- 您现在的位置：买卖IC网 > PDF目录97720 > TC125501ECTRT 0.4 A SWITCHING REGULATOR, 115 kHz SWITCHING FREQ-MAX, PDSO5 PDF资料下载
参数资料
| 型号： | TC125501ECTRT |
| 元件分类： | 稳压器 |
| 英文描述： | 0.4 A SWITCHING REGULATOR, 115 kHz SWITCHING FREQ-MAX, PDSO5 |
| 封装： | EIAJ, SC-74A, SOT-23A, 5 PIN |
| 文件页数： | 6/10页 |
| 文件大小： | 84K |
| 代理商： | TC125501ECTRT |
5
TC125
TC126
PFM Step-Up DC/DC Regulators
TC125/6-1 8/3/99
2001 Microchip Technology Inc
DS21372A
Figure 3. TC125/6 Demo Board Parts
the internal N-channel switch is ON, the oscillator frequency
automatically doubles to minimize ON time. Although re-
duced, switch current still flows because the regulator re-
mains in operation. Therefore, the LX input is not internally
current limited and care must be taken never to exceed the
350 mA maximum limit. Failure to observe this will result in
damage to the regulator.
Output Diode
For best results, use a Schottky diode such as the
MA735, 1N5817, MBR0520L, or equivalent. Connect the
diode between the PS and LX pins (TC125) or SENSE and
LX pins (TC126) as close to the IC as possible. (Do not use
ordinary rectifier diodes since the higher threshold voltages
reduce efficiency.)
Output Capacitor
The effective series resistance of the output capacitor
directly affects the amplitude of the output voltage ripple.
(The product of the peak inductor current and the ESR
determines output ripple amplitude.) Therefore, a capacitor
with the lowest possible ESR should be selected. Smaller
capacitors are acceptable for light loads or in applications
where ripple is not a concern. The Sprague 595D series of
tantalum capacitors are among the smallest of all low ESR
surface mount capacitors available. Table 1 lists suggested
component numbers and manufacturers.
Board Layout Guidelines
As with all inductive switching regulators, the TC125/6
generate fast switching waveforms that radiate noise. Inter-
connecting lead lengths should be minimized to keep stray
capacitance, trace resistance, and radiated noise as low as
possible. In addition, the GND pin, input bypass capacitor,
and output filter capacitor ground leads should be con-
nected to a single point. The input capacitor should be
placed as close to power and ground pins of the TC125/6 as
possible.
TC125/6 DEMO Card
The TC125/6 DEMO Card can be used to evaluate this
series of products. It is a pre-etched and drilled PC card with
jumper options to accomodate either device (Figure 3).
These cards are available from your local TelCom Semicon-
ductor sales office.
Using the TC125/6 DEMO Board
Mount the TC125/6 on the foil side of the circuit board
(Figure 3). The diode, input and output capacitors, and
inductor are mounted on the blank side of the board in the
locations specified. Jumper locations J1, J2, J3 can be
soldered in place as in Table 2, or shorting strips can be
installed to facilitate easy reconfiguration. If shorting strips
are used, specify 0.1”, single row strip, such as DigiKey
S1012 - 36 - ND.
Table 2.
Device
J1
J2
J3
TC125
Short SD to ON
Short VDD to VOUT
Leave
OPEN
TC126
Leave OPEN
Short VDD to VOUT
Short
SENSE
to VOUT
Note that there are two sets of inductor mounting holes
to accomodate various sizes of through-hole inductors.
Once the components are installed, configure the shorting
blocks for normal operation as follows:
The TC125 is placed in shutdown by removing the
shorting block (J1) BETWEEN SD and ON and installing it
between SD and OFF (J1). The TC126 uses external VDD
input when the shorting block between VDD and VOUT is
removed from J2 and installed between VDD and EXT. The
EXT VDD pad on the board is then wired to desired 2.2V to
10V source. Likewise, external feedback sensing is selected
by removing the shorting block between SENSE and VOUT
and installing it between VOUT and EXT. The EXT SENSE
pad on the board is then wired to the desired location.
Important: Never install shorting blocks on J1 SD to
OFF and F3 SENSE to VOUT at the same time. This
combination of shorting blocks shorts the input supply!
C
OUT
D1
VIN
VOUT
C
IN
J1
EXT
SENSE
EXT VDD VOUT
J2
L1
J2
V
DD
EXT
V
OUT
EXT
SENSE
V
OUT
V
DD
Select
SENSE
Select
ON SD OFF
Shutdown
Control
J3
J1
TC125/6
(Mount on Reverse Side of Board)
SD
V
OUT SENSE EXT
J3
ON
OFF
EXT
V
DD
相关PDF资料 |
PDF描述 |
|---|---|
| TC1684EUA | SWITCHED CAPACITOR CONVERTER, 170 kHz SWITCHING FREQ-MAX, PDSO8 |
| TC3402VQRRT/723 | 4-CH 16-BIT DELTA-SIGMA ADC, SERIAL ACCESS, PDSO16 |
| TC3402VQRRT/723 | 4-CH 16-BIT DELTA-SIGMA ADC, SERIAL ACCESS, PDSO16 |
| TC3402VQRTR/713 | 4-CH 16-BIT DELTA-SIGMA ADC, SERIAL ACCESS, PDSO16 |
| TC3402VQRTR/713 | 4-CH 16-BIT DELTA-SIGMA ADC, SERIAL ACCESS, PDSO16 |
相关代理商/技术参数 |
参数描述 |
|---|---|
| TC125501ECTTR | 功能描述:开关变换器、稳压器与控制器 PFM Step-up DC/DC RoHS:否 制造商:Texas Instruments 输出电压:1.2 V to 10 V 输出电流:300 mA 输出功率: 输入电压:3 V to 17 V 开关频率:1 MHz 工作温度范围: 安装风格:SMD/SMT 封装 / 箱体:WSON-8 封装:Reel |
| TC125A | 制造商:Thomas & Betts 功能描述:Fittings Connector 1.5inch Steel |
| TC125SC-1 | 制造商:Thomas & Betts 功能描述:1-1/2 EMT SET SCREW CONN,EA |
| TC125-TB | 制造商:Thomas & Betts 功能描述:CABLE TIES |
| TC126 | 制造商:MICROCHIP 制造商全称:Microchip Technology 功能描述:PFM Step-Up DC/DC Regulators |
发布紧急采购，3分钟左右您将得到回复。