|
|
PDF NJ8821 Data sheet ( Hoja de datos )
| Número de pieza | NJ8821 | |
| Descripción | FREQUENCY SYNTHESISER (MICROPROCESSOR INTERFACE) WITH RESETTABLE COUNTERS | |
| Fabricantes | Zarlink Inc | |
| Logotipo |  |
|
Hay una vista previa y un enlace de descarga de NJ8821 (archivo pdf) en la parte inferior de esta página. Total 10 Páginas | ||
|
No Preview Available !
This product is obsolete.
This information is available for your
convenience only.
For more information on
Zarlink’s obsolete products and
replacement product lists, please visit
http://products.zarlink.com/obsolete_products/
1 page  
NJ8821
PIN DESCRIPTIONS
Pin no. Name
Description
1 PDA Analog output from the sample and hold phase comparator for use as a ‘fine’ error signal. Output at
(VDD2VSS)/2 when the system is in lock. Voltage increases as fv phase lead increases; voltage
decreases as fr phase lead increases. Output is linear over only a narrow phase window, determined
by gain (programmed by RB).
2 PDB Three-state output from the phase/frequency detector for use as a ‘coarse’ error signal.
fv. fr or fv leading: positive pulses with respect to the bias point VBIAS
fv , fr or fr leading: negative pulses with respect to the bias point VBIAS
fv = fr and phase error within PDA window: high impedance.
3 LD An open-drain lock detect output at low level when phase error is within PDA window (in lock); high
impedance at all other times.
4 FIN The input to the main counters, normally driven from a prescaler, which may be AC-coupled or, when
a full logic swing is available, may be DC-coupled.
5 VSS Negative supply (ground).
6 VDD Positive supply.
7, 8 OSC IN/ These pins form an on-chip reference oscillator when a series resonant crystal is connected across
OSC OUT them. Capacitors of appropriate value are also required between each end of the crystal and ground
to provide the necessary additional phase shift. An external reference signal may, alternatively, be
applied to OSC IN. This may be a low-level signal, AC-coupled, or if a full logic swing is available it may
be DC-coupled. The program range of the reference counter is 3 to 2047, with the division ratio being
twice the programmed number.
9,10, 11, 12 D0-D3 Data on these inputs is transferred to the internal data latches during the appropriate data read time
slot. D3 is MSB, D0 is LSB.
13 NC No connection
14 PE This pin is used as a strobe for the data. A logic ‘1’ on this pin transfers data from the D0-D3 pins to
the internal latch addressed by the data select (DS0-DS2) pins . A logic ‘0’ disables the data inputs.
15, 16, 17 DS0-DS2 Data select inputs for addressing the internal data latches
18 MC Modulus control output for controlling an external dual-modulus prescaler. MC will be low at the beginning
of a count cycle and will remain low until the ‘A’ counter completes its cycle. MC then goes high and
remains high until the ‘M’ counter completes its cycle, at which point both ‘A’ and ‘M’ counters are reset.
This gives a total division ratio of MP1A, where P and P11 represent the dual-modulus prescaler
values. The program range of the ‘A’ counter is 0-127 and therefore can control prescalers with a
division ratio up to and including 4128/129. The programming range of the ‘M’ counter is 8-1023
and, for correct operation, M>A. Where every possible channel is required, the minimum total division
ratio should be P 22P.
19 RB An external sample and hold phase comparator gain programming resistor should be connected
between this pin and VSS.
20 CH An external hold capacitor should be connected between this pin and VSS.
2·0
VDD = 5V
OSC IN, FIN = 0V TO 5V SQUARE WAVE
1·5
8
VDD = 5V
7 FIN = LOW FREQUENCY
0V TO 5V SQUARE WAVE
6
OSC IN
1·0
FIN
0·5
TOTAL SUPPLY CURRENT IS
THE SUM OF THAT DUE TO FIN
AND OSC IN
12 34 5 6789
INPUT FREQUENCY (MHz)
Fig. 3 Typical supply current v. input frequency
10
5
10MHz
4
1MHz
3
2
1
0·2 0·4 0·6 0·8 1·0 1·2 1·4 1·6
INPUT LEVEL (V RMS)
Fig. 4 Typical supply current v. input level, OSC IN
3
5 Page | ||
| Páginas | Total 10 Páginas | |
| PDF Descargar | [ Datasheet NJ8821.PDF ] | |
Hoja de datos destacado
| Número de pieza | Descripción | Fabricantes |
| NJ8820 | FREQUENCY SYNTHESISER (PROM INTERFACE) | Zarlink Inc |
| NJ8821 | FREQUENCY SYNTHESISER (MICROPROCESSOR INTERFACE) WITH RESETTABLE COUNTERS | Zarlink Inc |
| NJ8821 | FREQUENCY SYNTHESISER |  General Electric Company |
| Número de pieza | Descripción | Fabricantes |
| SLA6805M | High Voltage 3 phase Motor Driver IC. |
 Sanken |
| SDC1742 | 12- and 14-Bit Hybrid Synchro / Resolver-to-Digital Converters. |
 Analog Devices |
|
DataSheet.es es una pagina web que funciona como un repositorio de manuales o hoja de datos de muchos de los productos más populares, |
| DataSheet.es | 2020 | Privacy Policy | Contacto | Buscar |