l3037 STMicroelectronics, l3037 Datasheet - Page 10

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

L3037
In case of U.S. application based on L3035 the
external components can be calculated suppo-
sing:
- Rfeed = 400
EXTERNAL COMPONENTS (for US. Application)
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) Loaded Line.
(4) Not Loaded Line.
(5) Transistor characteristic: P
(6) V
(7) For details see AN496.
(8) RST and RSR wattage should be calculated according to the power cross test specification. (When PTC become open circuit the entire
(9) 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 ;
(10) Suggested Rp type are 2W wire wound resistors or thick film resistors on ceramic substrate.
(*) ex: BD140; MJE172;MJE350....(SOT32 or SOT82 package available also for surface mount).
10/22
CCOMP
PTC (2)
RST (2)
RSR (2)
CVDD
RA (1)
CH (1)
Name
CVSS
RREF
CSVR
ZA (1)
ZB (1)
QEXT
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.
T = 2.5ms.
power cross voltage will appear across RSR and RST).
RF 400
ZAC
RS
RF
RT
RING
Rp
D1
Fuse function should be included if PTC are not used.
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 Freq. Comp.
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 (5)
Protection Resistor
Relay Kickback Clamp Diode
(RF typ. value = 400 ).
DISS
Function
= 1W (typ. depending on application); h
RING
: Ring Frequency, T: relay response time. Typical value obtained for V
P
Resistor should be splitted in two parts keeping at least 20
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] (6)
CRG = 25 A/(V
180] 2 f
< 15
10 to 50K
10 to 50K
30 to 80
200
200
(9)
(9)
FE
- Zs = 900 + 2.12 F
- Zl = 1650 // (100 + 5nF) Loaded Line
- Zl = 800 // (100 + 50nF) Not Loaded Line
- Rp = 62
RING
@ fo = 250KHz
RING
RING
(10)
25; I
/25 A)cos[-2 f
Formula
) 390nF
RING
(6)
C
100mA; V
sin[2 f
(7)
(7)
RING
CEO
RING
T
T
60V; f
between TIP/RING terminals and
T
82.5K + (5K + 100pF) (3)
15MHz.
RING
40K + (5K + 1nF) (4)
3.9nF 20%
39K + (180K//55nF)
39K + (180K//55nF)
330nF 20% 63VI
390nF 20% 6VI
33K 1W 5%(8)
33K 1W 5%(8)
= 100Vrms, f
100nF 20%
100nF 20%
100pF 20%
Typ. Value
20% 15VI
200
200
23.7K 1%
20% 60VI
2.76K 1%
6.2K 1%
6.2K 1%
4M
1N4148
100pF
680nF
4.7 F
20%
10
62
(*)
5%
2W
2W
RING
100V
= 25Hz;