6

Typical applications

6.1

Rotary resolver

In closed-loop motor control systems, a preferred way to read out the shaft’s angular position is the rotary

resolver. It essentially exists of one primary reference winding plus two secondary windings, the sin- and cos-

winding in the stator. Since the primary winding is typically powered through a rotary transformer, no brushes

or rings are needed. This increases the overall reliability and robustness of the resolver and makes it perfectly

suitable for harsh environments with varying temperature and in oily, dusty, or humid surroundings.

Closed-loop motor control systems help to navigate factory robots and to maneuver vehicles in autonomous

parking mode. The TSB582 manages the power amplification to pilot the primary winding of a resolver device as

can be seen in Figure 33.

6.2

Design requirements

The shown schematic essentially takes a low voltage sinusoidal input signal with 3.3 V peak-to-peak at 1 kHz to

20 kHz and transforms it into a differential output of 24 V peak-to-peak with high current capability to drive the

primary winding of a resolver in bridged mode.

Figure 33. Rotary resolver excitation amplifier

-

TSB582

TSB582

-

STM32

Rin1

Rfeed1

Rin2

Rfeed2

Cfeed1

Cin1

TSB582

3V3_MCU

24 V

24 V

Vcc/2

Vcc/2

Vcc/2

20 kHz

12 Vpp

typ. impedance

sin

12 Vpp

2/2

1/2

power

3.3 Vpp

DAC

100 n

22 p

10 kΩ

10 kΩ

10 kΩ

36 kΩ

100 ... 500 Ω

The gain resistance should be adapted to the desired input / output voltage levels:

AV=VoutVin= 12 Vpp3.3 Vpp=3.63−

(7)

Rfeed1=AV⋅ Rin1= 3.63−⋅10 kΩ=36.36− kΩ ≈ 36 kΩ 

(8)

AVfinal=3.6, error= 1.01 %

(9)

TSB582

Typical applications

DS13378 - Rev 2

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