U4223B Datasheet, PDF (2/18 Pages) ATMEL Corporation – Time-Code Receiver with A/D Converter

U4223B
Pin Description
VCC ¹
IN ²
GND 3
SB ₄
Q1A ₅
Q1B ₆
U4223B
REC 7
INT ₈
DEC ₉
FLA ₁₀
20 D0 (LSB)
19 D1
18 D2
17 D3 (MSB)
16 PON
15 Q2B
14 Q2A
13 SL
12 CLK
11 FLB
Figure 2. Pinning
Pin Symbol
Function
1
VCC Supply voltage
2
IN Amplifier – Input
3
GND Ground
4
SB Bandwidth control
5
Q1A Crystal filter 1
6
Q1B Crystal filter 1
7
REC Rectifier output
8
INT Integrator output
9
DEC Decoder input
10 FLA Lowpass filter
11 FLB Lowpass filter
12 CLK Clock input for ADC
13
SL AGC hold mode
14 Q2A Crystal filter 2
15 Q2B Crystal filter 2
16 PON Power ON/OFF control
17
D3 Data out MSB
18
D2 Data out
19
D1 Data out
20
D0 Data out LSB
IN
A ferrite antenna is connected between IN and VCC. For
high sensitivity, the Q factor of the antenna circuit should
be as high as possible. Please note that a high Q factor
requires temperature compensation of the resonant
frequency in most cases. Specifications are valid for
Q>30. An optimal signal-to-noise ratio will be achieved
by a resonant resistance of 50 to 200 kW.
VCC
SB
A resistor R_SB is connected between SB and GND. It
controls the bandwidth of the crystal filters. It is recom-
mended: R_SB = 0 W for DCF 77.5 kHz, R_SB = 10 kW for
60 kHz WWVB and R_SB = open for JG2AS 40 kHz.
SB
IN
Figure 3.
Figure 4.
GND
2 (18)
Rev. A7, 06-Mar-01