- 您现在的位置：买卖IC网 > PDF目录44988 > LTC1628IG#PBF (LINEAR TECHNOLOGY CORP) 3 A SWITCHING CONTROLLER, 310 kHz SWITCHING FREQ-MAX, PDSO28 PDF资料下载
参数资料
| 型号： | LTC1628IG#PBF |
| 厂商： | LINEAR TECHNOLOGY CORP |
| 元件分类： | 稳压器 |
| 英文描述： | 3 A SWITCHING CONTROLLER, 310 kHz SWITCHING FREQ-MAX, PDSO28 |
| 封装： | 0.209 INCH, PLASTIC, SSOP-28 |
| 文件页数： | 9/32页 |
| 文件大小： | 360K |
| 代理商： | LTC1628IG#PBF |
第1页第2页第3页第4页第5页第6页第7页第8页当前第9页第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
17
LTC1628/LTC1628-PG
Manufacturers such as Nichicon, United Chemicon and
Sanyo can be considered for high performance through-
hole capacitors. The OS-CON semiconductor dielectric
capacitor available from Sanyo has the lowest (ESR)(size)
product of any aluminum electrolytic at a somewhat
higher price. An additional ceramic capacitor in parallel
with OS-CON capacitors is recommended to reduce the
inductance effects.
In surface mount applications multiple capacitors may
need to be used in parallel to meet the ESR, RMS current
handling and load step requirements of the application.
Aluminum electrolytic, dry tantalum and special polymer
capacitors are available in surface mount packages. Spe-
cial polymer surface mount capacitors offer very low ESR
but have lower storage capacity per unit volume than other
capacitor types. These capacitors offer a very cost-effec-
tive output capacitor solution and are an ideal choice when
combined with a controller having high loop bandwidth.
Tantalum capacitors offer the highest capacitance density
and are often used as output capacitors for switching
regulators having controlled soft-start. Several excellent
surge-tested choices are the AVX TPS, AVX TPSV or the
KEMET T510 series of surface mount tantalums, available
in case heights ranging from 2mm to 4mm. Aluminum
electrolytic capacitors can be used in cost-driven applica-
tions providing that consideration is given to ripple current
ratings, temperature and long term reliability. A typical
application will require several to many aluminum electro-
lytic capacitors in parallel. A combination of the above
mentioned capacitors will often result in maximizing per-
formance and minimizing overall cost. Other capacitor
types include Nichicon PL series, NEC Neocap, Pansonic
SP and Sprague 595D series. Consult manufacturers for
other specific recommendations.
INTVCC Regulator
An internal P-channel low dropout regulator produces 5V
at the INTVCC pin from the VIN supply pin. INTVCC powers
the drivers and internal circuitry within the LTC1628. The
INTVCC pin regulator can supply a peak current of 50mA
and must be bypassed to ground with a minimum of
4.7
F tantalum, 10F special polymer, or low ESR type
electrolytic capacitor. A 1
F ceramic capacitor placed
directly adjacent to the INTVCC and PGND IC pins is highly
recommended. Good bypassing is necessary to supply
the high transient currents required by the MOSFET gate
drivers and to prevent interaction between channels.
Higher input voltage applications in which large MOSFETs
are being driven at high frequencies may cause the maxi-
mum junction temperature rating for the LTC1628 to be
exceeded. The system supply current is normally domi-
nated by the gate charge current. Additional external
loading of the INTVCC and 3.3V linear regulators also
needs to be taken into account for the power dissipation
calculations. The total INTVCC current can be supplied by
either the 5V internal linear regulator or by the EXTVCC
input pin. When the voltage applied to the EXTVCC pin is
less than 4.7V, all of the INTVCC current is supplied by the
internal 5V linear regulator. Power dissipation for the IC in
this case is highest: (VIN)(IINTVCC), and overall efficiency
is lowered. The gate charge current is dependent on
operating frequency as discussed in the Efficiency Consid-
erations section. The junction temperature can be esti-
mated by using the equations given in Note 2 of the
Electrical Characteristics. For example, the LTC1628 VIN
current is limited to less than 24mA from a 24V supply
when not using the EXTVCC pin as follows:
TJ = 70°C + (24mA)(24V)(95°C/W) = 125°C
Use of the EXTVCC input pin reduces the junction tempera-
ture to:
TJ = 70°C + (24mA)(5V)(95°C/W) = 81°C
Dissipation should be calculated to also include any added
current drawn from the internal 3.3V linear regulator. To
prevent maximum junction temperature from being ex-
ceeded, the input supply current must be checked operat-
ing in continuous mode at maximum VIN.
EXTVCC Connection
The LTC1628 contains an internal P-channel MOSFET
switch connected between the EXTVCC and INTVCC pins.
When the voltage applied to EXTVCC rises above 4.7V, the
internal regulator is turned off and the switch closes,
connecting the EXTVCC pin to the INTVCC pin thereby
supplying internal power. The switch remains closed as
long as the voltage applied to EXTVCC remains above 4.5V.
This allows the MOSFET driver and control power to be
APPLICATIO S I FOR ATIO
WU
UU
相关PDF资料 |
PDF描述 |
|---|---|
| LTC1628IG-SYNC#TR | 3 A SWITCHING CONTROLLER, 360 kHz SWITCHING FREQ-MAX, PDSO28 |
| LTC1643HCGN#PBF | 4-CHANNEL POWER SUPPLY SUPPORT CKT, PDSO16 |
| LTC1643LCGN#TR | 4-CHANNEL POWER SUPPLY SUPPORT CKT, PDSO16 |
| LTC1728HS5-5 | 3-CHANNEL POWER SUPPLY SUPPORT CKT, PDSO5 |
| LTC1729CS8-8.4#TR | 1-CHANNEL POWER SUPPLY SUPPORT CKT, PDSO8 |
相关代理商/技术参数 |
参数描述 |
|---|---|
| LTC1628IG-PG | 功能描述:IC REG CTRLR BUCK PWM CM 28-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 |
| LTC1628IG-PG#PBF | 功能描述:IC REG CTRLR BUCK PWM CM 28-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 |
| LTC1628IG-PG#TR | 功能描述:IC REG CTRLR BUCK PWM CM 28-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 |
| LTC1628IG-PG#TRPBF | 功能描述:IC REG CTRLR BUCK PWM CM 28-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 |
| LTC1628IGSYNC | 制造商:Linear Technology 功能描述: |
发布紧急采购，3分钟左右您将得到回复。