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TELEFUNKEN Semiconductors
U3750BM
One Chip Telephone Circuit
Description
TELEFUNKEN microelectronic's one chip telephone circuit, U 3750 BM, is BICMOS integrated circuit that performs all the speech and line interface functions required in an electronic telephone set, the tone ringer, the pulse and DTMF dialling with redial, a keyboard interface with the possibility to interface with an external microcontroller using the internal serial bus, and a power supply for peripherals.
Features
D Adjustable dc slope characteristic D Adjustable automatic line length receiving and sending gain control (not used in DTMF) with the possibility of fixed gain (PABX)
D Four ringing tones adjustable without external
components
D Internal speed up circuit permits a faster charge of
VCC and VRAM capacitors
D D D D
Adjustable dynamic impedance Stabilized power supply for peripherals Confidence level during pulse and DTMF dialling Receiving amplifier for dynamic or piezo-electric ear pieces symmetrical and 40 kW in asymmetrical) suitable for dynamic, magnetic, piezo-electric or electret microphone
D Logic bounce elimination D Pulse dialling 66/33 or 60/40 or DTMF dialling selectable by programming pin
D Adjustable flashing duration D Pause function D Confidence tone (440 Hz) D Last number redial up to 23 digits D Standard low-cost ceramic 455 kHz D Binary data input in serial mode D Test-mode capability
D High-impedance microphone inputs (80 kW in
D Dynamic limiting in sending (anticlipping) prevents
distortion of line signal and sidetone
D Ringing balanced output in HVMOS for higher power
capability
Benefits
D Low number of external components D High quality through one chip solution
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U3750BM
Block Diagram
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TELEFUNKEN Semiconductors
U3750BM
Pin Description
Pin 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Symbol C4 C3 FLASH DC/FV OL RESET TEEIN SHEN NC VRAM VCC VL OSCAB EC Function Keyboard input Keyboard input Flashing selection Dialling selection (33/66 pulse, 40/60 pulse or DTMF) Open line output Output reset Test pins Test pins Not connected RAM and internal logic supply Power supply for peripherals Line voltage Test pin Extra current for peripherals or can be used to dissipate power for high line current applications. Test pin Ground Not connected Line length AGC adjustment Bias adjustment Electronic self input DC characteristic slope adjustment Microphone input Pin 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 Symbol MIC2 ZAC EM/FILT MOD EM/MF ACL E2 E1 NC REC ZAL OUT1 OUT2 VIR CK PAIR BEAT MF C1 C2 C6 C5 Function Microphone input Dynamic impedance adjustment First sending stage output Modulator output Second sending stage input and DTMF input Anticlipping time constant adjustment Receiver output Receiver output Not connected Receiver input Sidetone network Buzzer output Buzzer output Ringing supply Ceramic input (455 KHz) Adjustment between two pairs of ringing frequencies Beat adjustment of each pair of ringing frequencies DTMF output Keyboard inputs Keyboard inputs Keyboard inputs Keyboard inputs
15 16 17 18 19 20 21 22
TESTR GND NC AGA IREF SELF RGAB MIC1
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U3750BM
Application Circuit
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Absolute Maximum Ratings
See application circuit Parameters DC line voltage Pin 36 DC line current Pin 36 Conversation line voltage Pin 12 Pulse duration, t = 20 ms Conversation line current Pin 12 Power dissipation, Tamb = 55C Junction temperature Ambient temperature range Storage temperature range Symbol VIR IR VL VL IL Ptot Tj Tamb Tstg Value 35 30 15 17 150 1 125 -25 to +55 -55 to +155 Unit V mA V V mA W C C C
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TELEFUNKEN Semiconductors
U3750BM
Symbol RthJA Value 70 Unit K/W
Thermal Resistance
Parameters Junction ambient
Electrical Characteristics
f = 1 kHz, fclock = 455 kHz, RE = 20 kW, Tamb = 25C, unless otherwise specified, Q (Resonance factor) = 3100, L1 = 6.1 mH, C1 = 21 pF, CO = 268.5 pF, R1 = 5.5 W. All resistances are specified at 1%, all capacitance at 2%.
