參數(shù)資料
型號(hào): AIC164227XTB
廠商: Analog Integrations Corporation
英文描述: 3-Pin One-Cell Step-Up DC/DC Converter
中文描述: 3引腳單細(xì)胞升壓型DC / DC轉(zhuǎn)換器
文件頁(yè)數(shù): 10/14頁(yè)
文件大?。?/td> 251K
代理商: AIC164227XTB
AIC1642
10
APPLICATION INFORMATION
GENERAL DESCRIPTION
AIC1642 PFM (pulse frequency modulation) control-
ler ICs combine a switch mode regulator, N-channel
power MOSFET, precision voltage reference, and
voltage detector in a single monolithic device. They
offer extreme low quiescient current, high efficiency,
and very low gate threshold voltage to ensure start-
up with low battery voltage (0.8V typ.). Designed to
maximize battery life in portable products, and
minimize switching losses by only switching as
needed service the load.
PFM controllers transfer a discrete amount of en-
ergy per cycle and regulate the output voltage by
modulating switching frequency with the constant
turn-on time. Switching frequency depends on load,
input voltage, and inductor value, and it can range
up to 100KHz. The SW on-resistance is typically 1.9
to 2.2
to minimize switch losses.
When the output voltage drops, the error compara-
tor enables 100kHz oscillator that turns on the
MOSFET around 7.5us and 2.5us off time. Turning
on the MOSFET allows inductor current to ramp up,
storing energy in a magnetic field. When MOSFET
turns off that force inductor current through diode to
the output capacitor and load. As the stored energy
is depleted, the current ramp down until the diode
turns off. At this point, inductor may ring due to re-
sidual energy and stray capacitance. The output ca-
pacitor stores charge when current flowing through
the diode is high, and release it when current is low,
thereby maintaining a steady voltage across the
load.
As the load increases, the output capacitor dis-
charges faster and the error comparator initiates cy-
cles sooner, increasing the switching frequency.
The maximum duty cycle ensure adequate time for
energy transfer to output during the second half
each cycle. Depending on circuit, PFM controller
can operate in either discontinuous mode or con-
tinuous conduction mode. Continuous conduction
mode means that the inductor current does not
ramp to zero during each cycle.
+
VIN
SW
V
OUT
EXT
I
D
I
OUT
Isw
Ico
I
IN
I
PK
I
IN
V
EXT
I
SW
I
OUT
T
DIS
Charge Co.
V
SW
Discharge Co.
I
D
t
Discontinuous Conduction Mode
相關(guān)PDF資料
PDF描述
AIC164227XTR 3-Pin One-Cell Step-Up DC/DC Converter
AIC164227ZBG 3-Pin One-Cell Step-Up DC/DC Converter
AIC164227ZTB 3-Pin One-Cell Step-Up DC/DC Converter
AIC164227ZTR 3-Pin One-Cell Step-Up DC/DC Converter
AIC164230XBG 3-Pin One-Cell Step-Up DC/DC Converter
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
AIC164227XTR 制造商:AIC 制造商全稱:Analog Intergrations Corporation 功能描述:3-Pin One-Cell Step-Up DC/DC Converter
AIC164227ZBG 制造商:AIC 制造商全稱:Analog Intergrations Corporation 功能描述:3-Pin One-Cell Step-Up DC/DC Converter
AIC164227ZTB 制造商:AIC 制造商全稱:Analog Intergrations Corporation 功能描述:3-Pin One-Cell Step-Up DC/DC Converter
AIC164227ZTR 制造商:AIC 制造商全稱:Analog Intergrations Corporation 功能描述:3-Pin One-Cell Step-Up DC/DC Converter
AIC164230XBG 制造商:AIC 制造商全稱:Analog Intergrations Corporation 功能描述:3-Pin One-Cell Step-Up DC/DC Converter