TEMIC U4074B

U4074B
Tone Ringer Interface
Description
The U4074B is a monolithic integrated circuit that
contains all integral components of a ringing circuit for
telephone sets used in conjunction with a microcomputer.
The combination of a microcomputer and the U4074B
permits flexible programming of the ringing sequence
( melody), tone and volume control.
Ringing frequency detection takes place in the
microcomputer. The U4074B is responsible for the
interface to the line, driver stages for the piezoelectric
sound transducer, volume adjustment, amplitude
detection, voltage supply for the microcomputer and
other auxiliary functions.
Features
D Suitable for specifications FTZ 1TR2 and ETR 2
D Z-diode
D CMOS-compatible microcomputer interface
D 2-bit log. volume adjustment
D High-voltage bipolar technology, 30 V
D Amplitude detection
Benefits
D Rectifier bridge
D Supply voltage for microcomputer 3.5 @
v 1.5 mA
D DC operation possible
D mC controlled melody and volume
D Low number of external components
D Bridge push-pull output stage
47mF
22 mF
VB
2(3)
TH
130 kW
3(4) VDD 10 (12)
2f 4(5)
On/Off
a 0.8mF
(1)1 a
2.2 kW
Ringing signal
b
(16)14
Ȁ
+VB
VRef
Control
12(14)
O2
b
Ȁ
2f
+V B
Decoder and
DA converter
PIEZO
O1 Transducer
11(13)
93 7793 e
(15)13 GND 5(6)
A1
6(7) (9)7 Mel
VDC 8(10)
9(11)
A0
Volume
Figure 1. Block diagram and application circuit ( pin connections for SO16 in brackets )
TELEFUNKEN Semiconductors
Rev. A1, 06-May-96
1 (6)
Preliminary Information
U4074B
Pin Configuration
aȀ
1
16
NC
2
15
GND
3
14
O2
VB
TH
bȀ
13
4
O1
2f
5
12
VDD
A1
6
11
VDC
A0
7
10
VDC
NC
8
9
Mel
aȀ
1
14
VB
2
13 GND
TH
3
12 O2
2f
4
11 O1
A1
5
10 VDD
A0
6
9
VDC
Mel
7
8
VDC
94 7903 e
94 7904 e
Pin
1, 14
(1,16)
2 (3)
3 (4)
Symbol
4 (5)
5, 6
(6, 7)
7 (9)
8, 9
(10, 11)
10 (12)
11, 12
(13, 14)
13 (15)
(2, 8)
2f
A1, A0
aȀ, bȀ
VB
TH
bȀ
Function
AC ringing signal input
Mel
VDC
Output to charging capacitor
Comparator threshold adjustment input
Output for frequency detection
Digital volume adjustment input
Input for melody signal
DC supply diode connections
VDD
O1, O2
Microcomputer supply voltage
Outputs to the transducer
GND
NC
Ground
Not connected
via a 0.8 mF decoupling capacitor connected in series with
a 2.2 kΩ. resistor
3. The circuit possesses the following overload resistance at terminals a and b.The circuit can withstand
a voltage of 110 V with a frequency of 50 Hz at
terminals a and b for a maximum of 15 s.
4. Testing the circuit with the configuration shown in
figure 2 does not destroy the circuit under the
following conditions.
Charging voltage of surge capacitance: Vcs = 2 kV
Pulse shape: 10/700 ms
Pulse sequence: 30 s
Number of surges: 10
Polarity change after 5 surges
See figure 2.
Pin Description
Power supply aȀ and bȀ, Pin 1, 14
An ac ringing voltage is supplied to the inputs aȀ and bȀ
Smoothing Capacitors, Pin 2, 10
After rectification of the ac ringing voltage via the
integrated rectifier bridge, the pulsating DC voltage is
smoothed by the external capacitor ( 22 mF to 47 mF ) at
Pin 2 ( 3 ). The charging voltage is restricted to a
maximum of 30 V by an integrated Z-diode. A 47 mF
external capacitor of will smooth the regulated supply,
VDD, at pin 10 (12 ).
2 (6)
Preliminary Information
TELEFUNKEN Semiconductors
Rev. A1, 06-May-96
U4074B
15 W
25 W
a
10 mF
110W
2 kV
0.22 mF
Tone ringing
Figure 1
b
93 7575 e
Figure 2. Test circuit
Outputs O1, O2 Pin 11, 12
Supply Voltage VDD, Pin 10 (12)
The bridge push-pull outputs are used for direct
connection of a piezo electric sound transducer with a
typical value of 80 nF. The output stage transistors can
process up to 20 mA in both directions.
An external load, such as a microcomputer, can be
connected to VDD. This value of VDD is 3.5 V for a
maximum load current of 1.5 mA. VDD is highly resistive
and can block up to 6 V in call and idle states. The typical
value of the back-up capacitor is 47 mF.
ǒ
Ǔ
The output signal without load is 2
Ri
+
V (12,11 open
– 1
V (12,11) load
where Rload = 400 W
(VB - VDD – 3.5 V)
ā
ā
R load
Frequency Detection 2f, Pin 4 (5)
Volume Adjustment A1, A0
Pin 5 (6), 6 (7)
The ringing volume is adjusted by means of a 2-bit D/A
converter. The maximum volume is achieved with the bit
combination A1 (MSB) = 1 and A0 (LSB) = 1. The
volume can be reduced by approximately 35 dB (A) if a
bit combination of A1 = 0, A0 = 0 is supplied. The volume
is programmed by supplying a ground potential to these
inputs.
