- 您现在的位置：买卖IC网 > PDF目录17351 > LM2595ATPBCKGEVB (ON Semiconductor)EVAL BOARD FOR LM2595ATPBCKG PDF资料下载
参数资料
| 型号： | LM2595ATPBCKGEVB |
| 厂商： | ON Semiconductor |
| 文件页数： | 18/25页 |
| 文件大小： | 0K |
| 描述： | EVAL BOARD FOR LM2595ATPBCKG |
| 设计资源： | LM2595ATPBCKGEVB BOM LM2595ATPBCKGEVB Gerber Files LM2595ATPBCKGEVB Schematic |
| 特色产品： | Evaluation Boards & Kits |
| 标准包装： | 1 |
| 主要目的： | DC/DC，步降 |
| 输出及类型： | 1，非隔离 |
| 输出电压： | 5V |
| 电流 - 输出： | 1A |
| 输入电压： | 4.5 ~ 40 V |
| 稳压器拓扑结构： | 降压 |
| 频率 - 开关： | 150kHz |
| 板类型： | 完全填充 |
| 已供物品： | 板 |
| 已用 IC / 零件： | LM2595 |
| 其它名称： | LM2595ATPBCKGEVBOS |
LM2595
x t on
[ Load
in
O
in
peak
2L 1
V
O
x 1.0 , and f osc + 52 kHz.
f osc
where t on +
in
O
ADDITIONAL APPLICATIONS
Inverting Regulator
An inverting buck ? boost regulator using the LM2595 is
shown in Figure 23. This circuit converts a positive input
voltage to a negative output voltage with a common ground
by bootstrapping the regulators ground to the negative
output voltage. By grounding the feedback pin, the regulator
senses the inverted output voltage and regulates it.
In this example the LM2595 is used to generate a ? 12 V
output. The maximum input voltage in this case cannot
exceed +28 V because the maximum voltage appearing
across the regulator is the absolute sum of the input and
output voltages and this must be limited to a maximum of
40 V.
This circuit configuration is able to deliver approximately
0.25 A to the output when the input voltage is 12 V or higher.
At lighter loads the minimum input voltage required drops
to approximately 4.7 V, because the buck ? boost regulator
topology can produce an output voltage that, in its absolute
value, is either greater or less than the input voltage.
Since the switch currents in this buck ? boost configuration
are higher than in the standard buck converter topology, the
available output current is lower.
This type of buck ? boost inverting regulator can also
require a larger amount of startup input current, even for
light loads. This may overload an input power source with
a current limit less than 1.0 A.
Such an amount of input startup current is needed for at
least 2.0 ms or more. The actual time depends on the output
voltage and size of the output capacitor.
Because of the relatively high startup currents required by
this inverting regulator topology, the use of a delayed startup
or an undervoltage lockout circuit is recommended.
Using a delayed startup arrangement, the input capacitor
can charge up to a higher voltage before the switch ? mode
regulator begins to operate.
The high input current needed for startup is now partially
supplied by the input capacitor C in .
It has been already mentioned above, that in some
situations, the delayed startup or the undervoltage lockout
features could be very useful. A delayed startup circuit
applied to a buck ? boost converter is shown in Figure 28.
Figure 30 in the “Undervoltage Lockout” section describes
an undervoltage lockout feature for the same converter
topology.
Design Recommendations:
The inverting regulator operates in a different manner
than the buck converter and so a different design procedure
has to be used to select the inductor L1 or the output
capacitor C out .
The output capacitor values must be larger than what is
normally required for buck converter designs. Low input
voltages or high output currents require a large value output
capacitor (in the range of thousands of m F).
The recommended range of inductor values for the
inverting converter design is between 68 m H and 220 m H. To
select an inductor with an appropriate current rating, the
inductor peak current has to be calculated.
The following formula is used to obtain the peak inductor
current:
I (V ) |V |) V
I )
in
|V |
V ) |V |
Under normal continuous inductor current operating
conditions, the worst case occurs when V in is minimal.
12 to 40 V
Feedback
R4
Unregulated
DC Input
+V in
LM2595
L1
100 m H
C in
100 m F/50 V
C1
0.1 m F
ON/OFF
R2
47k
GND
D1
1N5819
R3
C out
220 m F
C FF
? 12 V @ 0.25 A
Regulated
Output
Figure 24. Inverting Buck ? Boost Develops with Delayed Startup
http://onsemi.com
18
相关PDF资料 |
PDF描述 |
|---|---|
| SJA7502-1-1/2-50-BLACK | HOOK BLACK 1 1/2" X 50YD X 0.12" |
| A9BAA-1308F | FLEX CABLE - AFF13A/AF13/AFE13T |
| RBM06DCWN | CONN EDGECARD 12POS DIP .156 SLD |
| LQW2UAS33NJ00L | IND 33NH 1000MA SRF 1600MHZ 1008 |
| RBM06DCWH | CONN EDGECARD 12POS DIP .156 SLD |
相关代理商/技术参数 |
参数描述 |
|---|---|
| LM2595DSADJG | 功能描述:直流/直流开关调节器 1A BUCK SW REG 150KHZ RoHS:否 制造商:International Rectifier 最大输入电压:21 V 开关频率:1.5 MHz 输出电压:0.5 V to 0.86 V 输出电流:4 A 输出端数量: 最大工作温度: 安装风格:SMD/SMT 封装 / 箱体:PQFN 4 x 5 |
| LM2595DSADJR4G | 功能描述:直流/直流开关调节器 1A BUCK SW REG 150KHZ RoHS:否 制造商:International Rectifier 最大输入电压:21 V 开关频率:1.5 MHz 输出电压:0.5 V to 0.86 V 输出电流:4 A 输出端数量: 最大工作温度: 安装风格:SMD/SMT 封装 / 箱体:PQFN 4 x 5 |
| LM2595S12 | 制造商:Texas Instruments 功能描述:SWITCHING REG, 1A 12V, SMD, 2595 制造商:Texas Instruments 功能描述:SWITCHING REG, 1A 12V, SMD, 2595; Primary Input Voltage:24V; No. of Outputs:1; Output Voltage:12V; Output Current:1A; Voltage Regulator Case Style:TO-263; No. of Pins:5; Operating Temperature Min:-25C; Operating Temperature ;RoHS Compliant: Yes |
| LM2595S-12 | 功能描述:直流/直流开关转换器 RoHS:否 制造商:STMicroelectronics 最大输入电压:4.5 V 开关频率:1.5 MHz 输出电压:4.6 V 输出电流:250 mA 输出端数量:2 最大工作温度:+ 85 C 安装风格:SMD/SMT |
| LM2595S12 | 制造商:Texas Instruments 功能描述:IC SWITCHING REG 1A 12V SMD 2595 |
发布紧急采购，3分钟左右您将得到回复。