overview
VPS8703 is a DCDC isolated switching power supply integrated controller suitable for full bridge topology. The bridge drive mode has less transformer windings and low cost. satisfy
6.5V~30V application, strong compatibility. When the current is too large, the clamp limits the current of the power tube, which not only ensures that the chip itself works in a safe area, but also protects the peripheral devices from the impact of high current.
Its operating frequency can be set through the CLK pin (it is the default frequency when floating), and a dead time t BBM
is designed between the two drivers
, which avoids the common phenomenon,
It can also reduce the drain-source voltage when the power tube is turned on, reducing the switching loss.
The ON or OFF of the chip can be controlled through the EN pin. When EN is pulled to a high potential (it is pulled to a high potential by itself when it is suspended), the chip operates normally; EN is pulled to a low potential
, the chip stops working to achieve ultra-low standby power consumption.
1 Features
Full
bridge topology
High
integration, simple peripheral
Built -
in 30V/0.25Ω NMOS
Built -
in 30V/0.60Ω PMOS
6.5-30V input voltage range
Input
surge voltage up to 40V
Programmable
switching frequency
Enable
shutdown function
Sustainable
short-circuit protection, over-temperature protection, self-recovery
Chip
operating temperature -40℃~+125℃
ESOP8 enhanced heat dissipation package
2 Fields of application
CAN\RS-485\RS-232\SPI\I2C and other low-power isolated power supplies
Process control
Precision
instruments\medical instruments
Distributed
power supply\radio power supply\telecom power supply
Low
noise isolated USB power supply
Low
noise filament power supply
IGBT gate drive power supply
3 Description
VPS8703 is a microcontroller designed for small size, low standby power consumption
Transformer driver designed for power isolation power supply, its periphery only needs to match
Simple input and output filter capacitors, isolation transformers and rectifier circuits, namely
It can realize 6.5~30V input voltage, various output voltages and output power
Isolated power up to 15W.
VPS8703 integrates two N-channel power MOSFETs and two
A P-channel power MOSFET, and form a bridge connection. on chip
The external integrated oscillator provides a pair of high-precision complementary signals, which can effectively ensure that the two
The high symmetry of the power MOSFET drive avoids the circuit
The process is biased.
VPS8703 integrates frequency modulation function and multiple protection methods.
According to different application requirements, the frequency adjustment can be realized, and the internal design has
The high-precision dead zone control circuit ensures that no
Common phenomenon; integrated over-current detection protection and over-temperature protection to avoid
The device will be damaged under abnormal conditions such as short circuit of power supply output.
