U3761MB-T Datasheet, PDF (23/27 Pages) ATMEL Corporation – Universal Telephone IC - All Functions Integrated

U3761MB-T
Electrical Characteristics Tone Ringer
f_RCK = 4 kHz, V_RING = 20 V, T_amb = 25°C, reference point GND, unless otherwise specified
Parameters
Test Conditions
Symbol
Min.
Typ.
Max.
Unit
Supply current, outputs open
Switch-on threshold
Switch-off threshold
Ringing frequency
Range of external components for
R/C oscillator
V_RIAC = 20 V
V_RIAC, THA = open
V_RIAC
R = 150 kW, C = 1 nF
V_RIAC > V_RON
I_RING
V_RON
V_ROFF
f_1H
f_1L
C
R
2.1
3.8
mA
8
9
10
V
5.0
5.6
6.5
V
937
1010 1083
Hz
752
808
868
Hz
1000
2200
pF
50
330
kW
Audio sequence frequency
Output voltage swing
Turn-off delay
V_Ring = 25 V, C_out = 68 nF
See Figure 15
Note: Max. current into internal zener diode at pin VRING = 20 mA
f₂
11.5
12.5
14.0
Hz
V_out
21
23
V_pp
t_off
65
100
ms
Figure 16. Turn-off Delay Time
Volt
VRING
0
t
VRIAC
0
t
OUT
Melody
t
0
t_off
Note
The oscillator frequency is defined by R and C at pin RCK.
f_Osc » ₁----_.--₅---₉---₄-----_´-----_C------_´----_[-¹--_R------+-----₃---₈---₀----₉-----_W-----_]
The audio sequence frequency f₂ and the ratio of low frequency f_1L and high frequency
f_1H are derived from the oscillator by internal deviders. So f₂, f_1H and f_1L are given by:
f₂
=
f_--O----s--c-
320
;
f_1H
=
f_{--O----s--c- ;}
4
f_1L
=
f_--O----s--c-
5
For more information on adjusting ringer melody refer to the document “Application and
Adjustment Hints”.
23
4744A–CORD–09/03