l3037 STMicroelectronics, l3037 Datasheet - Page 8

• Manufacturer Part Number: l3037
• Description: Subscriber Line Interface Circuit
• Manufacturer: STMicroelectronics

L3037
EXTERNAL COMPONENTS
Notes:
(1) These components can be removed and ZB pin shorted to GND when 2/4wire conversion is implemented with 2nd generation COMBO (EG.
(2) In case there is no necessity to recover the unbalance introduced by PTC tolerance pins TIP and STIP can be shorted togheter as pins
(3) Transistor characteristic: P
(4) V
(5) Defining RTTX + CTTX = ZTTX, RTTX and CTTX can also be calculated from the following formula: Z
(6) RST and RSR wattage should be calculated according to the power cross test specification. (When PTC become open circuit the entire
(7) In order to optimize the component count it is also possible to use only one resistor in series to the ringing generator. In this case RT = 0 ;
(8) Suggested Rp type are 2W wire wound resistors or thick film resistors on ceramic substrate.
(*) ex: BD140; MJE172;MJE350....(ST32 or SOT82 package available also for surface mount).
8/22
CCOMP
PTC (2)
RST (2)
RSR (2)
CVDD
RA (1)
CH (1)
Name
CVSS
RREF
CSVR
ZA (1)
ZB (1)
QEXT
CREV
RTTX
CTTX
RDC
RRG
CRG
CVB
CRT
CAC
TS5070FN)
RING and SRING. In this case also the R
protection connection. In this case PTC or fuse resistor (if used) can be placed in series to Rp.
Typical value obtained for V
power cross voltage will appear across RSR and RST).
RF 400
Fuse function should be included if PTC are not used.
ZAC
RS
RF
RT
RING
Rp
D1
For low power application (reduced battery voltage) BCP53 (SOT223 surface mount package) can be used.
: Max Ring Generator Voltage, f
Battery Filter
Positive Supply Filter
Negative Supply Filter
Internal Current Reference
Battery Ripple Rejection
Ring Trip & Ground-key Capacitor
DC Feeding Resistance
AC/DC Splitter
Protection Resistor Image
2 Wire AC Impedance
SLIC Impedance Balancing Network
SLIC Impedance Balancing Network
Line Impedance Balancing Network
AC Feedback Compensation
Trans-hybrid Loss Frequency
Compensation
Feeding Resistance for Ring Inj.
Feeding Resistance for Ring Inj.
Ring Input Resistor
Ring Input Capacitor
Positive Temp. Coeff. Resistor
Tip Buffer Sensing Resistor
Ring Buffer Sensing Resistor
External Transistor (3)
Protection Resistor
Teletax Cancellation Resistor
Teletax Cancellation Capacitor
Relay Kickback Clamp Diode
Polarity Reversal Transition Time
Programming
(RF typ. value = 400 ).
DISS
Function
RING
= 1W (typ. depending on application); h
= 100Vrms, f
RING
: Ring Frequency, T: relay response time.
P
Resistor should be splitted in two parts keeping at least 20
RING
= 25Hz; T = 2.5ms.
CSVR = 1/(6.28 * fp * 150K)
@ fp = 1.6Hz
CRT = (25/f
RDC = 10 * (Rfeed - 2Rp)
CAC = 1 / (6.28 * fsp * RDC)
@ fsp = 10Hz
RS = 50 * 2RP
ZAC = 50 * (Zs-2Rp)
ZA = 50 * (Zs-2Rp)
RA = 50 * 2Rp
ZB = 50 * Zl
CCOMP = 1 / [2 fo (100 Rp)]
CH = CCOMP
RRG = (V
180] (4)
CRG = 25 A/(V
180] 2 f
< 15
10 to 50K
10 to 50K
30 to 80
RTTX = 21.5 [Re (Zlttx) +2Rp]
CTTX = 1/(21.5 [–Im(Zlttx) fttx 6.28])
(5)
200
200
CREV =
(7)
(7)
FE
RING
@ fo = 250KHz
RING
RING
(8)
25; I
) (4)
V
/25 A)cos[-2 f
Formula
TR
) 390nF
RING
K
C
100mA; V
T
sin[2 f
; K = 2 10
RING
CEO
RING
T
T
(5)
-4
60V; f
FTTX
between TIP/RING terminals and
T
= 21.5 [Zlttx + 2Rp].
15MHz.
3.9nF 20%
330nF 20% 63VI
390nF 20% 6VI
33K 1W 5% (6)
33K 1W 5%(6)
100nF 20%
100nF 20%
220pF 20%
Typ. Value
20% 15VI
200
200
5.6nF 20%
23.7K 1%
20% 60VI
6.34K 1%
3.2K 1%
26K 1%
26K 1%
30K 1%
4M
1N4148
4K 1%
4K 1%
220pF
680nF
4.7 F
47nF
20%
10
40
(*)
5%
2W
2W
100V