參數(shù)資料
型號(hào): DS1086LU-21D+T
廠商: Maxim Integrated Products
文件頁(yè)數(shù): 4/17頁(yè)
文件大小: 0K
描述: IC ECONOSCILLATOR SS 8-USOP
其它有關(guān)文件: Automotive Product Guide
產(chǎn)品培訓(xùn)模塊: Lead (SnPb) Finish for COTS
Obsolescence Mitigation Program
標(biāo)準(zhǔn)包裝: 3,000
系列: EconOscillator™
類(lèi)型: 擴(kuò)展頻譜時(shí)鐘發(fā)生器
PLL: 無(wú)
輸入: 時(shí)鐘
輸出: 時(shí)鐘
電路數(shù): 1
比率 - 輸入:輸出: 2:1
差分 - 輸入:輸出: 無(wú)/無(wú)
除法器/乘法器: 是/無(wú)
電源電壓: 2.7 V ~ 3.6 V
工作溫度: -40°C ~ 85°C
安裝類(lèi)型: 表面貼裝
封裝/外殼: 8-TSSOP,8-MSOP(0.118",3.00mm 寬)
供應(yīng)商設(shè)備封裝: 8-uMAX
包裝: 帶卷 (TR)
3.3V Spread-Spectrum EconOscillator
12
Maxim Integrated
DS1086L
Example Frequency Calculations
Example #1:
Calculate the register values needed to
generate a desired output frequency of 11.0592MHz.
Since the desired frequency is not within the valid mas-
ter oscillator range of 33.3MHz to 66.6MHz, the
prescaler must be used. Valid prescaler values are 2x
where x equals 0 to 8 (and x is the value that is pro-
grammed into the P3 to P0 bits of the PRESCALER reg-
ister). Equation 1 shows the relationship between the
desired frequency, the master oscillator frequency, and
the prescaler.
By trial and error, x is incremented from 0 to 8 in
Equation 2, finding values of x that yield master oscillator
frequencies within the range of 33.3MHz to 66.6MHz.
Equation 2 shows that a prescaler of 4 (x = 2) and a
master oscillator frequency of 44.2368MHz generates
our desired frequency. Writing 0080h to the
PRESCALER register sets the PRESCALER to 4. Be
aware that other settings also reside in the PRESCALER
register.
fMASTER OSCILLATOR = fDESIRED x prescaler = fDESIRED x 2X
fMASTER OSCILLATOR = 11.0592MHz x 22 = 44.2368MHz
Once the target master oscillator frequency has been
calculated, the value of offset can be determined.
Using Table 2, 44.2368MHz falls within both OS - 1 and
OS - 2. However, choosing OS - 1 would be a poor
choice since 44.2368MHz is so close to OS - 1’s mini-
mum frequency. On the other hand, OS - 2 is ideal
since 44.2368MHz is close to the center of
OS - 2’s frequency span. Before the OFFSET register
can be programmed, the default value of offset (OS)
must be read from the RANGE register (last five bits). In
this example, 12h (18 decimal) was read from the
RANGE register. OS - 2 for this case is 10h (16 deci-
mal). This is the value that is written to the OFFSET reg-
ister.
Finally, the two-byte DAC value needs to be deter-
mined. Since OS - 2 only sets the range of frequencies,
the DAC selects one frequency within that range as
shown in Equation 3.
fMASTER OSCILLATOR = (MIN FREQUENCY OF SELECTED OFFSET
RANGE) + (DAC value x 5kHz)
Valid values of DAC are 0 to 1023 (decimal) and 5kHz
is the step size. Equation 4 is derived from rearranging
Equation 3 and solving for the DAC value.
Since the two-byte DAC register is left justified, 647 is
converted to hex (0287h) and bit-wise shifted left six
places. The value to be programmed into the DAC reg-
ister is A1C0h.
In summary, the DS1086L is programmed as follows:
PRESCALER = 0080h
OFFSET = OS - 2 or 10h (if range was read as 12h)
DAC = A1C0h
Notice that the DAC value was rounded. Unfortunately,
this means that some error is introduced. To calculate
how much error, a combination of Equation 1 and
Equation 3 is used to calculate the expected output fre-
quency. See Equation 5.
f
MIN FREQUENCY OF SELECTED OFFSET
OUTPUT
(
=
)(
)
RANGE
DAC VALUE x kHz STEP SIZE
pres
+
5
c
caler
f
MHz
x kHz
OUTPUT
(.
)
(
)
=
+
41 0
647
5
4
==
=
.
44 235
4
11 05875
MHz
DAC VALUE
f
MIN FREQU
MASTER OSCILLATOR
(
=
E
ENCY OF SELECTED
OFFSET RANGE
kHz STEP SI
)
5
Z
ZE
DAC VALUE
MHz
kHz S
(.
.
)
=
44 2368
41 0
5
T
TEP SIZE
decimal
.(
)
=≈
647 36
647
f
prescaler
f
DESIRED
MASTER OSCILLATOR
M
=
A
ASTER OSCILLATOR
X
2
(1)
(4)
(2)
(3)
(5)
相關(guān)PDF資料
PDF描述
DS1086LU-533+T IC ECONOSCILLATOR SS 8-USOP
MCP4912-E/P DAC 10BIT DUAL W/SPI 14PDIP
VI-B0K-MY-F1 CONVERTER MOD DC/DC 40V 50W
VI-2VT-MY-F2 CONVERTER MOD DC/DC 6.5V 50W
MCP4912-E/ST DAC 10BIT DUAL W/SPI 14TSSOP
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
DS1086LU-222+ 功能描述:可編程振蕩器 SS OSC 22.1184Mhz 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(lèi)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:
DS1086LU-222+T 功能描述:可編程振蕩器 SS OSC 22.1184Mhz 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(lèi)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:
DS1086LU-40S+ 功能描述:可編程振蕩器 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(lèi)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:
DS1086LU-40S+T 功能描述:可編程振蕩器 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(lèi)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:
DS1086LU-440/V+ 功能描述:可編程振蕩器 3.3V Spread-Spectrum 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(lèi)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: