- 您現在的位置：買賣IC網 > PDF目錄371907 > HWD20012EUB (Electronic Theatre Controls, Inc.) High-Efficiency, Low-Supply-Current, Compact, Step-Up DC-DC Converters PDF資料下載
參數資料
| 型號： | HWD20012EUB |
| 廠商： | Electronic Theatre Controls, Inc. |
| 元件分類： | DC/DC變換器 |
| 英文描述： | High-Efficiency, Low-Supply-Current, Compact, Step-Up DC-DC Converters |
| 中文描述： | 高效率，低電源電流，結構緊湊，升壓型DC - DC轉換器 |
| 文件頁數： | 7/13頁 |
| 文件大小： | 787K |
| 代理商： | HWD20012EUB |
Detailed Desc ription
The
HWD20011/HWD2001/HWD20012
compact, step-up
DC-DC converters start up with voltages as low as 0.9V
and operate with an input voltage down to 0.7V.
Consuming only 16μA of quiescent current, these
devices offer a built-in synchronous rectifier that
reduces cost by eliminating the need for an external
diode and improves overall efficiency by minimizing
losses in the circuit (see
Synchronous Rectification
sec-
tion for details). The internal MOSFET resistance is typi-
cally 0.3
, which minimizes losses. The current limit of
the
HWD20011
and
HWD2001
are 1A and 0.5A, respec-
tively. The
HWD2001'
s lower current limit allows the use
of a physically smaller inductor in space-sensitive
applications. The
HWD20012
features a circuit that elimi-
nates noise due to inductor ringing. In addition, the
HWD20012
offers a selectable current limit (0.5A or 1A)
for design flexibility.
PFM Control S c heme
A unique minimum-off-time, current-limited, pulse-fre-
quency-modulation (PFM) control scheme is a key fea-
ture of the
HWD20011/HWD2001/HWD20012
. This scheme
combines the high output power and efficiency of a
pulse-width-modulation (PWM) device with the ultra-low
quiescent current of a traditional PFM (
Figure 1
). There
is no oscillator; a constant-peak-current limit in the
switch allows the inductor current to vary between this
peak limit and some lesser value. At light loads, the
switching frequency is governed by a pair of one-shots
that set a typical minimum off-time (1μs) and a typical
maximum on-time (4μs). The switching frequency
depends upon the load and the input voltage, and can
range up to 500kHz. The peak current of the internal N-
channel MOSFET power switch is fixed at 1A
(
HWD20011
), at 0.5A (
HWD2001
), or is selectable
(
HWD20012
). Unlike conventional pulse-skipping DC-DC
converters (where ripple amplitude varies with input
voltage), ripple in these devices does not exceed the
product of the switch current limit and the filter-capaci-
tor equivalent series resistance (ESR).
S ync hronous Rec tific ation
The internal synchronous rectifier eliminates the need
for an external Schottky diode, thus reducing cost and
board space. During the cycle off-time, the P-channel
MOSFET turns on and shunts the MOSFET body diode.
H
High-Effic ienc y, Low-S upply-Current,
Compac t, S tep-Up DC-DC Converters
7
HWD20011
HWD2001
HWD20012
ONE-SHOT
TRIG
Q
F/F
R
S
Q
ONE-SHOT
TRIG
Q
CURRENT-LIMIT
AMPLIFIER
ERROR
AMPLIFIER
LOW-BATTERY
COMPARATOR
REFERENCE
REF
FB
V
IN
47
μ
F
47
μ
F
R1
200
R5
R6
DAMPING
SWITCH
22
μ
H
BATT
(
HWD20012
)
GND
LX
OUT
0.1
μ
F
0.1
μ
F
V
OUT
R4
LBI
LBO
R2
100k
R3
V
IN
V
OUT
CLSEL
(
HWD20012
)
SHDN
MINIMUM
OFF-TIME
ONE-SHOT
ZERO
CROSSING
AMPLIFIER
EN
MAXIMUM
ON-TIME
ONE-SHOT
P
N
Figure 1. Simplified Functional Diagram
相關PDF資料 |
PDF描述 |
|---|---|
| HWD2001EUA | High-Efficiency, Low-Supply-Current, Compact, Step-Up DC-DC Converters |
| HWD2108 | Dual 105 mW Headphone Amplifier |
| HWD2182 | 250mW Audio Power Amplifier with Shutdown Mode |
| HWF1682RA | L-Band GaAs Power FET |
| HWF1687RA | L-Band GaAs Power FET |
相關代理商/技術參數 |
參數描述 |
|---|---|
| HWD2001EUA | 制造商:未知廠家 制造商全稱:未知廠家 功能描述:High-Efficiency, Low-Supply-Current, Compact, Step-Up DC-DC Converters |
| HWD210 | 制造商:NTE Electronics 功能描述: |
| HWD2108 | 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Dual 105 mW Headphone Amplifier |
| HWD2111 | 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Dual 105mW Headphone Amplifier with Digital Volume Control and Shutdown Mode |
| HWD2119 | 制造商:未知廠家 制造商全稱:未知廠家 功能描述:350mWAudio Power Amplifier with Shutdown Mode |
發(fā)布緊急采購，3分鐘左右您將得到回復。