Parameters Line voltage normal Line voltage operation
Stabilized voltage
Test Conditions / Pins IL = 8 mA IL = 15 mA IL = 28 mA IL = 60 mA figure 3 IL = 8 mA, ICC = 0.6 mA IL 28 mA, ICC = 2.1 mA figure 3
Symbol VL
Min. 2.9 4.1 6.4 12.3 2.0 3.3
Typ. 4.5
Max. 3.6 4.9 7.3 13.7
Unit V
w
VCC
2.5 3.5
V 3.7
Transmission Sending gain
VMI = 2 mVRMS (note 1) IL = 28 mA (GS max) IL = 60 mA (GS min) AGC IL = 28 to 60 mA figure 3 Psophometric sending noise VMI = 0, IL = 28 mA figure 3 Attenuation gain during VMI = 2 mVRMS, dialing IL = 28 mA figure 3 Microphone input figure 3 impedance (Pins 22-23) Common mode rejection IL = 28 mA ratio figure 3 From transmission to IL = 28 to 60 mA dialing mode figure 3, Pin 25 Dynamic limiter CACL = 470 nF, (anticlipping) RACL = 6.8 MW IL = 20 mA Output voltage swing IL 28 mA, (peak-to-peak value) VMI = 8 mVRMS figure 3 Overdrive dynamic range IL 28 mA figure 3 Line distortion (on 600 W) IL 28 mA VMI = 4.6 mVRMS VMI = 8 mVRMS VMI = 80 mVRMS figure 3
GS
DGS
47 39.5 -6
48 41 -7 -73
49 42.5 -8 -68
dB
dBmp dB
AS
63
70 CMRR Step -100
120 80 +100
kW dB mV
w w w
3.0
2.5 3.6
Vpp 4.2
5
dB
3 5 5
%
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Parameters Available current Test Conditions / Pins Close switch S4 IL = 28 mA IL = 60 mA figure 3 Pin 14 VL = 0.3 VRMS IL = 28 mA (GR max) IL = 60 mA (GR min) IL = 28 to 60 mA figure 4 VL = 0V, IL = 28 mA figure 4 Pin 29-30 IL = 15 mA, VR = 2.8 Vpp IL = 28 mA, VR = 5.5 Vpp IL = 60 mA, VR = 5.0 Vpp figure 4 VR = 50 mVRMS, IL = 28 mA figure 4 Pin 29-30 IL = 28 mA figure 4 Pin 29-30 IL = 28 mA figure 3 VL = 0.3 VRMS IL = 28 and 60 mA figure 4 Measured at pin VIR figure 5 figure 5 VIR = 18 V Load = 10 kW figure 5 Pin 38 grounded Pin 38 open Sweep frequencies Leakage current Pin 39 grounded Pin 39 open VIR = 30 V IIL at VIL = 0 V Pins 38 and 39 figure 5 Symbol
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Min. 7.0 35 Typ. 8 40 Max. Unit mA
Reception Receiving gain GR = VR/VL AGC Psophometric receiving noise Receiving distortion
GR
DGR
10 2.5 -6
11 4 -7
12 5.5 -8 -65
dB
dBmp
3 3 3 45 65 85
%
Receiver output impedance
W
Receiver output offset
-650
+650
mV
Sidestone (VR/VM) Z line matching impedance
36 580 660
40 750
dB
W
Ringer Turn on voltage Turn off voltage Current consumption without load Output voltage swing Output tone frequencies
VON VOFF 9.5
16 10.5 1.2
18.0
V V mA Vp
1.5
VOUT
VIR-2 1458 1166 547 438 4.0 9.1 5
Hz
Hz
mA
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Parameters Test Conditions / Pins DTMF generation Pin 4 grounded Tone frequency accuracy VRAM = 3.5 V (confidence tone included) Low group tone level (Note 2) (depends on external Measured on 600 W components) IL = 28 mA figure 3 High group tone level (Note 2) (depends on external Measured on 600 W components) IL = 28 mA figure 3 Preemphasis (depends on (Note 2) external components) Measured on 600 W IL = 28 mA figure 3 DTMF distortion (depends (Note 2 and note 3) on external components) Measured on 600 W IL = 28 mA, 300 < f < 3400 Hz figure 3 DTMF transmission time DTMF interdigit time Transmission mute tmMF Confidence tone Only by serial bus FCT frequency Tone level (depends on Measured on 600 W external components) IL = 25 mA figure 3 Symbol Min. -0.4 -10 -8
U3750BM
Typ. Max. +0.25 -6 Unit % dBm
-8
-6
-4
dBm
1
2
3
dB
3.5
%
tMF tIMF
80.2 89.2 169.4 440.9 -9
82.4 89.2 171.6
ms ms ms Hz dBm
Note 1: sending gain: GS = VL/VMI with the values of RAG1 and RAG2 (figure 3) so the maximum gain is at 28 mA and the minimum gain is at 60 mA. Note 2: For DTMF measurements, close switches S1 and S3 and select each group of frequencies on the keyboard. Note 3: The level of each harmonic on line is under the limited curve given below with the filter components value chosen for the test.
