shielding that are required to pass EMI regulations. The
ASM3P2853A modulates the output of PLL in order to
spread the bandwidth of a synthesized clock, thereby
decreasing the peak amplitudes of its harmonics. This
results in significantly lower system EMI compared to the
typical narrow band signal produced by oscillators and
most clock generators. Lowering EMI by increasing a
signal’s bandwidth is called spread spectrum clock
generation.
Modulation rate: 39 KHz.
Spread Spectrum ON/OFF control
Supply voltage range 2.5V ± 5%.
Available in 8-pin SOIC package.
Commercial Temperature range.
Applications
ASM3P2853A is targeted towards EMI management for
high speed digital applications such as PC peripheral
devices, consumer electronics and embedded controller
systems.
Product Description
The ASM3P2853A is a versatile spread spectrum
frequency
modulator.
The
ASM3P2853A
reduces
electromagnetic interference (EMI) at the clock source.
The ASM3P2853A allows significant system cost savings
by reducing the number of circuit board layers and
Block Diagram
V
DD
PWDNB
XIN
XOUT
Crystal
Oscillator
PLL1
USB Clock
(48 MHz
Unmodulated)
50 MHz
Modulated
SSONB
PLL2
V
SS
Alliance Semiconductor
2575 Augustine Drive
•
Santa Clara CA
•
Tel: 408-855-4900
•
Fax: 408-855-4999
•
www.alsc.com
December 2004
rev 0.7
Pin Configuration
ASM3P2853A
XIN
XOUT
V
DD
V
SS
1
2
3
4
8
50 MHz
USB Clock
SSONB
PWDNB
7
ASM3P2853A
6
5
Pin Description
Pin Name
XIN
Type
I
Description
Connection to crystal or external reference frequency input. This pin has dual
functions. It can be connected either to an external crystal or an external
reference clock.
Connection to crystal. If using an external reference clock, this pin must be left
unconnected.
Power supply for the analog and digital blocks
Ground to entire chip.
Power-down control pin. Pull low to enable the power-down mode. Connect to
VDD, if not used.
Digital logic input used to enable spread spectrum function (Active LOW).
Spread spectrum is enabled when LOW, disabled when HIGH.
Clock output -1 (48 MHz unmodulated)
Clock output -2 (50 MHz modulated)
XOUT
V
DD
V
SS
PWDNB
SSONB
USB Clock
50 MHz
O
P
P
I
I
O
O
Peak EMI Reducing Solution
2 of 8
December 2004
rev 0.7
Absolute Maximum Ratings
Symbol
V
DD
V
I
V
O
I
IK
I
OK
T
J
Input voltage, DC
Output voltage, DC
Input clamp current (V
I
<0 or V
I
>V
DD
)
Output clamp current (V
I
<0 or V
I
>V
DD
)
Junction temperature
Lead temperature (soldering 10 sec)
Input static discharge voltage protection
(MIL –STD 883E, Method 3015.7)
reliability.
ASM3P2853A
Parameter
Supply voltage, DC
Rating
(V
SS
– 0.5) to 7
(V
SS
-0.5) to (V
DD
+0.5)
(V
SS
-0.5) to (V
DD
+ 0.5)
-50 to +50
-50 to +50
150
260
2
Unit
V
V
V
mA
mA
°C
°C
kV
Note: These are stress ratings only and functional operation is not implied. Exposure to absolute maximum ratings for extended periods may affect device
I want to add a background image to a BUTTON in VS2005 (it seems that the ICON is not clear enough, so the BITMAP image is better). I have used many methods in EVC and VC, but none of them work. Gener...
In electronic products and equipment, the circuit board is an indispensable component, which plays the role of electrical and mechanical connection of the circuit system. How to arrange and combine th...
#define uint unsigned int // can be seen as global #define uchar unsigned char #include
////////////////////////////////////////////////////////////////////////// sbit CTL_485=P2^7; //485 enable bit R...
In the past few days, the Chinese display panel giant
BOE
has been flooded with articles supported by Liu Shuwei. Let's follow the embedded editor to learn about the relevant content.
...[Details]
In the actual project development process, it is common to encounter modifications to the hardware circuit, and then the modified part requires the modification of the driver. Thinking about the comi...[Details]
Unique device identifiers are suitable for: ● Used as a serial number (e.g. USB string serial number or other terminal applications) ● Use the unique ID as a security key when used in conjunction wit...[Details]
Friends who work in the photovoltaic industry, do you still remember the hard work on June 30 last year? How many people worked late into the night for months in a row just to connect to the grid a...[Details]
Serial Port: 一. USART_ITConfig(USART1, USART_IT_TXE, ENABLE): As long as the transmit register is empty, there will always be an interrupt. Therefore, if you are not sending data, turn off the tran...[Details]
1. Basic Concepts of LCD/LCM The structure of Liquid Crystal Display (LCD) is to place liquid crystals between two parallel pieces of glass. There are many vertical and horizontal fine wires between...[Details]
1. Initial understanding of FSMC: FSMC consists of 4 modules: (1) AHB interface (including FSMC configuration register) (2) NOR flash memory and PSRAM controller (when driving LCD, LCD is like a PSRA...[Details]
Overview
Lightning is a strong discharge phenomenon that occurs between thunderstorm clouds and between thunderstorm clouds and the earth due to severe convective weather. Lightning is gen...[Details]
I slightly changed the lyrics of Yu Quan's song "Running", which seems to be
a reflection of the current state of
Huawei Cloud
. At the annual Huawei Analyst Conference held on April 17,
Zh...[Details]
Unlike three years ago, today's
artificial intelligence
is no longer just a floating concept, and the venture capital circle has begun to explore the various possibilities of this technolog...[Details]
This paper combines embedded control technology with network control technology to realize the design of temperature control system based on single chip microcomputer through Internet control. Th...[Details]
Ouster LiDAR OS-1 (left) and OS-2 (center) Velodyne invented the modern 3D LiDAR scanner in the mid-2000s, but in recent years conventional wisdom has held that Velodyne’s design — 64 lasers mounted...[Details]
Summary of STM32 peripheral DMA usage: 1. Select DAM mode according to your needs: (1) Circular mode—DMA_Mode = DMA_Mode_Circular (2) Normal mode—DMA_Mode = DMA_Mode_Normal 2. For Chanel3 of DMA1, t...[Details]
This program sets the LED running light and the 0-16 numbers of the 0th position of the digital tube to light up in a cycle. The digital tube program cannot be put into the main function, because the...[Details]
Embedded System
京公网安备 11010802033920号
EEWORLD
