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DA1016B.001

27 January, 2004

TYPICAL APPLICATION

Note 1: Crystal

The crystal as well as ferrite antenna frequencies are chosen according to the time signal system. Ferrite

antenna frequencies and recommended crystal frequencies are presented in table 1. For more details about

crystal selection see DAEV1016B.

Table 1

Time-Signal System Frequencies

Time-Signal System

Location

Frequency

Recommended Crystal Frequency

Unit

DCF77

Germany

77.5

77.503

kHz

MSF

United Kingdom

60

60.003

kHz

WWVB

USA

60

60.003

kHz

JJY

Japan

40 and 60

40.003 and 60.003

kHz

Note 2: AGC Capacitor

The AGC capacitor value is also chosen according to time-signal system. Recommended capacitor values are

presented in table 2. WWVB and JJY systems require external control of AON (=AGC on) pin to receive pulses

correctly. For more details about required control of AON in WWVB and JJY systems see DAEV1016B.

The AGC and DEC capacitors should have low leakage currents due to very small 40 nA signal currents

through the capacitors. The insulation resistance of these capacitors should be higher than 70 M

Ω. Also probes

with at least 100 M

Ω impedance should be used for voltage probing of AGC and DEC pins.

Table 2

Recommended AGC Capacitor Value

Time-Signal System

Recommended AGC Capacitor Value

DCF77

470nF

MSF

1uF

WWVB

220nF + Special AGC Control

JJY

220nF + Special AGC Control

AGC Amplifier

Demodulator

&

Comparator

Power Supply/Biasing

RFI

OUT

QI

QO

VSS

AGC

DEC

Receiver

output

Ferrite-

Antenna

Note 1

AON (=AGC on)

VDD

1.4 V

PDN

Note 2

X1

0.47…1 uF

47 nF