Figure 1
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U3750BM
-30
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dBm ( 600W )
-40
-50
-60 0.1
93 7831 e
1
10 f ( kHz )
100
1000
Figure 2
DTMF distortion
Figure 3 Test circuit
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TELEFUNKEN Semiconductors
U3750BM
Figure 4 Test circuit
Figure 5 Test circuit
S5 (Pin 38) ON ON OFF OFF
S6 (Pin 39) ON OFF ON OFF
Pair of Frequencies (Hz) 1458/1166 1458/1166 547/438 547/438
Sweep Frequency (Hz) 4 9.1 4 9.1
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Electrical Characteristics of Logical Part
fclock = 455 kHz (other specifications as under electrical characteristics) Parameters VRAM Speed-up off threshold Speed-up on threshold Logic operating voltage in normal mode IRAM Oscillator on Leakage Inputs: C1, C2, C3, C4, C5, C6, DC/FV, FLASH Keyboard pins: C1, C2, C3, C4, C5, C6 Internal pull down Output current FLASH, DC/FV Internal pull-up current IPV Leakage current Timing and frequency Reset time tr (see figure 6 and 7) Clock start-up time ton Time line break generating a reset: tlb Debounce time, te RESET output (with 390 W series) Output low current Output high current OL output Output low current Output high current MF output High impedance Test Conditions / Pins IL = 8 mA IL = 15 to 70 mA Symbol VSOFF VSON
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Min. 2.4 1.9
Typ. 2.75 2.2 2.5 3.5
Max. 2.9 2.3
Unit V V V V
VRAM = 3.5 V Input voltage low, VIL Input voltage high, VIH
0.8 VRAM
800 300 0.2 VRAM
mA mA
V V
VIL = 3.5 V VIH = 0 V VIL = 0 V VIH = 3.5 V
15 0.8 0.5
50 2.5 5 1
mA mA mA mA
ms ms ms
In mode 60/40 In mode 66/33 and DTMF mode
30 33 5 290 319 14 15.4 300 330 34 37.4
In mode 60/40 In mode 66/33 and DTMF mode In mode 60/40 In mode 66/33 and DTMF mode
24 26.4
ms ms ms ms
VOL = 2.5 V VOL = 0.5 V VOL = 0.5 V
IOL IOH IOL IOH
0.25 0.25 2 1
1.2 1.2 20 4 0.5 350 550 550 350 1 1
mA mA
mA
mA mA mA mA mA mA mA mA
VOHI = 1.4 V FL = L, FH = H, VOH = 3.5 V FB = L, FH = H, VOH = 0 V FB = H, FH = L, VOH = 3.5 V FB = H, FH = L, VOH = 0 V VIL = 0.5 V VIL = 3.0 V
150 200 200 150
CK Input Low input leakage High input leakage
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Parameters Serial bus (see figure 12) Pulse width clock Pulse width enable signal Set-up time data to clock Hold time data from clock Enable time Time between two transmissions Pulse dialing (OL) Dialing pulse frequency Test Conditions / Pins Symbol twl, twh tel, teh tset up te tRRN In mode 60/40 (Pin 4 tied to RESET) In mode 66/33 (Pin 4 not connected) TOL tb tm tIDOL 830 813 [n@100 + 30] [n@98.8 + 22] 89.5 98.5 102.5 239.5 263.5 274.0 109.5 120.5 125.0 830 813 846 3116 3075 3012 Min. 2 2 0 100 0 900
U3750BM
Typ. Max. Unit
ms ms ms ms ms ms
10 10.11 100 98.9 60 66 40 33 833 816.5 (n@100) + 32 (n@98.9) + 24.2 92 101 105 242 266 277 112 123 128 832 815.5 848.5 3118 3077 3110 Hz Hz ms ms ms ms ms ms ms ms ms ms
Dialing pulse period Break time Make time Interdigit time Transmission mute: tmol = (tm + tb) @ n + tm1 n pulses dialling Flash pulse Flash pulse duration
Transmission mute
