NCP1910GEVB ON Semiconductor, NCP1910GEVB Datasheet - Page 22

• Manufacturer Part Number: NCP1910GEVB
• Description: BOARD EVAL NCP1910DEMO-B-TLS
• Manufacturer: ON Semiconductor
• Series: -r

Specifications of NCP1910GEVB

• Design Resources: NCP1910 Schematic NCP1910GEVB BOM
• Main Purpose: DC/DC, Step Down
• Outputs And Type: 1, Non-Isolated
• Power - Output: -
• Voltage - Output: Adj down to 0.8V
• Current - Output: 3A
• Voltage - Input: 3 ~ 5.5 V
• Regulator Topology: Buck
• Frequency - Switching: 1MHz
• Board Type: Fully Populated
• Utilized Ic / Part: NCP1910
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: NCP1910GEVBOS

Equation 8.
Where:
Line Brown−Out Protection
(represented LBO pin) as receives a portion of the input
voltage (V
integrate the ac line ripple so that a voltage proportional to
the average value of V
input voltage conditions. A 7 mA current source lowers the
The multiplier voltage V
As shown in Figure 46, the Line Brown−Out pin
The main function of the LBO block is to detect too low
Ac line
Filter
EMI
♦
♦
♦
R
V
LBO pin, which is proportional to the rms input
voltage,
current I
R
V
I
SENSE
CS
M
M
LBO
is the sense current proportional to the inductor
is the external multiplier resistor connected to
pin, which is constant.
in
). As V
is the input voltage signal appearing on the
L
V
as described in Equation 13.
M
+
C
in
in
is a rectified sinusoid, a capacitor must
4 V
C
in
LBO
is applied to the brown−out pin.
CTRL
R
M
V in
V
I
M
CS
R
M
R
* V
LBOL
LBOU
+
is generated according to
V
LBO
4 V
Figure 45. The Multiplier Voltage Pin Configuration
CTRL(min)
LBO
Figure 46. The Line Brown−Out Configuration
CTRL
R
2
M
I
CS
* V
Modulation
PFC Duty
I
V
LBOH
LBO
CTRL min
Vdd
V
LBOT
2
(eq. 8)
http://onsemi.com
V
LBO comp.
LBO(clamp)
22
Also, due to the V
is squared, the transfer function and the power delivery is
independent from the ac line level. The relationship between
V
LBO pin voltage when a brown−out condition is detected.
This is for hysteresis purpose as required by this function.
be above the internal reference voltage, V
typically). In this case, the output of the LBO comparator
V
V
V
LBOcomp
CTRL
LBOcomp
R
In nominal operation, the voltage applied to LBO pin must
11
M
♦
♦
M
S
R
voltage of Operational Trans−conductance Amplifier
(OTA), as described in Equation 17.
voltage of V
PFC current modulation.
L
V
V
directly limits the maximum input power capability.
BO
reset
CTRL
CTRL(min)
and power delivery will be depicted later on.
I
Q
M
is low.
is the control voltage signal, the output
R
M
in
is not only the minimum operating
CTRL
t
LBO(blank)
2
feed−forward feature, where the V
reset
C
M
but also the offset voltage for the
t
LBO(window)
reset
LBOT
PFC_BO
(1 V
LBO