- 您现在的位置：买卖IC网 > PDF目录1825 > LT3759EMSE#PBF (Linear Technology)IC REG CTRLR BST INV PWM 12-MSOP PDF资料下载
参数资料
| 型号： | LT3759EMSE#PBF |
| 厂商： | Linear Technology |
| 文件页数： | 10/32页 |
| 文件大小： | 0K |
| 描述： | IC REG CTRLR BST INV PWM 12-MSOP |
| 产品培训模块： | LT3759 DC to DC Controller |
| 标准包装： | 37 |
| PWM 型： | 电流模式 |
| 输出数： | 1 |
| 频率 - 最大： | 1MHz |
| 电源电压： | 1.6 V ~ 42 V |
| 降压： | 无 |
| 升压： | 是 |
| 回扫： | 无 |
| 反相： | 是 |
| 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： | 12-TSSOP （0.118"，3.00mm 宽）裸露焊盘 |
| 包装： | 管件 |
第1页第2页第3页第4页第5页第6页第7页第8页第9页当前第10页第11页第12页第13页第14页第15页第16页第17页第18页第19页第20页第21页第22页第23页第24页第25页第26页第27页第28页第29页第30页第31页第32页
LT3759
APPLICATIONS INFORMATION
LDO STATUS
regulates the INTV CC to 3.75V. V IN LDO is turned off when
the INTV CC voltage is greater than 3.75V (typical). Both
LDO’s can be turned off if the INTV CC pin is driven by a
supply of 4.75V or higher but less than 8V (the INTV CC
maximum voltage rating is 8V). A table of the LDO sup-
ply and output voltage combination is shown in Table 1.
Table 1. LDO’s Supply and Output Voltage Combination (Assuming
That the LDO Dropout Voltage is 0.15V)
SUPPLY VOLTAGES LDO OUTPUT
V IN DRIVE INTV CC (Note 7)
V IN ≤ 3.9V V DRIVE < V IN V IN – 0.15V #1 Is ON
V DRIVE = V IN V IN – 0.15V #1 #2 are ON
V IN < V DRIVE < 4.9V V DRIVE – 0.15V #2 Is ON
cern when a large power MOSFET is being driven at a
high frequency and the V IN voltage is high. It is important
to limit the power dissipation with proper selection of a
MOSFET and/or an operating frequency so the LT3759
does not exceed its maximum junction temperature rating.
The junction temperature T J can be estimated using the
following equations:
T J = T A + P IC ? θ JA
T A = ambient temperature
θ JA = junction-to-ambient thermal resistance
P IC = IC power consumption = V IN ? (I Q + I DRIVE )
3.9V < V IN ≤ 42V
4.9V ≤ V DRIVE ≤ 42V
V DRIVE < 3.9V
V DRIVE = 3.9V
4.75V
3.75V
3.75V
#2 Is ON
#1 Is ON
#1 #2 are ON
(Assume the DRIVE pin is connected to V IN Supply)
I Q = V IN operation I Q = 1.8mA
3.9V < V DRIVE < 4.9V V DRIVE – 0.15V
4.9V ≤ V DRIVE ≤ 42V 4.75V
#2 Is ON
#2 Is ON
I DRIVE = average gate drive current = f ? Q G
f = switching frequency
Note 7: #1 is V IN LDO and #2 is DRIVE LDO
The DRIVE pin provides flexibility to power the gate driver
and the internal loads from a supply that is available only
when the switcher is enabled and running. If not used, the
DRIVE pin should be tied to V IN .
The INTV CC pin must be bypassed to ground immediately
adjacent to the INTV CC pin with a minimum of 4.7μF ceramic
capacitor. Good bypassing is necessary to supply the high
transient currents required by the MOSFET gate driver.
