参数资料
型号: LT1683EG
厂商: LINEAR TECHNOLOGY CORP
元件分类: 稳压器
英文描述: Ultralow Noise Push-Pull DC/DC Controller
中文描述: SWITCHING CONTROLLER, 250 kHz SWITCHING FREQ-MAX, PDSO20
封装: 5.30 MM, PLASTIC, SSOP-20
文件页数: 7/24页
文件大小: 237K
代理商: LT1683EG
7
LT1683
1683f
Gate Drive
GATE A, GATE B (Pins 1, 19):
These pins connect to the
gates of the external N-channel MOSFETs. GATEA and
GATEB turn on with alternate clock cycles. These drivers
are capable of sinking and sourcing at least 300mA.
The GCL pin sets the upper voltage of the gate drive. The
gate pins will not be activated until V
IN
reaches a minimum
voltage as defined by the GCL pin (gate undervoltage
lockout).
The gate drive outputs have current limit protection to safe
guard against accidental shorts.
If the gate drive voltage is greater than about 1V the
opposite gate drive is inhibited thus preventing cross
conduction.
GCL (Pin 3):
This pin sets the maximum gate voltage to the
GATEA and GATEB pins to the MOSFET gate drives. This
pin should be either tied to a Zener, a voltage source or V
IN
.
If the pin is tied to a Zener or a voltage source, the
maximum gate drive voltage will be approximately
V
GCL
– 0.2V. If it is tied to V
IN
, the maximum gate voltage
is approximately V
IN
– 1.6.
Approximately 50
μ
A of current can be sourced from this
pin if V
GCL
< V
IN
– 0.8V.
This pin also controls undervoltage lockout of the gate
drives. If the pin is tied to a Zener or voltage source, the
gate drive will not be enabled until V
IN
> V
GCL
+ 0.8V. If this
pin is tied to V
IN
, then undervoltage lockout is disabled.
There is an internal 19V Zener tied from this pin to ground
to provide a fail-safe for maximum gate voltage.
Slew Control
CAP A, CAP B (Pins 2, 18):
These pins are the feedback
nodes for the external voltage slewing capacitors. Nor-
mally a small 1pf to 5pf capacitor is connected from this
pin to the drain of its respective MOSFET.
The voltage slew rate is inversely proportional to this
capacitance and proportional to the current that the part
will sink and source on this pin. That current is inversely
proportional to R
VSL
.
R
CSL
(Pin 15):
A resistor to ground sets the current slew
rate for the external drive MOSFETs during switching. The
minimum resistor value is 3.3k and the maximum value is
68k. The time to slew between on and off states of the
MOSFET current will determine how the di/dt related
harmonics are reduced. This time is proportional to R
CSL
and R
S
(the current sense resistor) and maximum current.
Longer times produce a greater reduction of higher fre-
quency harmonics.
R
VSL
(Pin 16):
A resistor to ground sets the voltage slew
rate for the drains of the external drive MOSFETs. The
minimum resistor value is 3.3k and the maximum value is
68k. The time to slew between on and off states on the
MOSFET drain voltage will determine how harmonics are
reduced from this source. This time is proportional to
R
VSL
, C
VA/B
and the input voltage. Longer times produce
more rolloff of harmonics. C
VA/B
is the equivalent capaci-
tance from CAP A or B to the drain of the MOSFET.
Switch Mode Control
SS (Pin 3):
The SS pin allows for ramping of the switch
current threshold at startup. Normally a capacitor is placed
on this pin to ground. An internal 9
μ
A current source will
charge this capacitor up. The voltage on the V
C
pin cannot
exceed the voltage on SS. Thus peak current will ramp up
as the SS pin ramps up. During a short circuit fault the SS
pin will be discharged to ground thus reinitializing soft-
start.
When SS is below the V
C
clamp voltage the V
C
pin will
closely track the SS pin.
This pin can be left open if not used.
PIU
相关PDF资料
PDF描述
LT1719CS6 4.5ns Single/Dual Supply 3V/5V Comparator with Rail-to-Rail Output
LT1719IS6 4.5ns Single/Dual Supply 3V/5V Comparator with Rail-to-Rail Output
LT1721CS Dual/Quad, 4.5ns, Single Supply 3V/5V Comparators with Rail-to-Rail Outputs
LT1721IGN Dual/Quad, 4.5ns, Single Supply 3V/5V Comparators with Rail-to-Rail Outputs
LT1720IS8 Dual/Quad, 4.5ns, Single Supply 3V/5V Comparators with Rail-to-Rail Outputs
相关代理商/技术参数
参数描述
LT1683EG#PBF 功能描述:IC REG CTRLR PWM CM 20-SSOP RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:- 特色产品:LM3753/54 Scalable 2-Phase Synchronous Buck Controllers 标准包装:1 系列:PowerWise® PWM 型:电压模式 输出数:1 频率 - 最大:1MHz 占空比:81% 电源电压:4.5 V ~ 18 V 降压:是 升压:无 回扫:无 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:无 工作温度:-5°C ~ 125°C 封装/外壳:32-WFQFN 裸露焊盘 包装:Digi-Reel® 产品目录页面:1303 (CN2011-ZH PDF) 其它名称:LM3754SQDKR
LT1683EG#TR 功能描述:IC REG CTRLR PWM CM 20-SSOP RoHS:否 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:- 标准包装:4,500 系列:PowerWise® PWM 型:控制器 输出数:1 频率 - 最大:1MHz 占空比:95% 电源电压:2.8 V ~ 5.5 V 降压:是 升压:无 回扫:无 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:无 工作温度:-40°C ~ 125°C 封装/外壳:6-WDFN 裸露焊盘 包装:带卷 (TR) 配用:LM1771EVAL-ND - BOARD EVALUATION LM1771 其它名称:LM1771SSDX
LT1683EG#TRPBF 功能描述:IC REG CTRLR PWM CM 20-SSOP RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:- 标准包装:4,500 系列:PowerWise® PWM 型:控制器 输出数:1 频率 - 最大:1MHz 占空比:95% 电源电压:2.8 V ~ 5.5 V 降压:是 升压:无 回扫:无 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:无 工作温度:-40°C ~ 125°C 封装/外壳:6-WDFN 裸露焊盘 包装:带卷 (TR) 配用:LM1771EVAL-ND - BOARD EVALUATION LM1771 其它名称:LM1771SSDX
LT1683IG 功能描述:IC REG CTRLR PWM CM 20-SSOP RoHS:否 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:- 标准包装:4,500 系列:PowerWise® PWM 型:控制器 输出数:1 频率 - 最大:1MHz 占空比:95% 电源电压:2.8 V ~ 5.5 V 降压:是 升压:无 回扫:无 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:无 工作温度:-40°C ~ 125°C 封装/外壳:6-WDFN 裸露焊盘 包装:带卷 (TR) 配用:LM1771EVAL-ND - BOARD EVALUATION LM1771 其它名称:LM1771SSDX
LT1683IG#PBF 功能描述:IC REG CTRLR PWM CM 20-SSOP RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:- 标准包装:4,500 系列:PowerWise® PWM 型:控制器 输出数:1 频率 - 最大:1MHz 占空比:95% 电源电压:2.8 V ~ 5.5 V 降压:是 升压:无 回扫:无 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:无 工作温度:-40°C ~ 125°C 封装/外壳:6-WDFN 裸露焊盘 包装:带卷 (TR) 配用:LM1771EVAL-ND - BOARD EVALUATION LM1771 其它名称:LM1771SSDX