- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄358130 > MAX1947ETA24 (MAXIM INTEGRATED PRODUCTS INC) SWITCHING REGULATOR, DSO8 PDF資料下載
參數(shù)資料
| 型號： | MAX1947ETA24 |
| 廠商： | MAXIM INTEGRATED PRODUCTS INC |
| 元件分類： | 穩(wěn)壓器 |
| 英文描述： | SWITCHING REGULATOR, DSO8 |
| 封裝： | 3 X 3 MM, 0.80 MM HEIGHT, MO229/WEEC, EXPOSED PAD, TDFN-8 |
| 文件頁數(shù)： | 7/10頁 |
| 文件大?。?/td> | 817K |
| 代理商： | MAX1947ETA24 |
Control Scheme
The MAX1947 is a bootstrapped design. Upon turn-on,
a startup oscillator brings the output voltage high
enough to allow the main DC-DC circuitry to run. Once
the output voltage reaches 1.62V (typ) the main DC-DC
circuitry turns on and boosts the output voltage to the
final regulation point.
The unique minimum off-time, current-limited control
scheme is the key to the MAX1947’s low operating cur-
rent and high efficiency over a wide load range. The
architecture combines the high output power and effi-
ciency of a pulse-width modulation (PWM) device with
the ultra-low quiescent current of a traditional pulse-
skipping controller. The switching frequency can be as
high as 2MHz and depends upon the load current and
input voltage. The MAX1947 is designed to operate
using low-ESR ceramic capacitors, so output voltage
ripple due to ESR is very small (approximately 10mV
P-P
).
Track Mode
The MAX1947 enters track mode when BATT is greater
than the output-voltage regulation point. Track mode
can only be entered under the following conditions:
V
BATT
> V
OUT
, V
OUT
> V
OUT
regulation point, and the
minimum off-time expires. During track mode, the syn-
chronous rectifier is turned on 100% of the time and the
output voltage tracks the battery voltage. Track mode is
exited by V
OUT
falling below the V
OUT
regulation point.
Synchronous Rectification
The internal synchronous rectifier eliminates the need
for an external Schottky diode, reducing cost and board
space. During the cycle off-time, the p-channel MOSFET
turns on and shunts the MOSFET body diode. As a
result, the synchronous rectifier significantly improves
efficiency without the addition of an external compo-
nent. Conversion efficiency can be as high as 94%.
RESET
The MAX1947 features an active-low push-pull
RESET
output for use with a microcontroller (μC). It signals the
μC when the MAX1947 output voltage is within operat-
ing limits. During startup,
RESET
is held low. When the
RESET
threshold (90% of the output regulation voltage)
is reached, a 75ms (min) timer begins counting.
RESET
is switched high once the timer expires.
M
Low Input/Output Voltage
Step-Up DC-DC Converter with
RESET
_______________________________________________________________________________________
7
Functional Diagram
STARTUP
OSCILLATOR
SHUTDOWN
CIRCUITRY
t
MAX TIMER
CONTROL
LOGIC AND
GATE DRIVERS
BATT
SHDN
0.9 x REF
REF
ERROR
AMPLIFIER
ZERO-CROSSING
AMPLIFIER
CURRENT-LIMIT
AMPLIFIER
P*
N
LX
PGND
OUT
RESET
75ms TIMER
t
OFF
MIN TIMER
1.25V REFERENCE
(REF)
GND
MAX1947
REF
*BODY DIODE CONTROL
相關PDF資料 |
PDF描述 |
|---|---|
| MAX2674EWT+T | TELECOM, CELLULAR, RF AND BASEBAND CIRCUIT, PBGA6 |
| MAX6310EUK34D3+T | 1-CHANNEL POWER SUPPLY SUPPORT CKT, PDSO5 |
| MB1-120-01-S-01-SL | 20 CONTACT(S), FEMALE, RIGHT ANGLE SINGLE PART CARD EDGE CONN, SURFACE MOUNT |
| MB1-120-01-S-02-SL | 20 CONTACT(S), FEMALE, RIGHT ANGLE SINGLE PART CARD EDGE CONN, SURFACE MOUNT |
| MB1-130-01-S-01-SL | 30 CONTACT(S), FEMALE, RIGHT ANGLE SINGLE PART CARD EDGE CONN, SURFACE MOUNT |
相關代理商/技術參數(shù) |
參數(shù)描述 |
|---|---|
| MAX1947ETA25 | 制造商:Rochester Electronics LLC 功能描述: 制造商:Maxim Integrated Products 功能描述: |
| MAX1947ETA25+ | 制造商:Maxim Integrated Products 功能描述:CONV DC-DC SGL-OUT STEP UP 8TDFN EP - Rail/Tube |
| MAX1947ETA25+T | 功能描述:直流/直流開關轉換器 Step-Up w/RESET DC/DC Converter RoHS:否 制造商:STMicroelectronics 最大輸入電壓:4.5 V 開關頻率:1.5 MHz 輸出電壓:4.6 V 輸出電流:250 mA 輸出端數(shù)量:2 最大工作溫度:+ 85 C 安裝風格:SMD/SMT |
| MAX1947ETA25-T | 功能描述:直流/直流開關轉換器 RoHS:否 制造商:STMicroelectronics 最大輸入電壓:4.5 V 開關頻率:1.5 MHz 輸出電壓:4.6 V 輸出電流:250 mA 輸出端數(shù)量:2 最大工作溫度:+ 85 C 安裝風格:SMD/SMT |
| MAX1947ETA30+ | 制造商:Maxim Integrated Products 功能描述:CONV DC-DC SGL-OUT STEP UP 8TDFN EP - Rail/Tube 制造商:Maxim Integrated Products 功能描述:STEP-UP DC-DC CONVERTER WITH ACTIVE-LOW |
發(fā)布緊急采購，3分鐘左右您將得到回復。