- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄379176 > DS1094L 10/100/1000 Base-T Ethernet LAN Switch PDF資料下載
參數(shù)資料
| 型號(hào)： | DS1094L |
| 英文描述： | 10/100/1000 Base-T Ethernet LAN Switch |
| 中文描述： | 多相擴(kuò)頻EconOscillator |
| 文件頁數(shù)： | 7/11頁 |
| 文件大?。?/td> | 590K |
| 代理商： | DS1094L |
Prescaler
The prescaler divides the master oscillator frequency,
f
MOSC
, by 1, 2, 4, or 8. The resultant frequency, f
OSC
, is
calculated using the following formula:
f
OSC
= f
MOSC
/ 2
PRESCALER
where PRESCALER can be 0 to 3. The prescaler is con-
figured using bits P1 and P0 in the PRESCALER regis-
ter. Valid settings are shown in Table 2. The location of
bits P1 and P0 in the PRESCALER register is shown in
the
Control Registers
section.
Note that the PRESCALER register also contains bits
controlling other features of the device (dither amount,
dither rate, and phase).
Phase Generator
The four oscillator outputs (OUT1 to OUT4) can be con-
figured in either two-phase, three-phase, or four-phase
mode. The output waveforms of each mode are illus-
trated in Figure 1. Likewise, the figure also shows a
comparison of f
OUT
, the duty cycle, and the output
phase shifts between the three modes. Bits Ph1 and
Ph0 in the PRESCALER register are used to select the
desired mode (see Table 3). The location of bits Ph1
and Ph0 in the PRESCALER register is shown in the
Control Registers section.
Triangle Wave Generator
The triangle wave generator is used to dither the mas-
ter oscillator frequency, adding spread-spectrum func-
tionality to the DS1094L by injecting an offset element
into the master oscillator. Both the dither amount (%)
and dither frequency are programmable. The dither
amount is controlled by bits J1 and J0 in the
PRESCALER register. The dither frequency is con-
trolled by bits D1 and D0, also in the PRESCALER reg-
ister. The bit settings are shown in Table 4 and 5. The
location of bits J1, J0, D1, and D0 in the PRESCALER
register is shown in the
Control Registers
section.
When dither is enabled (by selecting a percentage
other than 0%), the master oscillator frequency, f
MOSC
,
is dithered between the programmed f
MOSC
and the
selected percentage down from the programmed
f
MOSC
(see Figure 2). For example, if f
MOSC
is pro-
grammed to 2MHz (DAC register = 0Ah) and the dither
amount is programmed to 2%, the frequency of f
MOSC
D
Multiphase Spread-Spectrum EconOscillator
_____________________________________________________________________
7
BITS Ph1, Ph0
00
01
10
11
MODE
Two-Phase
Three-Phase
Four-Phase
Reserved
Table 3. Phase Generator Settings
BITS J1, J0
00
01
10
11
DITHER AMOUNT*
0%
2%
4%
8%
Table 4. Dither Amount Settings
BITS D1, D0
00
01
10
11
DITHER FREQUENCY
f
MOSC
/128
f
MOSC
/256
f
MOSC
/512
f
MOSC
/1024
Table 5. Dither Frequency Settings
OUT1
OUT2
OUT3
OUT4
OUT1
OUT2
OUT3
OUT4
OUT1
OUT2
OUT3
OUT4
f
OSC
TWO-PHASE
THREE-PHASE
FOUR-PHASE
50% DUTY CYCLE
50% DUTY CYCLE
90 DEGREES OUT
OF PHASE
33% DUTY CYCLE
120 DEGREES
OUT OF PHASE
180 DEGREES
OUT OF PHASE
f
OUT
= f
OSC
f
OUT
= f
OSC
/ 3
f
OUT
= f
OSC
/ 4
Figure 1. DS1094L Output Waveforms
TIME
1
DITHER FREQ.
PROGRAMMED f
MOSC
PROGRAMMED f
MOSC
-
(2, 4, OR 8% OF f
MOSC
)
DITHER
AMOUNT
(2, 4, OR 8%)
IF DITHER AMOUNT = 0%
f
M
Figure 2. DS1094L Dither Waveform
*
The frequency is dithered down from the programmed value
of f
MOSC
.
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| DS1094LU | Multiphase Spread-Spectrum EconOscillator |
| DS1099 | Low-Frequency Dual EconOscillator |
| DS1099U | Space-Saving, 8-Channel Relay/Load Driver |
| DS1104SG25 | Rectifier Diode |
| DS1104SG26 | Rectifier Diode |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| DS1094LU-350+ | 制造商:Maxim Integrated Products 功能描述: |
| DS1094LU-42M | 功能描述:可編程振蕩器 Multiphase Spread Spctrm EconOscillatr RoHS:否 制造商:IDT 封裝 / 箱體:5 mm x 7 mm x 1.5 mm 頻率:15.476 MHz to 866.67, 975 MHz to 1300 MHz 頻率穩(wěn)定性:+/- 50 PPM 電源電壓:3.63 V 負(fù)載電容:10 pF 端接類型:SMD/SMT 輸出格式:LVPECL 最小工作溫度:- 40 C 最大工作溫度:+ 85 C 尺寸:7 mm W x 5 mm L x 1.5 mm H 封裝: |
| DS1094LU-42M+ | 功能描述:可編程振蕩器 Multiphase Spread Spctrm EconOscillatr RoHS:否 制造商:IDT 封裝 / 箱體:5 mm x 7 mm x 1.5 mm 頻率:15.476 MHz to 866.67, 975 MHz to 1300 MHz 頻率穩(wěn)定性:+/- 50 PPM 電源電壓:3.63 V 負(fù)載電容:10 pF 端接類型:SMD/SMT 輸出格式:LVPECL 最小工作溫度:- 40 C 最大工作溫度:+ 85 C 尺寸:7 mm W x 5 mm L x 1.5 mm H 封裝: |
| DS1094LU-42M+T | 功能描述:可編程振蕩器 Multiphase Spread Spctrm EconOscillatr RoHS:否 制造商:IDT 封裝 / 箱體:5 mm x 7 mm x 1.5 mm 頻率:15.476 MHz to 866.67, 975 MHz to 1300 MHz 頻率穩(wěn)定性:+/- 50 PPM 電源電壓:3.63 V 負(fù)載電容:10 pF 端接類型:SMD/SMT 輸出格式:LVPECL 最小工作溫度:- 40 C 最大工作溫度:+ 85 C 尺寸:7 mm W x 5 mm L x 1.5 mm H 封裝: |
| DS1099U-01M | 功能描述:可編程振蕩器 Low-Frequency Dual EconOscillator RoHS:否 制造商:IDT 封裝 / 箱體:5 mm x 7 mm x 1.5 mm 頻率:15.476 MHz to 866.67, 975 MHz to 1300 MHz 頻率穩(wěn)定性:+/- 50 PPM 電源電壓:3.63 V 負(fù)載電容:10 pF 端接類型:SMD/SMT 輸出格式:LVPECL 最小工作溫度:- 40 C 最大工作溫度:+ 85 C 尺寸:7 mm W x 5 mm L x 1.5 mm H 封裝: |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。