參數(shù)資料
型號(hào)： COP8SGF940Q7
廠商： National Semiconductor Corporation
英文描述： 8-Bit CMOS ROM Based and OTP Microcontrollers with 8k to 32k Memory, Two Comparators and USART
中文描述： 8位的CMOS基于ROM和OTP微控制器具有8K到32K的內(nèi)存，2個(gè)比較器和USART
文件頁(yè)數(shù)： 20/62頁(yè)
文件大?。?/td> 913K
代理商： COP8SGF940Q7
5.0 Functional Description
(Continued)
5.10 OSCILLATOR CIRCUITS
There are four clock oscillator options available: Crystal
Oscillator with or without on-chip bias resistor, R/C Oscillator
with on-chip resistor and capacitor, and External Oscillator.
The oscillator feature is selected by programming the ECON
register, which is summarized in Table 1
TABLE 1. Oscillator Option
ECON4
0
1
0
1
ECON3
0
0
1
1
Oscillator Option
External Oscillator
Crystal Oscillator without Bias Resistor
R/C Oscillator
Crystal Oscillator with Bias Resistor
5.10.1 Crystal Oscillator
The crystal Oscillator mode can be selected by programming
ECON Bit 4 to 1. CKI is the clock input while G7/CKO is the
clock generator output to the crystal. An on-chip bias resistor
connected between CKI and CKO can be enabled by pro-
gramming ECON Bit 3 to 1 with the crystal oscillator option
selection. The value of the resistor is in the range of 0.5M to
2M (typically 1.0M). Table 2 shows the component values
required for various standard crystal values. Resistor R2 is
only used when the on-chip bias resistor is disabled. Figure
12 shows the crystal oscillator connection diagram.
TABLE 2. Crystal Oscillator Configuration,
T
A
= 25C, V
CC
= 5V
R1 (k
)
R2 (M
)
C1 (pF)
C2 (pF)
CKI Freq.
(MHz)
15
10
4
0.455
0
0
0
1
1
1
1
18
20
25
100
18
20
25
5.6
100–156
5.10.2 External Oscillator
The External Oscillator mode can be selected by program-
ming ECON Bit 3 to 0 and ECON Bit 4 to 0. CKI can be
driven by an external clock signal provided it meets the
specified duty cycle, rise and fall times, and input levels.
G7/CKO is available as a general purpose input G7 and/or
Halt control. Figure 13 shows the external oscillator connec-
tion diagram.
5.10.3 R/C Oscillator
The R/C Oscillator mode can be selected by programming
ECON Bit 3 to 1 and ECON Bit 4 to 0. In R/C oscillation
mode, CKI is left floating, while G7/CKO is available as a
general purpose input G7 and/or HALT control. The R/C
controlled oscillator has on-chip resistor and capacitor for
maximum R/C oscillator frequency operation. The maximum
frequency is 5 MHz
±
35% for V
between 4.5V to 5.5V
and temperature range of 40C to +85C. For max fre-
quency operation, the CKI pin should be left floating. For
lower frequencies, an external capacitor should be con-
nected between CKI and either V
or GND. Immunity of the
R/C oscillator to external noise can be improved by connect-
ing one half the external capacitance to V
and one half to
GND. PC board trace length on the CKI pin should be kept
as short as possible. Table 3 shows the oscillator frequency
as a function of external capacitance on the CKI pin. Figure
14 shows the R/C oscillator configuration.
TABLE 3. R/C Oscillator Configuration,
40C to +85C, V
= 4.5V to 5.5V,
OSC Freq. Variation of
±
35%
External
Capacitor (pF)*
0
9
52
125
6100
* Assumes 3-5 pF board capacitance.
R/C OSC Freq
(MHz)
5
4
2
1
32 kHz
Instr. Cycle (μs)
2.0
2.5
5.0
10
312.5
With On-Chip Bias Resistor
Without On-Chip Bias Resistor
10131717
10131718
FIGURE 12. Crystal Oscillator
C
www.national.com
20
相關(guān)PDF資料
PDF描述
COP8SGF940Q8 8-Bit CMOS ROM Based and OTP Microcontrollers with 8k to 32k Memory, Two Comparators and USART
COP8SGF940Q9 8-Bit CMOS ROM Based and OTP Microcontrollers with 8k to 32k Memory, Two Comparators and USART
COP8SGF940V3 8-Bit CMOS ROM Based and OTP Microcontrollers with 8k to 32k Memory, Two Comparators and USART
COP8SGF940V6 CAP CERAMIC 1.1PF 25V C0G 0201
COP8SGF940V7 CAP CERAMIC 1.2PF 25V C0G 0201
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
COP8SGR728M7 功能描述:8位微控制器 -MCU RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數(shù)據(jù)總線寬度:8 bit 最大時(shí)鐘頻率:50 MHz 程序存儲(chǔ)器大小:16 KB 數(shù)據(jù) RAM 大小:1 KB 片上 ADC:Yes 工作電源電壓:1.8 V to 3.6 V 工作溫度范圍:- 40 C to + 105 C 封裝 / 箱體:QFN-20 安裝風(fēng)格:SMD/SMT
COP8SGR728M7/NOPB 功能描述:8位微控制器 -MCU RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數(shù)據(jù)總線寬度:8 bit 最大時(shí)鐘頻率:50 MHz 程序存儲(chǔ)器大小:16 KB 數(shù)據(jù) RAM 大小:1 KB 片上 ADC:Yes 工作電源電壓:1.8 V to 3.6 V 工作溫度范圍:- 40 C to + 105 C 封裝 / 箱體:QFN-20 安裝風(fēng)格:SMD/SMT
COP8SGR728M8 功能描述:8位微控制器 -MCU RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數(shù)據(jù)總線寬度:8 bit 最大時(shí)鐘頻率:50 MHz 程序存儲(chǔ)器大小:16 KB 數(shù)據(jù) RAM 大小:1 KB 片上 ADC:Yes 工作電源電壓:1.8 V to 3.6 V 工作溫度范圍:- 40 C to + 105 C 封裝 / 箱體:QFN-20 安裝風(fēng)格:SMD/SMT
COP8SGR728M8/NOPB 功能描述:8位微控制器 -MCU RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數(shù)據(jù)總線寬度:8 bit 最大時(shí)鐘頻率:50 MHz 程序存儲(chǔ)器大小:16 KB 數(shù)據(jù) RAM 大小:1 KB 片上 ADC:Yes 工作電源電壓:1.8 V to 3.6 V 工作溫度范圍:- 40 C to + 105 C 封裝 / 箱體:QFN-20 安裝風(fēng)格:SMD/SMT
COP8SGR728N8 功能描述:8位微控制器 -MCU RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數(shù)據(jù)總線寬度:8 bit 最大時(shí)鐘頻率:50 MHz 程序存儲(chǔ)器大小:16 KB 數(shù)據(jù) RAM 大小:1 KB 片上 ADC:Yes 工作電源電壓:1.8 V to 3.6 V 工作溫度范圍:- 40 C to + 105 C 封裝 / 箱體:QFN-20 安裝風(fēng)格:SMD/SMT
發(fā)布緊急采購(gòu)，3分鐘左右您將得到回復(fù)。

采購(gòu)需求

(若只采購(gòu)一條型號(hào)，填寫一行即可)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

*型號(hào) *數(shù)量 廠商 批號(hào) 封裝
添加更多采購(gòu)

我的聯(lián)系方式

*
*
*