U3810BM Datasheet, PDF (24/31 Pages) TEMIC Semiconductors – Multi Standard Feature Phone Integrated Circuit

U3810BM
TELEFUNKEN Semiconductors
Power-on-reset and reset pin
The system (U3810BM + microcontroller) is woken up by
an initial condition:
– line voltage (VL)
– ringer
(THA)
– external supply (ESI)
To avoid undefined states of the system when it is powered
on, an internal reset clears the internal registers, and
maintains pin RESET low during trt.
1.) Power on in speed-up condition (VDD < VSON)
LINE
LVIO
SHUTDOWN
VDD
CO
RESETN
2.) Power on without speed-up (VDD > VSON)
Figure 11
LINE
LVIO
SHUTDOWN
VDD
CO
RESETN
24 (31)
Figure 12
937609
937610
Rev. A1: 19.01.1996