Okay, let's explain in detail the principle of this commonly used wireless charge launch end chip and the basic composition and workflow of its typical application circuit map. It is important to emphasize that complete and detailed circuit maps usually require reference to the official data manual of the chip, but its rationale and core components are common。
Core principles: electromagnetic sensing
The core function of the xkt901 chip: xkt901 is an integrated wireless charge launcher whose main function is:
The oscillator: generates a baseline oscillation signal. Driver: magnify oscillation signals to sufficient power to drive external power switches (mosfet). Power control & frequency reconciliation: to adjust its own drive frequency or space ratio (depending on the specific pattern) by detecting the signal strength of the feedback from the receiving end (usually modified on the magnetic field) and thus stabilize the power required. For example, when the receiving end needs more power, it “notifies” the launching end to increase output. Alien detection: critical safety! Xkt901 (complementing external components) continuously monitors the energy consumption and harmonious vibration at the launch end. If a metal is placed (coin, key, etc., rather than compatible receivers), the equivalent parameters of the coil change and energy consumption can increase exceptionally. Xkt901 detected this anomaly, which would immediately stop power transmission and prevent the risk of alien overheating. Fault protection: provides heat, pressure, flow protection, etc. Xkt901 make-up of typical application circuits for the wireless charge transmitter end (text description)
A typical wireless charger launch endway based on xkt901 consists mainly of:
Power input: usually from the usb 5v power adapter vin (e. G. 5v) and gnd (local). Xkt901 chip: main controller chip. Key quotes (typical): power switch mosfet (q1, q2) lc resonating circuits: current detection resistance (rsense): self-propelled circuits (cbot1, d1 or cboot2, d2): enter filter cap (cin): chip to cap (cvcc): status indicator (led1, led2): other possible components: simple frame diagram (text version connection)
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| usb 5v input | xkt901 chip | mosfet semi-bridge |
|vin(+)|->vcc|q1(high side)|---+
|gnd(-) |-- |gnd |
+-----------------------------------------------------------------------------------------------------------------------------------
out1 -------------
cin (filtration) |out2---->gate q2|++txcoil+cr|
+-|| (vin-gnd) | fb/adj | led+ | - - - - +
cvcc (departure) led2----- led---
+-|| (vcc-gnd) | \ \ \/ \ \ / changed magnetic field
| cp1 - -+ | (connecting to gnd) |
cp2 - - + |
++ - - - ++ - - ++
| + - - - - - - +
| diodes (d1, d2) (electrical feedback loop)
i'm sorry.
+ - - - | cboot capacitors
cboot1, cboot2
+-+The receiving end is activated by a brief description of the workflow with access to compatible receiving devices (cell phones). The receiving end sends a signal (including power requirements, identification, etc.) to the transmitter by means of a magnetic field. When xkt901 receives the signal, the drive is turned on and broken through the out1 and out2 alternation drivers q1 and q2. Q1 and q2 interpolate to generate high frequency communication voltage (vin square wave) at lx1 and lx2 (both ends of the circle). Lc harmonisation road (tx coil + cr) turns the square wave "filtration" closer to the sine wave and creates a strong and concentrated change magnetic field in space by coupling it with current sensing. The receiving circle senses a changing magnetic field, generating communication electricity. The receiving end will communicate electrical currents in direct currents, charge the equipment and continuously reciprocate to the launching end by magnetic field (e. G., the size of the receiving power). Xkt901 monitors currents through rsense via fb-led feet (representing the currents in the ejection loop). This signal is used to light a light of the appropriate colour according to the working state of the chip (on-board, charging, full, faulty). Important hints
I hope this detailed explanation in chinese will help you understand the principles and working methods of xkt901 wireless chargers! To obtain accurate circuit maps, it is important to find official technical information。