If a low input voltage operation is expected (V IN is 3V or
less), low threshold MOSFETs should be used. The LT3759
contains an undervoltage lockout comparator A8 for the
internal INTV CC supply. The INTV CC undervoltage (UV)
threshold is 1.3V (typical), with 100mV hysteresis, to
ensure that the MOSFETs have sufficient gate drive voltage
before turning on. The logic circuitry within the LT3759
is also powered from the internal INTV CC supply. When
INTV CC is below the UV threshold, the GATE pin will be
forced to GND and the soft-start operation will be triggered.
In an actual application, most of the IC supply current is
used to drive the gate capacitance of the power MOSFET.
The on-chip power dissipation can be a significant con-
Q G = power MOSFET total gate charge
The LT3759 uses packages with an exposed pad for en-
hanced thermal conduction. With proper soldering to the
exposed pad on the underside of the package and a full
copper plane underneath the device, thermal resistance
( θ JA ) will be about 40°C/W for the MSE package.
The LT3759 has an internal INTV CC I DRIVE current limit
function to protect the IC from excessive on-chip power
dissipation. If I DRIVE reaches the current limit, INTV CC
voltage will fall and may trigger the soft-start.
There is a trade-off between the operating frequency and
the size of the power MOSFET (Q G ) in order to maintain
a reliable IC junction temperature. Prior to lowering the
operating frequency, however, be sure to check with
power MOSFET manufacturers for their most recent low
Q G , low R DS(ON) devices. Power MOSFET manufacturing
technologies are continually improving, with newer and
better performance devices being introduced almost yearly.
Operating Frequency and Synchronization
The choice of operating frequency may be determined
by on-chip power dissipation, otherwise it is a trade-off
between efficiency and component size. Low frequency
3759fc
10
For more information www.linear.com/3759
相关PDF资料 |
PDF描述 |
|---|---|
| LT3781IG#TRPBF | IC REG CTRLR ISO PWM CM 20-SSOP |
| LT3782EUFD#PBF | IC REG CTRLR BST PWM CM 28-QFN |
| LT3800IFE#PBF | IC REG CTRLR INV PWM CM 16-TSSOP |
| LT3804EFE#PBF | IC REG CTRLR ISO PWM 28-TSSOP |
| LT3825EFE#PBF | IC REG CTRLR FLYBK ISO 16-TSSOP |
相关代理商/技术参数 |
参数描述 |
|---|---|
| LT3759HMSE#PBF | 功能描述:IC REG CTRLR BST INV PWM 12-MSOP 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:2,500 系列:- PWM 型:电流模式 输出数:1 频率 - 最大:500kHz 占空比:96% 电源电压:4 V ~ 36 V 降压:无 升压:是 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:24-WQFN 裸露焊盘 包装:带卷 (TR) |
| LT3759HMSE#TRPBF | 功能描述:IC REG CTRLR BST INV PWM 12-MSOP 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:2,500 系列:- PWM 型:电流模式 输出数:1 频率 - 最大:500kHz 占空比:96% 电源电压:4 V ~ 36 V 降压:无 升压:是 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:24-WQFN 裸露焊盘 包装:带卷 (TR) |
| LT3759IMSE#PBF | 功能描述:IC REG CTRLR BST INV PWM 12-MSOP 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:2,500 系列:- PWM 型:电流模式 输出数:1 频率 - 最大:500kHz 占空比:96% 电源电压:4 V ~ 36 V 降压:无 升压:是 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:24-WQFN 裸露焊盘 包装:带卷 (TR) |
| LT3759IMSE#TRPBF | 功能描述:IC REG CTRLR BST INV PWM 12-MSOP 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:2,500 系列:- PWM 型:电流模式 输出数:1 频率 - 最大:500kHz 占空比:96% 电源电压:4 V ~ 36 V 降压:无 升压:是 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:24-WQFN 裸露焊盘 包装:带卷 (TR) |
| LT375B | 制造商:EDSYN 功能描述:TIP SPADE 1.5X12.2MM |
发布紧急采购，3分钟左右您将得到回复。