- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄10198 > SP3239EEA-L/TR (Exar Corporation)IC TXRX RS232 INTELLIGENT 28SSOP PDF資料下載
參數(shù)資料
| 型號： | SP3239EEA-L/TR |
| 廠商： | Exar Corporation |
| 文件頁數(shù)： | 16/16頁 |
| 文件大小： | 0K |
| 描述： | IC TXRX RS232 INTELLIGENT 28SSOP |
| 標準包裝： | 1,500 |
| 類型： | 收發(fā)器 |
| 驅(qū)動器/接收器數(shù)： | 5/3 |
| 規(guī)程： | RS232 |
| 電源電壓： | 3 V ~ 5.5 V |
| 安裝類型： | 表面貼裝 |
| 封裝/外殼： | 28-SSOP（0.209"，5.30mm 寬） |
| 供應商設備封裝： | 28-SSOP |
| 包裝： | 帶卷 (TR) |
Exar Corporation 48720 Kato Road, Fremont CA, 94538 510-668-7017 www.exar.com
SP3239E_100_020111
9
Phase 1
— V
SS charge storage — During this phase of the
clock cycle, the positive side of capacitors C
1 and
C
2 are initially charged to VCC. Cl
+
is then switched
to GND and the charge in C
1
–
is transferred to C
2
–
.
SinceC
2
+
isconnectedtoV
CC, the voltage potential
across capacitor C
2 is now 2 times VCC.
Phase 2
— V
SS transfer — Phase two of the clock
connects the negative terminal of C
2 to the VSS
storage capacitor and the positive terminal of
C
2 to GND.
This transfers a negative gener-
ated voltage to C
3. This generated voltage is
regulated to a minimum voltage of -5.5V.
SimultaneouswiththetransferofthevoltagetoC
3,
the positive side of capacitor C
1 is switched to VCC
and the negative side is connected to GND.
Phase 3
— V
DD charge storage — The third phase of the
clock is identical to the first phase — the charge
transferred in C
1 produces –VCC in the negative
terminal of C
1, which is applied to the negative
side of capacitor C
2. Since C2
+
is at V
CC, the volt-
age potential across C
2 is 2 times VCC.
Phase 4
— V
DD transfer — The fourth phase of the clock
connects the negative terminal of C
2 to GND,
and transfers this positive generated voltage
across C
2 to C4DD storage capacitor. This
voltage is regulated to +5.5V. At this voltage,
the internal oscillator is disabled. Simultane-
ous with the transfer of the voltage to C
4, the
positive side of capacitor C
1 is switched to VCC
and the negative side is connected to GND, al-
lowing the charge pump cycle to begin again.
The charge pump cycle will continue as long
as the operational conditions for the internal
oscillator are present.
Since both V+ and V– are separately generated
from V
CC, in a no–load condition V
+
and V– will
be symmetrical. Older charge pump approaches
that generate V– from V+ will show a decrease in
the magnitude of V– compared to V+ due to the
inherent inefficiencies in the design.
The clock rate for the charge pump typically
operates at 500kHz. The external capacitors
can be as low as 0.1F with a 16V breakdown
voltage rating.
Figure 10. Charge Pump Waveform
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| AD7859APZ | IC ADC 12BIT 8CH 200KSPS 44PLCC |
| MS3102E14S-2SY | CONN RCPT 4POS BOX MNT W/SCKT |
| ADM3222ARSZ-REEL | IC TXRX RS-232 3.3V W/SD 20SSOP |
| MS3102E14S-2SX | CONN RCPT 4POS BOX MNT W/SCKT |
| ADM3202ARWZ-REEL | IC TXRX DUAL RS-232 3.3V 16SOIC |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| SP3239EEY-L | 制造商:Rochester Electronics LLC 功能描述: 制造商:Exar Corporation 功能描述: |
| SP3243 | 制造商:SIPEX 制造商全稱:Sipex Corporation 功能描述:Intelligent +3.0V to +5.5V RS-232 Transceiver |
| SP3243B | 制造商:SIPEX 制造商全稱:Sipex Corporation 功能描述:Intelligent +3.0V to +5.5V RS-232 Transceivers |
| SP3243BCA | 制造商:SIPEX 制造商全稱:Sipex Corporation 功能描述:Intelligent +3.0V to +5.5V RS-232 Transceivers |
| SP3243BCR | 制造商:SIPEX 制造商全稱:Sipex Corporation 功能描述:Intelligent +3.0V to +5.5V RS-232 Transceivers |
發(fā)布緊急采購，3分鐘左右您將得到回復。