Pause time
Pin 3 to GND Pin 4 to RESET Pin 3 to GND Pin 4 to NC Pin 3 to GND Pin 4 to GND Pin 3 to NC Pin 4 to RESET Pin 3 to NC Pin 4 to NC Pin 3 to NC Pin 4 to GND Pin 3 to RESET Pin 4 to RESET Pin 3 to RESET Pin 4 to NC Pin 3 to RESET Pin 4 to GND In mode 60/40 In mode 66/33 In mode DTMF In mode 60/40 In mode 66/33 In DTMF mode
tfl
ms
tmfl
Tp
ms
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U3750BM
Power-on Reset and Pin RESET
To avoid undefined states of the device when it is powered on, an internal reset clears the control logic. When the power supply rises above the internal reference level, the pin RESET goes to high during trt. After a line break longer than tlb, a reset is generated. A short line break (< tlb) does not affect the reset. Power on reset timings (t > tlb).
1)
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Pin RESET
It is the power on reset output. In test mode, it permits to force the IC U 3750 BM in permanent DTMF dialing by applying a negative voltage (test schematic figure 3).
Data Acquisition
Input data is derived from any standard matrix keyboard (15 keys) or from a remote microcontroller.
VRAM > VSON at t = 0 . . . . . . . . . a)
Trt = Tr + T on . . . . . . . . . . . . . . . . . . . . . . b)
Keyboard
The keyboard is connected to the IC by six pins, (see figure 8). Its matrix is triangular.
a)
b)
Figure 6
2)
VRAM < VSON at t = 0 . . . . . . . . . a)
Figure 8
Keyboard inputs to the U 3750 BM
Trt = T (VRAM to VS off) + Tr + T on . . . . b)
Internal pull down resistors (typical value: 120 kW) are connected to the inputs Ci. A push button is made by a short-circuit of two pins among the six. Entries are scanned every 12 ms or 13.2 ms and go to the logical state 1 during this scanning. The scanning is inhibited as soon as a calibrated linebreak is produced at the OL output. The scanning-cycle has eight phases: six of them are reserved for the scanning of the six pins, the two others are kept for the reset of the logic keyboard (T0) and the acquisition (T7). A push button is valid, if it is unique and if it's pressed long enough (see table of pressed and released push buttons). Every acquisition time, T7, the input code is decoded into 5 bits (with or without a pressed push button). The microprocessor can read it as soon as the logic keyboard has set a flag, tested about every 800 ms and which indicates that a pushbutton has been correctly detected. Rev. A1: 16.07.1996
a)
b)
Figure 7
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Table 2 The scanning principle
U3750BM
2.2 ms 2.2 ms 2.156 ms 22 ms 13.2 ms
Keyboard clock Ti except T0, T1, T7 T1 T0 or T7 Scanning cycle T0: T7:
2 ms 2 ms 1.956 ms 22 ms 12 ms
reset of the logic keyboard acquisition of the code present at the keyboard
Scanning
Push button
Figure 9 The scanning principle
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U3750BM
Timing of a Push Button
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The information from a pressed push button or released push button is taken into account if it is still present during at least two sampling times, T7.
