feature

4-channel balanced transformerless (BTL) driver

3-channel PWM input direct-coupled type, including internal filter.

Separate supply voltages (PVCC1: CH1 and CH2, PVCC2: CH3 and CH4)

Built-in input pin select function for channel 4

Built-in operational amplifier

Built-in energy saving function

Built-in thermal shutdown circuit (TSD) operating range: 4.5~13.2V

typical application

Compact Disc Player (CDP) Video Disc Player (VCD) Other Disc Media

illustrate

FAN8040G3 is a single-chip integrated circuit, suitable for 4-channel motor driver for driving tracking actuator, Compaq focusing actuator, trolley motor, spindle motor disk player system.

absolute maximum ratio

Note:

Pages: 1 When mounted on 76.2mm x 114mm x 1.57mm PCBs ("phenolic resin material").

Page: 1Power displosion reduces 16.6mw/c for using above ta=25℃

Page: 1Do not exceed pd and soa ("safe operating area")

application information

1. Power saving function

The power saving function is also performed on the PS (pin20). The truth table is as follows:

The bias circuit is enabled when PS (pin 20) is high (above 2V). On the other hand, when PS (pin20) is low (below 0.5V), the bias circuit is disabled.

When CAPA (pin 3) is low, turn on CAPA (pin 25) as shown.

2.TSD (thermal shutdown) function

The 4-channel BTL driver output circuit will mute when the chip temperature rises above 175°C. The hysteresis temperature of the TSD circuit is 25°C.

4. Balanced Transformerless (BTL) Drivers (CH1, CH2 and CH3) The CH1, CH2 and CH3 driver components are composed of internal filters, VI converters and output power amplifiers.

The internal primary filter consists of a 25uA source/source current source and a forward/reverse control switch.

Convert the "forward/backward" digital signal to an analog signal as shown.

If the forward input signal is high level (avobe 2.4V) and the reverse input signal is low level (below 0.5V), the forward current source switch s1 and the reverse current source switch S2 are turned on and off respectively .

This causes the internal capacitor C1 to charge, creating a current source of 25uA, resulting in the filter output VA increasing with an internal time constant of 2.5usec.

The time constant is

Wherein, R is 100 [㏀], and C is 25 [pF]. The output voltages VOUTF and VOUTR of the power amplifier are as follows

5. Channel 4 driver (spindle motor driver)

Channel 4 driver consists of input amplifier with input selection switch, VI converter and output power amplifier.

The voltage VREF is the external reference voltage given by the bias voltage at pin 26 in the figure.

The input signal VIN through CH4IN (pin24) is amplified by 100K/100K times and then fed to the next amplifier. And amplify the amplified voltage by R2/R1 times, and then feed it into the level shift circuit.

The level shift results in current flow due to the difference between the input signal and the internal power supply reference (PVCC/2). The resulting currents are fed into the driver buffers as +∏I and +∏I.

If the gain needs to be changed, CH4CAPA (pin 25) can be used. It is controlled by SW (pin3) input signal.

When the switch (pin 3) is high, the input voltage (VIN) is applied to CH4CAPA (pin 25).

Typical performance characteristics

Typical Application Circuit