|
|
PDF MC12429FN Data sheet ( Hoja de datos )
| Número de pieza | MC12429FN | |
| Descripción | HIGH FREQUENCY PLL CLOCK GENERATOR | |
| Fabricantes | Motorola Semiconductors | |
| Logotipo |  |
|
Hay una vista previa y un enlace de descarga de MC12429FN (archivo pdf) en la parte inferior de esta página. Total 10 Páginas | ||
|
No Preview Available !
MOTOROLA
SEMICONDUCTOR TECHNICAL DATA
High Frequency Clock Generator
The MC12429 is a general purpose synthesized clock source targeting
applications that require both serial and parallel interfaces. Its internal
VCO will operate over a range of frequencies from 400 to 800MHz. The
differential PECL output can be configured to be the VCO frequency
divided by 2, 4, 8 or 16. With the output configured to divide the VCO
frequency by 2, and with a 16.000MHz external quartz crystal used to
provide the reference frequency, the output frequency can be specified in
1MHz steps. The PLL loop filter is fully integrated so that no external
components are required.
MC12429
HIGH FREQUENCY PLL
CLOCK GENERATOR
• 25 to 400MHz Differential PECL Outputs
• ±25ps Peak–to–Peak Output Jitter
• Fully Integrated Phase–Locked Loop
• Minimal Frequency Over–Shoot
• Synthesized Architecture
• Serial 3–Wire Interface
• Parallel Interface for Power–Up
• Quartz Crystal Interface
• 28–Lead PLCC Package
• Operates from 3.3V or 5.0V Power Supply
Functional Description
The internal oscillator uses the external quartz crystal as the basis of
its frequency reference. The output of the reference oscillator is divided
by 8 before being sent to the phase detector. With a 16MHz crystal, this
provides a reference frequency of 2MHz. Although this data sheet
illustrates functionality only for a 16MHz crystal, any crystal in the
10–25MHz range can be used.
FN SUFFIX
28–LEAD PLCC PACKAGE
CASE 776–02
The VCO within the PLL operates over a range of 400 to 800MHz. Its output is scaled by a divider that is configured by either
the serial or parallel interfaces. The output of this loop divider is also applied to the phase detector.
The phase detector and loop filter attempt to force the VCO output frequency to be M times the reference frequency by
adjusting the VCO control voltage. Note that for some values of M (either too high or too low) the PLL will not achieve loop lock.
The output of the VCO is also passed through an output divider before being sent to the PECL output driver. This output divider
(N divider) is configured through either the serial or the parallel interfaces, and can provide one of four division ratios (2, 4, 8, or
16). This divider extends performance of the part while providing a 50% duty cycle.
The output driver is driven differentially from the output divider, and is capable of driving a pair of transmission lines terminated
in 50Ω to VCC – 2.0. The positive reference for the output driver and the internal logic is separated from the power supply for the
phase–locked loop to minimize noise induced jitter.
The configuration logic has two sections: serial and parallel. The parallel interface uses the values at the M[8:0] and N[1:0]
inputs to configure the internal counters. Normally, on system reset, the P_LOAD input is held LOW until sometime after power
becomes valid. On the LOW–to–HIGH transition of P_LOAD, the parallel inputs are captured. The parallel interface has priority
over the serial interface. Internal pullup resistors are provided on the M[8:0] and N[1:0] inputs to reduce component count in the
application of the chip.
The serial interface centers on a fourteen bit shift register. The shift register shifts once per rising edge of the S_CLOCK input.
The serial input S_DATA must meet setup and hold timing as specified in the AC Characteristics section of this document. The
configuration latches will capture the value of the shift register on the HIGH–to–LOW edge of the S_LOAD input. See the
programming section for more information.
The TEST output reflects various internal node values, and is controlled by the T[2:0] bits in the serial data stream. See the
programming section for more information.
1/97
© Motorola, Inc. 1997
1
REV 5
1 page  
MC12429
SCLOCK
FREF
MCNT
PLL 12429
M COUNTER
VCO_CLK
0
1
SEL_CLK
SDATA SHIFT
REG
14–BIT
T0
T1
T2
LATCH
SLOAD
Reset
PLOADB
DECODE
N DIVIDE
(2, 4, 8, 16)
FOUT
(VIA ENABLE GATE)
FDIV4
MCNT
LOW
FOUT
MCNT
FREF
HIGH
7
TEST
MUX
0
TEST
• T2=T1=1, T0=0: Test Mode
• SCLOCK is selected, MCNT is on TEST output, SCLOCK DIVIDE BY N is on FOUT pin
PLOADB acts as reset for test pin latch. When latch reset T2 data is shifted out TEST pin.
Figure 4. Serial Test Clock Block Diagram
DC CHARACTERISTICS (TA = 0° to 70°C, VCC = 3.3V to 5.0V ±5%)
Symbol
Characteristic
Min Typ
VIH
VIL
IIN
VOH
VOL
VOH
Input HIGH Voltage
Input LOW Voltage
Input Current
Output HIGH Voltage
Output LOW Voltage
Output HIGH Voltage
2.0
TEST
TEST
FOUT
FOUT
2.5
2.17
VOL
Output LOW Voltage
FOUT
FOUT
1.41
ICC
Power Supply Current
VCC
PLL_VCC
1. Output levels will vary 1:1 with VCC0 variation.
2. 50Ω to VCC – 2.0V pulldown.
85
15
Max Unit
Condition
V VCC = 3.3 to 5.0V
0.8 V VCC = 3.3 to 5.0V
1.0 mA
V IOH = –0.8mA
0.4 V IOL = 0.8mA
2.50 V VCC0 = 3.3V (Notes 1., 2.)
1.76 V VCC0 = 3.3V (Notes 1., 2.)
100 mA
20
TIMING SOLUTIONS
BR1333 — Rev 6
5
MOTOROLA
5 Page | ||
| Páginas | Total 10 Páginas | |
| PDF Descargar | [ Datasheet MC12429FN.PDF ] | |
Hoja de datos destacado
| Número de pieza | Descripción | Fabricantes |
| MC12429FN | HIGH FREQUENCY PLL CLOCK GENERATOR | Motorola Semiconductors |
| 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 |