- 您现在的位置：买卖IC网 > PDF目录15313 > LT3800EFE#TRPBF (Linear Technology)IC REG CTRLR INV PWM CM 16-TSSOP PDF资料下载
参数资料
| 型号： | LT3800EFE#TRPBF |
| 厂商： | Linear Technology |
| 文件页数： | 18/24页 |
| 文件大小： | 0K |
| 描述： | IC REG CTRLR INV PWM CM 16-TSSOP |
| 标准包装： | 2,500 |
| PWM 型： | 电流模式 |
| 输出数： | 1 |
| 频率 - 最大： | 220kHz |
| 占空比： | 95% |
| 电源电压： | 4 V ~ 60 V |
| 降压： | 是 |
| 升压： | 无 |
| 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： | 16-TSSOP（0.173"，4.40mm）裸露焊盘 |
| 包装： | 带卷 (TR) |
LT3800
APPLICATIONS INFORMATION
current. Commutating this diode requires a signi?cant
charge contribution from the main switch. At the instant
the body diode commutates, a current discontinuity is
created and parasitic inductance causes the switch node
to ?y up in response to this discontinuity. High cur-
rents and excessive parasitic inductance can generate
extremely fast dV/dt rise times. This phenomenon can
cause avalanche breakdown in the synchronous FET
body diode, signi?cant inductive overshoot on the switch
node, and shoot-through currents via parasitic turn-on of
the synchronous FET. Layout practices and component
orientations that minimize parasitic inductance on this
node is critical for reducing these effects.
Ringing waveforms in a converter circuit can lead to device
failure, excessive EMI, or instability. In many cases, you
can damp a ringing waveform with a series RC network
across the offending device. In LT3800 applications, any
ringing will typically occur on the switch node, which
can usually be reduced by placing a snubber across the
synchronous FET. Use of a snubber network, however,
should be considered a last resort. Effective layout practices
typically reduce ringing and overshoot, and will eliminate
the need for such solutions.
Effective grounding techniques are critical for successful
DC/DC converter layouts. Orient power path components
such that current paths in the ground plane do not cross
through signal ground areas. Signal ground refers to the
Exposed Pad on the backside of the LT3800 IC. SGND
is referenced to the (–) terminal of the V OUT decoupling
capacitor and is used as the converter voltage feedback
reference. Power ground currents are controlled on the
LT3800 via the PGND pin, and this ground references
the high current synchronous switch drive components,
as well as the local V CC supply. It is important to keep
PGND and SGND voltages consistent with each other, so
separating these grounds with thin traces is not recom-
mended. When the synchronous FET is turned on, gate
drive surge currents return to the LT3800 PGND pin from
the FET source. The BOOST supply refresh surge currents
also return through this same path. The synchronous FET
must be oriented such that these PGND return currents do
not corrupt the SGND reference. Problems caused by the
PGND return path are generally recognized during heavy
load conditions, and are typically evidenced as multiple
switch pulses occurring during a single 5μs switch cycle.
This behavior indicates that SGND is being corrupted and
grounding should be improved. SGND corruption can
often be eliminated, however, by adding a small capacitor
(100pF-200pF) across the synchronous switch FET from
drain to source.
The high di/dt loop formed by the switch MOSFETs and
the input capacitor (C IN ) should have short wide traces
to minimize high frequency noise and voltage stress from
inductive ringing. Surface mount components are preferred
to reduce parasitic inductances from component leads.
Connect the drain of the main switch MOSFET directly to
the (+) plate of C IN , and connect the source of the syn-
chronous switch MOSFET directly to the (–) terminal of
C IN . This capacitor provides the AC current to the switch
MOSFETs. Switch path currents can be controlled by
orienting switch FETs, the switched inductor, and input
and output decoupling capacitors in close proximity to
each other.
Locate the V CC and BOOST decoupling capacitors in close
proximity to the IC. These capacitors carry the MOSFET
drivers’ high peak currents. Locate the small-signal
components away from high frequency switching nodes
(BOOST, SW, TG, V CC and BG). Small-signal nodes are
oriented on the left side of the LT3800, while high current
switching nodes are oriented on the right side of the IC
to simplify layout. This also helps prevent corruption of
the SGND reference.
Connect the V FB pin directly to the feedback resistors
independent of any other nodes, such as the SENSE – pin.
The feedback resistors should be connected between the
(+) and (–) terminals of the output capacitor (C OUT ).
Locate the feedback resistors in close proximity to the
LT3800 to minimize the length of the high impedance
V FB node.
The SENSE – and SENSE + traces should be routed together
and kept as short as possible.
3800fc
18
相关PDF资料 |
PDF描述 |
|---|---|
| VI-2WD-EW-F1 | CONVERTER MOD DC/DC 85V 100W |
| UVK1A472MHD | CAP ALUM 4700UF 10V 20% RADIAL |
| VI-2WB-EY-B1 | CONVERTER MOD DC/DC 95V 50W |
| PCF1E470MCL1GS | CAP ALUM 47UF 25V 20% SMD |
| ECA43DCBI | CONN EDGECARD 86POS R/A .125 SLD |
相关代理商/技术参数 |
参数描述 |
|---|---|
| LT3800IFE | 制造商:Linear Technology 功能描述:Conv DC-DC Single Step Down 4V to 60V 16-Pin TSSOP EP |
| LT3800IFE#PBF | 功能描述:IC REG CTRLR INV PWM CM 16-TSSOP 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 |
| LT3800IFE#PBF | 制造商:Linear Technology 功能描述:IC SYNC STEP-DOWN REGULATOR CTRL 16-TSSO |
| LT3800IFE#TR | 制造商:Linear Technology 功能描述:Conv DC-DC Single Step Down 4V to 60V 16-Pin TSSOP EP T/R |
| LT3800IFE#TRPBF | 功能描述:IC REG CTRLR INV PWM CM 16-TSSOP 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 |
发布紧急采购，3分钟左右您将得到回复。