Table 3 Timing of a push button
Clock Keyboard 2 ms, 2.2 ms Minimum time - push button on Minimum time - push button off
Min. 14 15.4 24 26.4
Typ. 24 26.4 24 26.4
Max. 34 37.4 34 37.4
Unit ms ms ms ms
The entries are debounced on both the leading and trailing edges for 34 ms or 37.4 ms according to the value of the keyboard clock, and so the time remains less than 40 ms. At this time the information can be processed. If the information is still present after more than 40 ms, it is only taken one time.
Serial Bus
The remote microcontroller is connected to the IC by 4 pins: C2, C3, C4, C5 (see figure 10).
Figure 10 Connection of the microcontroller to the U3750BM
C2 transmits the data, C3 the clock, C4 the enable signal, and C5 indicates the state of the dialer: C5 = 0, dialer is busy C5 = 1, dialer is free Data is serially shifted in a 5-bit register during the positive going transition of the clock pulse. The positive going transition of the enable signal validates the transmission.
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U3750BM
Figure 11 Timing of the serial bus
Code Entries Table
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 1 1 1 1 0 0 0 0 1 1 1 1 0 0 0 1 1 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 0 0 1 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 0 1 0 1 * 1 2 3 4 5 6 7 8 9 0 A B C D # 16 R flash Redial Confidence tone Micro inhibition Pause 23
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Dialer
The IC includes a dialing circuit for either pulse dialing or dual tone multifrequency dialing. The dialer transmits the codes decoded by the logic keyboard on the outputs OL and MF.
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on the dialing. The code A is filtered and corresponds to eleven pulses.
Dialing
As soon as the code is detected by the logic keyboard and written in RAM, it can only be loaded in the dialer if the dialer is not occupied and a pause is not generated.
Mode Selection
The choice of dialing is made by the tri-state-level on the DC/FV Pin FV DC = Z FV DC tied to pin RESET FV DC = 0 pulse dialing in 66/33 ms pulse dialing in 60/40 ms DTMF dialing calibrated
Pulse Dialing
The output which provides control signals for proper timing in pulse dialing is pin, OL. The dialling starts with a make time (see figure 12).
When the circuit is in pulse mode, it is possible to change over to DTMF dialing with the " * " key. The code " * " is sent in line. The circuit returns in pulse mode after a reset condition or after a flash pulse (see figure 14).
Dual tone Multifrequency Dialing
The output pin, MF, provides the multifrequency signal to transmit in line. This signal results from the sum of two frequency pulses modulated and requires a filter to compose a dual sine wave. The frequencies are chosen in a low group and a high group. Table 3 shows the frequency tolerance of the output tones for DTMF signalling. In manual dialing or in redial, output tone is timed with a fixed duration.
Dialing Codes
The dialing codes are the numeric keys 0 to 9, and the non numeric keys A, B, C, D, *, #. All are stored in RAM. The codes A, B, C and D can be only transmitted by the serial bus. In pulse dialing, the code #, B, C and D have no effect
Table 4 Frequency tolerance of the output tones for DTMF signaling
Standard Frequency Hz Low Group 697 770 852 941 High Group 1209 1336 1477 1633
Tone Output Frequency Hz 697.8 768.6 848.9 940.1 1210.1 1338.2 1477.3 1636.7
Frequency Deviation % +0.12 -0.18 -0.37 -0.10 +0.09 +0.17 +0.02 +0.22 Hz +0.85 -1.42 -3.12 -0.92 +1.11 +2.23 +0.27 +3.69
Tone output frequency when using a 455 kHz ceramic.
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TELEFUNKEN Semiconductors
U3750BM
Figure 12 Timing diagram for pulse dialing
Figure 13 Timing diagram for DTMF dialing
Figure 14 Timing diagram for mixed mode dialing
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U3750BM
Flash Control
Detecting a "R" code produces either a short timed line break (< 200 ms ) or long timed line break (>200 ms) at the OL output. For the duration of the flash, it is not possible to take information from the keyboard. Flash signifies that the circuit executes a particular work as a dialing, a redial, or a pause function, and the code "R" is lost and not used. The flash pulse resets the read address counter and does not erase the data storage, so later redial is possible. The flash duration is programmed by the FLASH pin (Pin 3) and depends on the selection of the tri-state-level pin (Pin 4). Mutes (transmission mute and dialing mute) become active high from the beginning of the line break. Timings explains this. According to these timings and what has previously been said, a second pulse flash could only follow the first one 810 ms or 850 ms later. Consequently the "R" entry remains inhibited during a time less than 1 second.