Frequency detection takes place in the microcomputer.
For this purpose, the output 2f supplies a square wave
signal with double ringing frequency to the
microcomputer. The output signal is CMOS-compatible.
This terminal is highly resistive in idle and call states.
Comparator Threshold Adjustment
TH Pin 3 (4)
The on/ off threshold of the 2f comparator can be adjusted
( terminal against ground respectively VDD ). To fulfill the
Bundespost specification this terminal should be open.
Melody, Pin 7 (9)
The melody input inverts the activation phase of the
bridge push-pull output stage. The input is CMOScompatible and suitable for processing ringing
frequencies.
TELEFUNKEN Semiconductors
Rev. A1, 06-May-96
VDC, Pin 8, 9
Decoupling diode for dc supply.
3 (6)
Preliminary Information
U4074B
Absolute Maximum Ratings
Reference point, Pin 13 ( 15), unless otherwise specified, Tamb = 25°C
Parameters
Symbol
Value
Unit
Supply current
Pin 1, 14 ( 1, 16 )
Is
50
mA
Output current
Pin 11, 12 ( 13,14)
I0
50
mA
Junction Temperature
Tj
125
°C
Ambient temperature
Tamb
–25 to + 60
°C
Storage temperature
Tstg
–40 to + 125
°C
Ptot
Ptot
860
400
mW
mW
Symbol
Value
Unit
RthJA
75
160
K/W
K/W
Power dissipation
Tamb = 60°C
DIP14
SO16
Thermal Resistances
Parameters
Junction ambient
DIP14
SO16
Electrical Characteristics
Tamb = –10 to 60°C, reference point is Pin 13 ( 15), unless otherwise specified
Parameters
Current consumption
Input voltage
Test Conditions / Pins
Pin 1, 14 (1, 16)
O1 = O2 = open
A1 = A0 = 0, VB = 15 V
IDD = –300 mA,
Pin 2 (3) open
Pin 1, 14 (1, 16)
on threshold
off threshold
Audio frequency
impedance
f = 300 to 3400 Hz,
Va,b = 1.5 Vrms
Output on resistance
I(O1, O2) =
Internal voltage limitation
IZ = 1 mA (Pin 2)
Supply voltage for
microcomputer
0.5 mA > IDD < 1.5 mA
Leakage current
Va , Vb , VB
Ȁ
Ȁ
"20 mA
v
VA1, VA0, VMelody 6 V
5.5 V VDD 6 V
0 V VDD 5.5 V
Min.
I
V
9.5
4.5
R
200
Typ.
Max.
Unit
1.1
1.4
mA
10.5
5.5
11.5
6.5
V
V
Ron
VZ
v 3.5 V
v v
v v
Symbol
kW
400
W
25
27
30
V
3.15
3.5
3.85
V
10
mA
I2f
IA0
IA1
I
IDD
Diode load current
100
10
80
4 (6)
Preliminary Information
mA
mA
TELEFUNKEN Semiconductors
Rev. A1, 06-May-96
U4074B
Order Information
Extended Type Number
Package
U4070B-FP
SO16
U4074B
DIP14
Remarks
Dimensions in mm
Package: DIP14
Package: SO16
TELEFUNKEN Semiconductors
Rev. A1, 06-May-96
5 (6)
Preliminary Information
U4074B
Ozone Depleting Substances Policy Statement
It is the policy of TEMIC TELEFUNKEN microelectronic GmbH to
1. Meet all present and future national and international statutory requirements.
2. Regularly and continuously improve the performance of our products, processes, distribution and operating systems
with respect to their impact on the health and safety of our employees and the public, as well as their impact on
the environment.
It is particular concern to control or eliminate releases of those substances into the atmosphere which are known as
ozone depleting substances ( ODSs).
The Montreal Protocol ( 1987) and its London Amendments ( 1990) intend to severely restrict the use of ODSs and
forbid their use within the next ten years. Various national and international initiatives are pressing for an earlier ban
on these substances.
TEMIC TELEFUNKEN microelectronic GmbH semiconductor division has been able to use its policy of
continuous improvements to eliminate the use of ODSs listed in the following documents.
1. Annex A, B and list of transitional substances of the Montreal Protocol and the London Amendments respectively
2 . Class I and II ozone depleting substances in the Clean Air Act Amendments of 1990 by the Environmental
Protection Agency ( EPA) in the USA
3. Council Decision 88/540/EEC and 91/690/EEC Annex A, B and C ( transitional substances ) respectively.
TEMIC can certify that our semiconductors are not manufactured with ozone depleting substances and do not contain
such substances.
We reserve the right to make changes to improve technical design and may do so without further notice.
Parameters can vary in different applications. All operating parameters must be validated for each customer
application by the customer. Should the buyer use TEMIC products for any unintended or unauthorized
application, the buyer shall indemnify TEMIC against all claims, costs, damages, and expenses, arising out of,
directly or indirectly, any claim of personal damage, injury or death associated with such unintended or
unauthorized use.
TEMIC TELEFUNKEN microelectronic GmbH, P.O.B. 3535, D-74025 Heilbronn, Germany
Telephone: 49 ( 0 ) 7131 67 2831, Fax number: 49 ( 0 ) 7131 67 2423
6 (6)
Preliminary Information
TELEFUNKEN Semiconductors
Rev. A1, 06-May-96