GSG 勁力 半導体 Gunter Semiconductor GmbH AK2124 EDITION 09/00 Receiver/Demodulator for time code signals transmitted by the transmitters DCF77 ( Germany) , MSF (UK), or WWVB (USA) For inquiry please contact : China Tel: 0086-755-3200442 Fax: 0086-755-3355520 Hong Kong Tel : 00852-26190748 Fax: 00852-24948080 e-mail [email protected] Technical Data AK2124 Edition 09/00 Radio Controlled Clock Receiver Short Description Features The AK2124 bipolar monolithic integrated circuit receives and demodulates digital time signals emitted by time signal transmitters in the long-wave range. It is designed for low-current battery operation and can be switched in power-down mode. Due to the possibility of connecting two antennas a position-independent stable operation is guaranteed. The circuit is thus capable of the selective reception of various time signal transmitters. • very low battery drain • power-down mode • two antennas connectable • several transmitters receivable Package The AK2124 is offered in 12.85 ± 0.1 0.1 2.30 +- 0.05 10.4 ± 0.2 7.4 + 0.2 ≤ 0.82 • Die Pad-layout 0.27 0.15 0.42 ±0.07 1.27 20 19 18 17 16 15 14 13 12 11 1 2 3 4 5 6 7 8 9 10 11 12 13 14 10 9 0.25 M ≥ 0.3 8 7 AK 2124 X 15 16 17 18 1 09/00 +0.05 -0.04 0.2 ± 0.1 0...10° ≤ 2.65 • SOP 20 6 5 4 2 3 1 Pinning Pins 8 and 13 of the SOP 20 package are not connected. Pad Pin Symbol Pin designation 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 01 02 03 04 05 06 07 09 10 11 12 14 15 16 17 18 19 20 A2 A1 GND E2 E1 CK SR VCC A KS CR PON CD AP2 REF E3 SA AP1 RF - output 2 RF - output 1 Ground Antenna input 2 Antenna input 1 Compensation capacity Switch controller Supply voltage Output Comparator threshold Charging capacitor (for control amplifier) Stand - by switch Demodulation capacity Operating point regulator 2 Reference voltage Booster amplifier input Antenna change-over switch Operating point regulator 1 Block Diagram and Application Circuit 330 k 77.5 kHz 680 1p 47 n 20 100 µ 2 1 18 150 n 16 22 n 15 12 A1 A2 E3 AP2 CD CR V CC AP1 SR 5 E1 a A - V2 CONTROL AMPLIFIER D V3 7 I R1 I R2 100 k 4 V R E2 B AK 2124 100 k A 47 n 17 V CC E2 E1 19 REFERENCE CURRENT SOURCE REF SA GND PON CK V CC 3 14 6 9 OFF ON 100 p 10 A COMPARATOR KS V CC 11 10 µ V CC 2 09/00 AK2124 Absolute Maximum Ratings symbol min. max. unit Supply voltage VCC 0 5.25 V Output voltage VO 0 5.25 V Antenna switch voltage VSA 0 VCC V Switch controller voltage SR VSR 0 VCC V Stand-by switch voltage PON VPON 0 VCC V Junction temperature Tj 150 °C Operating temperature Ta +85 °C -25 Recommended operational conditions Supply voltage VCC 1.4 V Frequency f 50 ... 80 kHz Operating temperature Ta 0 ... 55 °C RF input voltage ViE >3 µV Electrical Characteristics 1. Test circuits V CC V CC 47 n E2 47 n 150 n 22 n REF AP2 CD Ue2 51 1k AP1 SA E3 77.5 kHz 20 E1 Ue1 330 k 51 100 µ 19 18 17 16 PON n.c. CR KS 15 14 13 12 11 6 7 8 9 10 AK 2124 1p 1k 1 2 A2 3 A1 4 GND 5 E2 E1 CK SR n.c. V CC V R A 100 k A 100 p 4.7 n V CC V CC 2 Ue1 , Ue2 : pot core A 1100 nH/w ; 2 x 25 windings with 0.2 CuL L 09/00 AK2124 3 2. Parameters Refering to the test circuit with generator signal f = 77500 Hz ± 5 Hz pulse modulation of RF-signal from 100% to 25 % during modulation time t = 200 ms, VCC = 1.4 V ; VPON = 0 V ; Ta = 25 °C unless specified otherwise min. typ. max. Supply voltage range (+5°C < Ta < +55°C) 1.2 1.4 2.2 V Supply voltage range (-25°C < Ta < +85°C) 1.4 2.2 V Current consumption ( normal operation ) 600 1000 µA Current consumption ( Stand - by ) <1 10 µA Switch current IPON ( VPON = ground ) -15 -50 µA