systems Oy assumes no responsibility for the use of any circuits shown in this data sheet, conveys no license under any patent or other rights unless otherwise specified in this data sheet, and makes no claim that the circuits are free from patent infringement. Applications for any devices shown in this data sheet are for illustration only and Micro Analog Systems Oy makes no claim or warranty that such applications will be suitable for the use specified without further testing or modification. 4 (4)