U4223B ATMEL Corporation, U4223B Datasheet - Page 6

• Manufacturer Part Number: U4223B
• Description: Time-code Receiver With A/d Converter
• Manufacturer: ATMEL Corporation

Temperature compensation of the resonant frequency is
a must if the clock is used at different temperatures.
Please ask your supplier of bar antenna material and of
capacitors for specified values of the temperature
coefficient.
Furthermore, some critical parasitics have to be consid-
ered. These are shortened loops (e.g., in the ground line
of the PCB board) close to the antenna and undesired
loops in the antenna circuit. Shortened loops decrease the
Q value of the circuit. They have the same effect like con-
ducting plates close to the antenna. To avoid undesired
loops in the antenna circuit, it is recommended to mount
the capacitor C
Absolute Maximum Ratings
Thermal Resistance
Electrical Characteristics
V
U4223B
Supply voltage
Ambient temperature range
Storage temperature range
Junction temperature
Electrostatic handling
(MIL Standard 883 D), except Pins 2, 5, 6, 14 and 15
Thermal resistance
Supply voltage range
Supply current
Set-up time after V
AGC amplifier input; IN Pin 2
Reception frequency range
Minimum input voltage
Maximum input voltage
Input capacitance to GND
6 (18)
CC
= 3 V, reference point Pin 3, input signal frequency 80 kHz, T
Parameters
res
as close as possible to the antenna coil
CC
ON
Parameters
Parameters
Without reception signal
with reception signal = 200 mV
OFF mode
V
R
res
CC
= 100 kW, Q
= 1.5 V
Test Conditions / Pin
Pin 1
Pin 1
res
> 30
or to use a twisted wire for the antenna-coil connection.
This twisted line is also necessary to reduce feedback of
noise from the microprocessor to the IC input. Long
connection lines must be shielded.
A final adjustment of the time-code receiver can be
carried out by pushing the coil along the bar antenna. The
maximum of the integrator output voltage V
Pin INT indicates the resonant point. But attention: The
load current should not exceed 1 nA, that means an input
resistance w 1 GW of the measuring device is required.
Therefore, a special DVM or an isolation amplifier is
necessary.
Symbol
Symbol
R
T
V
R
V
amb
T
thJA
CC
Symbol
stg
ESD
amb
j
V
I
V
V
C
f
CC
CC
t
in
in
in
in
= 25_C, unless otherwise specified
Min
1.2
40
40
–40 to +85
–40 to +85
Maximum
Value
2000
5.25
125
70
Typ
1.5
15
80
2
1
Rev. A7, 06-Mar-01
Max
5.25
0.1
1.5
30
25
80
K/W
Unit
Unit
_C
_C
_C
V
V
INT
Unit
kHz
mV
mA
mA
mA
mV
pF
V
s
at