Switch current ISA ( VSA = VCC ) 5 10 µA Switch current ISR ( VSR = VCC ) 10 30 µA 100000 µV Input voltage 3 Antenna switch attenuation 52 dB Input impedance of the RF amplifier 750 kΩ Input impedance of the booster amplifier 95 kΩ Output impedance of the RF segment ( A1 ) 0.3 kΩ Output impedance of the RF segment ( A2 ) 7.5 kΩ RF segment amplification (on A1 at VSA = O V) 53 dB Range of input voltage booster amplifier Internal resistance of the demodulator Output voltage of the demodulator 4 unit 30 450 µV 70 kΩ 200 mVpp 09/00 AK2124 min. typ. max. unit Control time ( VSR = VCC ) for ∆Vi = 0.1 mV - 1 mV for ∆Vi = 1 mV - 0.5 mV 0.8 2.0 s s Control time ( VSR = 0V ) for ∆Vi = 0.1 mV - 1 mV for ∆Vi = 1 mV - 0.5 mV 0.8 5.0 s s Output pulse width ( VSR = 0 V ) at transmitter pulse width 200 ms for VR = 1.4 V, ViE = 3 µV 180 195 Output current IOH ( VR = 6 V ) Output current IOL ( VR = 6 V ) Output voltage VOL ( IOL = 15 µA ) 60 220 ms 10 µA 200 20 µA 200 mV Application Hints 1. RF Component An inductive coupling of signals between E1, E2 and AP1 is essential to establishing the given switch-over attenuation. The SA switch-over point is ca. 0.8 V. The output A2, with an impedance of 7.5 kΩ, has an inverted output signal ca. 5 dB lower than A1. The filter band width of the quartz filter between A1 and E3 should be set to 20...25 Hz with a series resistance of 330 kΩ. The associated signal attenuation of ca. 12 dB is also desirable when other filter configurations are applied. When the AK2124 is used as a dual standard receiver, antenna switch-over with SA is necessary, as is filtering with two different crystals from outputs A1 to E3, or A2 to E3. 2. Demodulator, Control time constants The demodulated time signal impulses are available at CD. The time constant is CD * 70 kΩ. Regulated voltage is attained at the pin CR, whereby the control-time constant is determined by a switchable decharging circuit and CR. The control rate is regulated at SR. A larger control-time constant functions at VSR = O V than at VSR = VCC. To reduce oscillating overdrive the additional connection with a series resistor of 680 Ω on the CR is recommended. 3. Receiver circuit The optimal supply voltage is 1.4 V. At applications with a voltage supply above 1.4 V it is better to connect VCC with a bias resistor so that there is about 1.4 V, whereby there is a simultaneous dynamic decoupling to other components. The output is able to bear load resistance with working voltages of up to 5.25 V independent of VCC. It is therefore advantageous to block the VCC - pin with a capacitor > 4.7 µF. The usual RF-technical aspects are valid for the PCB layout, whereby special attention should be given to the fact that between A and E3 the greatest possible area is intended for purposes of shielding. Copying is generally permitted, indicating the source. However, our consent must be obtained in all cases. MEGAXESS reserves the right to make changes in specifications at any time and without notice. The information and suggestions are given without obligation and cannot give rise to any liability, they do not indicate the availability of the components mentioned. The information included herein is believed to be accurate and reliable. However, MEGAXESS assumes no responsibility for its use; nor for any infringements of patents or of other rights of third parties which may result from its use. Megaxess GmbH Deutschland • POB 1370 • 15236 Frankfurt(Oder) • Germany Phone +49 335 2005 • FAX +49 335 3251 • Internet http://www. megaxess.de 09/00 AK2124 5