TS4604

Application information

Doc ID 17913 Rev 1

23/31

To switch the TS4604 back to standby, the voltage across the divider R1, R2 has to be lower

than 1.25 V - VHyst

× R1/(R1 + R2). The ESV can be an external voltage or simply the

power supply voltage PVcc_LD/HD.

6.9

2nd order Butterworth low-pass filter

The TS4604 can also be configured as a low-pass filter to be driven directly by a DAC

output. It can be used, for example, as a 2nd order low-pass filter, with either a differential

input or a single-ended input.

Figure 51 and Figure 52 depict these two kinds of application and represent a multiple

feedback 2nd order low-pass filter.

An AC-coupling capacitor should be added to block any DC component from the source,

which helps to reduce the output DC offset to a minimum.

Example 2nd-order multi-feedback filter in differential mode

Figure 53 shows a filter in differential mode with a cut-off frequency at 30 kHz (configured as

per the values in Table 8, which proposes various filter options using a differential input).

Figure 51.

Multi-feedback filter with

differential input

Figure 52.

Multi-feedback filter with single-

ended input

Rin

Rin

Rfd

Cin

Cin

Rfd

R1

R1

C1

C1

C2

Vout

Vin-

Vin+

AM06145

Rin

Rfd

Cin

R1

C1

C2

Vout

Vin-

AM06146