參數(shù)資料
型號: LTC1422IS8#PBF
廠商: LINEAR TECHNOLOGY CORP
元件分類: 電源管理
英文描述: Hot Swap Controller; Package: SO; No of Pins: 8; Temperature Range: -40°C to +85°C
中文描述: 1-CHANNEL POWER SUPPLY SUPPORT CKT, PDSO8
封裝: 0.150 INCH, PLASTIC, SO-8
文件頁數(shù): 3/16頁
文件大?。?/td> 193K
代理商: LTC1422IS8#PBF
11
LTC1422
1422fb
plus a Zener voltage (D1) is more positive than the drain
of Q1 (in other words, when the switching FET Q1 has only
7.5V across its drain source).
Hot Swapping 48V Module with Isolated Controller
A power supervisory controller will sometimes reside on
an isolated supply with responsibility for other supplies.
Figure 15 shows how to Hot Swap a controller’s 5V supply
and a 48V module using two LTC1422s. Assuming the 5V
supply comes up first, the controller waits for a power
good signal from the 48V circuit. Once it receives the right
signals the controller activates the GATE IN pin of the Vicor
power module.
Power Supply Sequencer
A circuit that forces two supply voltages to power up
together is shown in Figure 16. The input supply voltages
may power up in any sequence, but both input voltages
must be within tolerance before Q1 and Q2 turn on. Back-
to-back transistors Q1 and Q2 ensure isolation between
the two supplies.
When the 5V input powers up before 3.3V, Q1 and Q2
remain off and the 5V output remains off until the 3.3V
input is within tolerance as sensed by resistors R1 and R2.
When the 3.3V input powers up before 5V, the diode D1
will pull up the 5V supply output with it. Once the 5V input
powers up and is within tolerance as sensed by R4 and R5,
Q1 and Q2 will turn on in about 1ms and pull the 5V output
up to its final voltage.
Since the pass transistor is in a common source configu-
ration, care must be taken to limit the inrush current into
capacitor C3. One way is to precharge C3 using resistor
R4. As the input supply is ramping up, current is flowing
through R4 and charging the capacitor C3. Once the input
supply crosses 38V, there is a timing cycle followed by the
ramp-up of the GATE pin. By this time the capacitor C3 is
sufficiently charged, thereby limiting the inrush current.
Another method to limit the inrush current is to slow down
the ramp-up rate of the GATE pin.
Hot Swapping 48V DC/DC Module with
Active High On/Off Control Signal
This application is identical to the previous except for the
polarity of the module’s on/off signal. The polarity reversal
is accomplished by transistor Q3 in Figure 13.
Hot Swapping Redundant 48V
In critical situations, redundant input supplies are neces-
sary. In Figure 14 a redundant 48V input is switched to a
power module. Supplies 1 and 2 are wire OR’ed using two
diodes D2 and D3. This results in the most negative of
these two supplies being used to drive the power module.
If one of the supplies is disconnected or a fuse opens, the
fault signal will be activated via diodes D4 and D5 and the
reset comparator at the FB pin. The GATE IN signal on the
Vicor module is controlled using the high voltage PNP Q2.
Once the module’s minus input pin is more negative than