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Microphone Inhibition
Like the confidence tone, it is a flip flop function activated through the serial bus by the code 21 (in decimal).
RAM
Organization The RAM is 32 words of 5 bits and is organized in two parts: one for the data storage and the other for the working RAM. Safeguard The safeguard is guaranteed by an external capacitor. If VRAM decreases under the data retention supply voltage, the redial function is forbidden. After the reset of the circuit, a test is executed on VRAM in order to ensure the redial validity. Data storage Storage, overflow and erasing are realized through three address counters. The written address counter (P1) points out the location where the code will be stored. At each storage, P1 is incremented by one. As each code is recalled from the RAM for line dialing, the read address counter (M1) is incremented by one to select the RAM location of the next code to be recalled. Consequently, the difference between the contents of P1 and of M1 represents the number of codes that have been written into the RAM but not yet converted into line dialing. The third counter (P2) gives the real capacity of the redial register.
Pause Function
A pause separates the dial sequence. It is used for waiting for a dial tone. A pause code takes one position in the RAM like a digit. However, if the circuit executes a pause and if another pause code is entered, the storage of the second one does not occur. Furthermore, the pause running is aborted. Duration of the pause is given in electrical characteristics for the following configuration: digit, pause, digit, and consequently takes into account the interdigit.
Redial features
Capacity If more than 23 codes are entered into the RAM memory, overflow results and the excess codes replace the data in the lower numbered RAM locations. In this event, automatic redial is no longer possible. Storage Storage pertains to the dialing codes 0 to 9, *, #, pause, A, B, C and D. It is independent of the dialing mode (pulse dialing or DTMF dialing).The storage generally contains the last digits transmitted. Use of redial The use of redial is always possible except if the content of the RAM is empty (P2 = 0). This happens when the RAM supply is not high enough , when an overflow occurred, or when previously an erroneous use of the redial occurred (start of manual dialing not equal to the content of the RAM). Rev. A1: 16.07.1996
Particular Functions
After the reset, the particular functions are cleared. The state of the circuit is no confidence tone, no microphone inhibition.
Confidence Tone Output
When the data entries are derived from the serial bus, a pulse frequency modulation corresponding to a 440 Hz sine wave can be generated on the output MF by transmitting the confidence tone code which is 20 (in decimal). The function confidence tone is a flip-flop function. 18 (20)
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If the redial is ordered after a manual dialing the redial is executed according to the digits already transmitted in line. The redial is effective if the comparison digit-by-digit of all digits is correct. It is not produced if the comparison is incorrect or if the number of digits exceeded the last capacity of the redial. During redial, entry codes are accepted.
U3750BM
between these two codes: code 16 always erases the redial, code 23 inhibits a later redial if it is transmitted after or before dialing codes. The following examples illustrates this. Transmitted Codes 123 16 Redial 123 Redial 123 Redial 123 Redial 123 Redial 123 Redial 23 16 23 R R 4 4 16 23 On Line 123 -nothing 123 - 1234 4 1234 - 123R - 123R 123
Procedure with *
Storage does not pertain to the "*" code and the codes entered after it when the manual dialing starts with a numeric code or A, B, C, D, #, or pause codes. If the dialing starts with the "*" code, all codes can be stored. Note: the "#" code is treated for storage like a number.
Procedure with flash
The flash pulse does not reset the content of the RAM. Example: 1 2 3 R Redial a 1 2 3 R 1 2 3 Redial a 1 2 3
Special Case
When the overflow flag is set and when the written address counter becomes equal to the read address counter, the codes are not stored.
Erasing redial
The erasing is possible through the serial bus with the decimal codes 16 and 23. There is not much difference
Dimensions in mm
Package: PLCC 44
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U3750BM
Ozone Depleting Substances Policy Statement
It is the policy of TEMIC TELEFUNKEN microelectronic GmbH to
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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
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Rev. A1: 16.07.1996

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