- 您现在的位置：买卖IC网 > PDF目录79959 > LM2575-33IN (TEXAS INSTRUMENTS INC) 4 A SWITCHING REGULATOR, 63 kHz SWITCHING FREQ-MAX, PDIP16 PDF资料下载
参数资料
| 型号： | LM2575-33IN |
| 厂商： | TEXAS INSTRUMENTS INC |
| 元件分类： | 稳压器 |
| 英文描述： | 4 A SWITCHING REGULATOR, 63 kHz SWITCHING FREQ-MAX, PDIP16 |
| 封装： | MS-001BB, PLASTIC, DIP-16 |
| 文件页数： | 11/12页 |
| 文件大小： | 195K |
| 代理商： | LM2575-33IN |
www.ti.com
Input Capacitor (C
IN)
I
C,RMS
u 1.2(
ton
T
) I
LOAD, where:
ton
T
+
V
OUT
V
IN
{buck regulator}, and
ton
T
+
|V
OUT|
(|V
OUT| ) VIN)
{buckboost regulator}
Output Capacitor (C
OUT)
Catch Diode
Inductor
LM2575
1-A SIMPLE STEP-DOWN SWITCHING VOLTAGE REGULATOR
SLVS569D – JANUARY 2005 – REVISED JULY 2005
APPLICATION INFORMATION (continued)
For stability concerns, an input bypass capacitor (electrolytic, CIN ≥ 47 F) needs to be located as close as
possible to the regulator. For operating temperatures below –25
°C, C
IN may need to be larger in value. In
addition, since most electrolytic capacitors have decreasing capacitances and increasing ESR as temperature
drops, adding a ceramic or solid tantalum capacitor in parallel increases the stability in cold temperatures.
To extend the capacitor operating lifetime, the capacitor RMS ripple current rating should be:
For both loop stability and filtering of ripple voltage, an output capacitor also is required, again in close proximity
to the regulator. For best performance, low-ESR aluminum electrolytics are recommended, although standard
aluminum electrolytics may be adequate for some applications. Based on the following equation:
Output Ripple Voltage = (ESR of COUT) × (inductor ripple current)
Output ripple of 50 mV to 150 mV typically can be achieved with capacitor values of 220
F to 680 F. Larger
COUT can reduce the ripple 20 mV to 50 mV peak-to-peak. To improve further on output ripple, paralleling of
standard electrolytic capacitors may be used. Alternatively, higher-grade capacitors such as “high frequency”,
“low inductance”, or “low ESR” can be used.
The following should be taken into account when selecting COUT:
At cold temperatures, the ESR of the electrolytic capacitors can rise dramatically (typically 3
× nominal value
at –25
°C). Because solid tantalum capacitors have significantly better ESR specifications at cold
temperatures, they should be used at operating temperature lower than –25
°C. As an alternative, tantalums
also can be paralleled to aluminum electrolytics and should contribute 10% to 20% to the total capacitance.
Low ESR for COUT is desirable for low output ripple. However, the ESR should be greater than 0.05 to
avoid the possibility of regulator instability. Hence, a sole tantalum capacitor used for COUT is most
susceptible to this occurrence.
The capacitor’s ripple current rating of 52 kHz should be at least 50% higher than the peak-to-peak inductor
ripple current.
As with other external components, the catch diode should be placed close to the output to minimize unwanted
noise. Schottky diodes have fast switching speeds and low forward voltage drops and, thus, offer the best
performance, especially for switching regulators with low output voltages (VOUT < 5 V). If a high-efficiency,
fast-recovery, or ultra-fast-recovery diode is used in place of a Schottky, it should have a soft recovery (versus
abrupt turn-off characteristics) to avoid the chance of causing instability and EMI. Standard 50-/60-Hz diodes,
such as the 1N4001 or 1N5400 series, are NOT suitable.
Proper inductor selection is key to the performance-switching power-supply designs. One important factor to
consider is whether the regulator will be used in continuous (inductor current flows continuously and never drops
to zero) or in discontinuous mode (inductor current goes to zero during the normal switching cycle). Each mode
has distinctively different operating characteristics and, therefore, can affect the regulator performance and
requirements. In many applications, the continuous mode is the preferred mode of operation, since it offers
greater output power with lower peak currents, and also can result in lower output ripple voltage. The advantages
of continuous mode of operation come at the expense of a larger inductor required to keep inductor current
continuous, especially at low output currents and/or high input voltages.
8
相关PDF资料 |
PDF描述 |
|---|---|
| LM2575IKTT | 4 A SWITCHING REGULATOR, 63 kHz SWITCHING FREQ-MAX, PSSO5 |
| LM4040B41ILPM | 1-OUTPUT TWO TERM VOLTAGE REFERENCE, 4.096 V, PBCY3 |
| L9942XP | STEPPER MOTOR CONTROLLER, 2.5 A, PDSO24 |
| LS4001-9PD3TB1 | 1-OUTPUT 100 W AC-DC PWR FACTOR CORR MODULE |
| LS5660-9PD0T | 2-OUTPUT 100 W AC-DC PWR FACTOR CORR MODULE |
相关代理商/技术参数 |
参数描述 |
|---|---|
| LM2575-5 | 制造商:MOTOROLA 制造商全称:Motorola, Inc 功能描述:EASY SWITCHERE⑩ 1.0 A STEP-DOWN VOLTAGE REGULATOR |
| LM2575-5.0BN | 功能描述:IC REG BUCK 5V 1A 16DIP RoHS:否 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 开关稳压器 系列:- 标准包装:20 系列:SIMPLE SWITCHER® 类型:降压（降压） 输出类型:固定 输出数:1 输出电压:12V 输入电压:4 V ~ 60 V PWM 型:电压模式 频率 - 开关:52kHz 电流 - 输出:1A 同步整流器:无 工作温度:-40°C ~ 125°C 安装类型:通孔 封装/外壳:16-DIP（0.300"，7.62mm） 包装:管件 供应商设备封装:16-DIP 其它名称:*LM2575HVN-12LM2575HVN-12 |
| LM2575-5.0BT | 功能描述:IC REG BUCK 5V 1A TO220-5 RoHS:否 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 开关稳压器 系列:- 标准包装:20 系列:SIMPLE SWITCHER® 类型:降压（降压） 输出类型:固定 输出数:1 输出电压:12V 输入电压:4 V ~ 60 V PWM 型:电压模式 频率 - 开关:52kHz 电流 - 输出:1A 同步整流器:无 工作温度:-40°C ~ 125°C 安装类型:通孔 封装/外壳:16-DIP（0.300"，7.62mm） 包装:管件 供应商设备封装:16-DIP 其它名称:*LM2575HVN-12LM2575HVN-12 |
| LM2575-5.0BT L3 | 制造商:Micrel 功能描述:The Micrel LM2575-5.0BT L3 is a 5V Buck Regulator. |
| LM2575-5.0BU | 功能描述:IC REG BUCK 5V 1A TO263-5 RoHS:否 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 开关稳压器 系列:- 标准包装:20 系列:SIMPLE SWITCHER® 类型:降压（降压） 输出类型:固定 输出数:1 输出电压:12V 输入电压:4 V ~ 60 V PWM 型:电压模式 频率 - 开关:52kHz 电流 - 输出:1A 同步整流器:无 工作温度:-40°C ~ 125°C 安装类型:通孔 封装/外壳:16-DIP（0.300"，7.62mm） 包装:管件 供应商设备封装:16-DIP 其它名称:*LM2575HVN-12LM2575HVN-12 |
发布紧急采购，3分钟左右您将得到回复。