the base of Q2 plus a diode drop, Q2 will turn off and the
module will turn on. This occurs when the source of Q1
1
2
3
4
8
7
6
5
VCC
SENSE
GATE
FB
RESET
ON
TIMER
GND
LTC1422
1422 F11
Q1
MMFT2N02ELT1
CURRENT LIMIT: 2.5A
Q2
MMFT2N02ELT1
R1
0.02
5%
R3
10
5%
R6
1.6M
5%
R7
360k
5%
R2
10
5%
R4
2.74k
1%
R5
1.62k
1%
Q3
PN2222
C1
0.0033
F
16V
C2
0.1
F
16V
CLOAD
C3
0.1
F
16V
CLOAD
VOUT
3.3V
VOUT
5V
VIN
5V
+
Figure 11. Switching 5V and Generating 3.3V
APPLICATIONS INFORMATION
WU
U
相關PDF資料
PDF描述
LTC1422IS8#TRPBF Hot Swap Controller; Package: SO; No of Pins: 8; Temperature Range: -40°C to +85°C
LTC1426CMS8#PBF Micropower Dual 6-Bit PWM DAC; Package: MSOP; No of Pins: 8; Temperature Range: 0°C to +70°C
LTC1426CMS8#TRPBF Micropower Dual 6-Bit PWM DAC; Package: MSOP; No of Pins: 8; Temperature Range: 0°C to +70°C
LTC1426CS8#PBF Micropower Dual 6-Bit PWM DAC; Package: SO; No of Pins: 8; Temperature Range: 0°C to +70°C
LTC1426CS8#TRPBF Micropower Dual 6-Bit PWM DAC; Package: SO; No of Pins: 8; Temperature Range: 0°C to +70°C
相關代理商/技術參數(shù)
參數(shù)描述
LTC1426CMS8 功能描述:IC PWM D/A CONV 6BIT DUAL 8-MSOP RoHS:否 類別:集成電路 (IC) >> 數(shù)據(jù)采集 - 數(shù)模轉換器 系列:- 產品培訓模塊:LTC263x 12-, 10-, and 8-Bit VOUT DAC Family 特色產品:LTC2636 - Octal 12-/10-/8-Bit SPI VOUT DACs with 10ppm/°C Reference 標準包裝:91 系列:- 設置時間:4µs 位數(shù):10 數(shù)據(jù)接口:MICROWIRE?,串行,SPI? 轉換器數(shù)目:8 電壓電源:單電源 功率耗散(最大):2.7mW 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:14-WFDFN 裸露焊盤 供應商設備封裝:14-DFN-EP(4x3) 包裝:管件 輸出數(shù)目和類型:8 電壓,單極 采樣率(每秒):*
LTC1426CMS8#PBF 功能描述:IC PWM D/A CONV 6BIT DUAL 8-MSOP RoHS:是 類別:集成電路 (IC) >> 數(shù)據(jù)采集 - 數(shù)模轉換器 系列:- 標準包裝:2,400 系列:- 設置時間:- 位數(shù):18 數(shù)據(jù)接口:串行 轉換器數(shù)目:3 電壓電源:模擬和數(shù)字 功率耗散(最大):- 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:36-TFBGA 供應商設備封裝:36-TFBGA 包裝:帶卷 (TR) 輸出數(shù)目和類型:* 采樣率(每秒):*
LTC1426CMS8#TR 功能描述:IC DAC PWM 6BIT DUAL MCPWR 8MSOP RoHS:否 類別:集成電路 (IC) >> 數(shù)據(jù)采集 - 數(shù)模轉換器 系列:- 產品培訓模塊:LTC263x 12-, 10-, and 8-Bit VOUT DAC Family 特色產品:LTC2636 - Octal 12-/10-/8-Bit SPI VOUT DACs with 10ppm/°C Reference 標準包裝:91 系列:- 設置時間:4µs 位數(shù):10 數(shù)據(jù)接口:MICROWIRE?,串行,SPI? 轉換器數(shù)目:8 電壓電源:單電源 功率耗散(最大):2.7mW 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:14-WFDFN 裸露焊盤 供應商設備封裝:14-DFN-EP(4x3) 包裝:管件 輸出數(shù)目和類型:8 電壓,單極 采樣率(每秒):*
LTC1426CMS8#TRPBF 功能描述:IC PWM D/A CONV 6BIT DUAL 8-MSOP RoHS:是 類別:集成電路 (IC) >> 數(shù)據(jù)采集 - 數(shù)模轉換器 系列:- 標準包裝:2,400 系列:- 設置時間:- 位數(shù):18 數(shù)據(jù)接口:串行 轉換器數(shù)目:3 電壓電源:模擬和數(shù)字 功率耗散(最大):- 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:36-TFBGA 供應商設備封裝:36-TFBGA 包裝:帶卷 (TR) 輸出數(shù)目和類型:* 采樣率(每秒):*
LTC1426CS8 功能描述:IC PWM D/A CONV 6BIT DUAL 8-SOIC RoHS:否 類別:集成電路 (IC) >> 數(shù)據(jù)采集 - 數(shù)模轉換器 系列:- 產品培訓模塊:LTC263x 12-, 10-, and 8-Bit VOUT DAC Family 特色產品:LTC2636 - Octal 12-/10-/8-Bit SPI VOUT DACs with 10ppm/°C Reference 標準包裝:91 系列:- 設置時間:4µs 位數(shù):10 數(shù)據(jù)接口:MICROWIRE?,串行,SPI? 轉換器數(shù)目:8 電壓電源:單電源 功率耗散(最大):2.7mW 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:14-WFDFN 裸露焊盤 供應商設備封裝:14-DFN-EP(4x3) 包裝:管件 輸出數(shù)目和類型:8 電壓,單極 采樣率(每秒):*