HV9150K6-G データシートの表示（PDF） - Supertex Inc
部品番号
コンポーネント説明
メーカー
HV9150K6-G Datasheet PDF : 15 Pages
| |||
HV9150
The frequency of the oscillator is set by the external resistor
RFREQ, and this frequency is inversely proportional to the
value of RFREQ. Its characteristic is shown in the fOSC vs
RFREQ diagram.
1
fOSC = 4 • RFREQ • C
where C = 4.75pF
Voltage Reference (VREF)
The voltage reference is used by the comparator to compare
with the feedback voltage and the boost converter output.
This device provides the options of using either its internal
voltage reference or an external voltage reference.
Charge Pump Converter (CP mode)
A 3x charge pump converter is integrated into this device
to provide a 5V to 12V rail for the gate driver. It can be
activated by setting CP_EN to ground. A 3.3V supply is
more common and easily available for digital logic systems;
however, this voltage level is less desirable for driving a high
voltage MOSFET to obtain a lower ON-resistance for better
efficiency.
In order to reduce the number of supply rails used in the
system, an internal two stage charge pump converter is
added, which can boost the 3.3V supply voltage to 8.0V. A
8.0V gate driver output will outperform a 3.3V gate driver
by far and substantially improves the ON-resistance of the
external MOSFET.
The internal voltage reference provides a stable 1.25V with a
tolerance of ±2.5%. With the use of ±1% tolerance feedback
resistors, the output can be achieved with a tolerance of
±4.5%. In order to use the internal voltage reference, the
EXT_REF pin must be connected to ground.
The charge pump input can operate with an input voltage
from 2.7V to 4.5V. Its input and output are connected to the
VLL and VDD pins, respectively.
XNN
XFF
If the output voltage of the boost converter is required to
have high precision and tight tolerance, the external voltage
reference can be used to achieve that purpose. The external
reference voltage must be between 0.5V and VLL -1.4V, and
connect to the EXT_REF pin. A single low to high transition
must be presented at the EN pin to trigger the device to
select an external voltage reference. If no enable control
signal is available in the application, this signal can be easily
mimicked by a simple RC circuit.
VIN
EXT_REF
GND
EXT_REF
GND
Voltage
Reference
Internal
External
Voltage Connection Reference
Gate Driver (GATE)
The MOSFET gate driver of this controller is specially
designed to be able to drive the gate of the external MOSFET
up to 12V. A high pulse voltage will help to minimize the
ON-resistance of the external MOSFET transistor. A lower
ON-resistance improves the overall efficiency and heat
dissipation.
This gate driver is powered by the supply voltage VDD
which can be generated by either the internal charge pump
converter (CP mode) or the external power supply (LDO
mode), depending on the available voltage supply rail of the
application.
QUE
Three Times (3X) Charge Pump Converter
Linear Regulator (LDO mode)
In some applications, efficiency may be a key factor, and
higher voltage rails such as 5V, 6V, 9V or 12V may be
available in the system. The internal charge pump converter
cannot operate with these voltage levels because of the
maximum output voltage limit of the charge pump converter.
At the same time, these voltage levels are high enough to
provide an adequate supply for the gate driver.
Under this circumstance, an internal linear regulator is used
to replace the charge pump converter. This linear regulator
input can accept voltage from 5.0V to 12.0V, and generates
a 3.3V output to supply to the internal circuit. This linear
regulator can be activated by setting CP_EN to VLL.
In a scenario when the device is operating in LDO mode and
in shutdown state (EN = ”0”), the voltage at VLL is undefined.
In order to wake up the controller device, a voltage above
2.7V has to be presented at the enable pin (EN).
FB Ground Return Switch (FB_RTN)
Any DC/DC controller requires a feedback from the output
to monitor its operation so that it can regulate its output
accordingly. A simple resistor network is used in conjunction
with a feedback ground switch as a feedback path. The
purpose of this feedback ground switch is to save power
consumed by the feedback resistor network when the
controller is disabled. This function is quite useful for power
saving especially for battery operated applications.
Doc.# DSFP-HV9150
NR031914
Supertex inc.
6
www.supertex.com
Share Link: 