- 您现在的位置：买卖IC网 > PDF目录61664 > MC12429FA (INTEGRATED DEVICE TECHNOLOGY INC) 400 MHz, OTHER CLOCK GENERATOR, PQFP32 PDF资料下载
参数资料
| 型号： | MC12429FA |
| 厂商： | INTEGRATED DEVICE TECHNOLOGY INC |
| 元件分类： | 时钟产生/分配 |
| 英文描述： | 400 MHz, OTHER CLOCK GENERATOR, PQFP32 |
| 封装： | LQFP-32 |
| 文件页数： | 5/10页 |
| 文件大小： | 383K |
| 代理商： | MC12429FA |
MC12429
FREESCALE SEMICONDUCTOR ADVANCED CLOCK DRIVERS DEVICE DATA
355
Figure 3. MC12429 Block Diagram (28-Lead PLCC Pinout)
PROGRAMMING INTERFACE
Programming the device amounts to properly configuring the
internal dividers to produce the desired frequency at the
outputs. The output frequency can by represented by this
formula:
FOUT = (FXTAL ÷ 16) x M ÷ N(1)
Where FXTAL is the crystal frequency, M is the loop divider
modulus, and N is the output divider modulus. Note that it is
possible to select values of M such that the PLL is unable to
achieve loop lock. To avoid this, always make sure that M is
selected to be 200
≤ M ≤ 400 for a 16MHz input reference.
Assuming that a 16MHz reference frequency is used the
above equation reduces to:
FOUT = M
÷ N
Substituting the four values for N (1, 2, 4, 8) yields:
From these ranges the user will establish the value of N
required, then the value of M can be calculated based on the
appropriate equation above. For example if an output frequency
of 131MHz was desired the following steps would be taken to
identify the appropriate M and N values. 131MHz falls within the
frequency range set by an N value of 2 so N [1:0] = 01.
For N = 2 FOUT = M
÷ 2 and M = 2 x FOUT. Therefore
M = 131 x 2 = 262, so M[8:0] = 100000110. Following this same
procedure a user can generate any whole frequency desired
between 25 and 400MHz. Note that for N > 2 fractional values
of FOUT can be realized. The size of the programmable
frequency steps (and thus the indicator of the fractional output
frequencies achievable) will be equal to FXTAL
÷ 16 ÷ N.
For input reference frequencies other than 16MHz the set of
appropriate equations can be deduced from equation 1. For
computer applications another useful frequency base would be
16.666MHz. From this reference one can generate a family of
output frequencies at multiples of the 33.333MHz PCI clock. As
an example to generate a 133.333MHz clock from a
16.666MHz reference the following M and N values would be
used:
FOUT = 16.666
÷ 16 x M ÷ N = 1.0416 x M ÷ N
Let N = 2, M = 133.3333
÷ 1.0416 x 2 = 256
9-BIT SR
2-BIT SR
3-BIT SR
DIV 16
16MHz
S_LOAD
P_LOAD
S_DATA
S_CLOCK
XTAL1
XTAL2
OSC
4
5
PHASE
DETECTOR
28
7
9-BIT DIV M
COUNTER
LATCH
VCO
DIV N
(1, 2, 4, 8)
LATCH
200–400
MHz
FOUT
+3.3 or 5.0V
25
24
23
VCC0
LATCH
TEST
20
+3.3 or 5.0V
PLL_VCC
1MHz
FREF
0
1
27
26
0
1
VCC1
+3.3 or 5.0V
M[8:0]
9
8, 16
N[1:0]
2
17, 18
21
22, 19
OE
6
Table 2. Output Frequency Range
N
FOUT
Output Frequency Range
1
2
4
8
M
M / 2
M / 4
M / 8
200 – 400 MHz
100 – 200 MHz
50 – 100 MHz
25 – 50 MHz
MC12429
High Frequency Clock Synthesizer
NETCOM
IDT High Frequency Clock Synthesizer
Freescale Timing Solutions Organization has been acquired by Integrated Device Technology, Inc
MC12429
4
相关PDF资料 |
PDF描述 |
|---|---|
| MC2841-11-1 | 0.1 A, SILICON, SIGNAL DIODE |
| MC2841-T13-1 | 0.1 A, SILICON, SIGNAL DIODE |
| MC2846-11-1 | 0.1 A, 2 ELEMENT, SILICON, SIGNAL DIODE |
| MC54HC597J/883 | HC/UH SERIES, 8-BIT RIGHT PARALLEL IN SERIAL OUT SHIFT REGISTER, TRUE OUTPUT, CDIP16 |
| MC74F2968N | DRAM CONTROLLER, PDIP48 |
相关代理商/技术参数 |
参数描述 |
|---|---|
| MC12429FN | 制造商:MOTOROLA 制造商全称:Motorola, Inc 功能描述:HIGH FREQUENCY PLL CLOCK GENERATOR |
| MC12430FA | 制造商:MOTOROLA 制造商全称:Motorola, Inc 功能描述:HIGH FREQUENCY PLL CLOCK GENERATOR |
| MC12430FN | 制造商:MOTOROLA 制造商全称:Motorola, Inc 功能描述:HIGH FREQUENCY PLL CLOCK GENERATOR |
| MC12439 | 制造商:MOTOROLA 制造商全称:Motorola, Inc 功能描述:HIGH FREQUENCY PLL CLOCK GENERATOR |
| MC12439FN | 制造商:Motorola Inc 功能描述: 制造商:Motorola Inc 功能描述:MISCELLANEOUS CLOCK GENERATOR, 28 Pin, Plastic, PLCC |
发布紧急采购，3分钟左右您将得到回复。