iC-RC1000

SIN/COS SIGNAL SAFETY MONITOR IC

Rev C2, Page 9/14

Single-ended application

Signals referring to ground with double amplitude (400 bis 600 mV) can also be monitored; for this purpose the

negative input must be kept in the permissible common mode range (e.g. at VCC/2).

51kΩ

GND

OK

ERR

VCC1

VCC2

iC-RC1000

PSIN

NSIN

PCOS

51kΩ

NCOS

PSIN

ERR

OK

PCOS

VCC2

VCC1

GND

GND

Figure 4: Single-ended application

Monitoring of phase shift

The phase shift between SIN (PSIN-NSIN) and COS (PCOS-NCOS) can be monitored only indirectly, what

leads to limitations. The following table shows the phase error tolerance for different input frequencies. Any

larger phase shift results in an error message.

1 Hz

10 Hz

100 Hz

1 kHz

10 kHz

100 kHz

200 kHz

300 kHz

400 kHz

500 kHz

0.8 Vpp ±18 °

±18 °

±18 °

±18 °

±20 °

±33 °

±48 °

±75 °

*

*

1.0 Vpp ±34 °

±34 °

±34 °

±34 °

±36 °

±50 °

±65 °

*

*

*

1.2 Vpp ±9 °

±9 °

±9 °

±9 °

±10 °

±15 °

±22 °

±25 °

±35 °

±45 °

Table 5: Permissible phase error ∆PHI between SIN and COS for different input frequencies (without series

resistors); *) No error message (OK = 1 and ERR = 0)