psf2115 ETC-unknow, psf2115 Datasheet - Page 83

• Manufacturer Part Number: psf2115
• Description: Isdn Adapter Circuit Ipac
• Manufacturer: ETC-unknow

Figure 26
The transmitter of the PSB 2115 IPAC is identical to that of the well known PEB 2086
ISAC-S, hence, the line interface circuitry should be similar. The external resistors
(24 ... 33 ) are required in order to adjust the output voltage to the pulse mask (nominal
750 mV according CCITT I.430) on the one hand and in order to meet the output
impedance of minimum 20
on the other hand.
The S-bus receiver of the PSB 2115 is designed as a threshold detector with adaptively
switched threshold levels. Pin SR1 delivers 2.5 V as an output, which is the virtual
ground of the input signal on pin SR2.
The S-bus receiver of the PSB 2115 is symmetrical, which allows for a simple external
circuitry and PCB layout to meet the I.430 receiver input impedance specification.
Semiconductor Group
(CONF : AMP = O)
(CONF : AMP = 1)
Equivalent Internal Circuits of Receiver and Transmitter Stages
50 k
50 k
IPAC
IPAC
2.5 V
2.5 V
+
+
-
-
50 k
50 k
40
40 k
20
20 k
(transmission of a binary zero according to CCITT I.430)
k
k
ITS09678
SR1
SR2
SR1
SR2
83
2.1
2.1
V
V
< _
13.4 mA
IPAC
Functional Description
ITS09631
PSB 2115
PSF 2115
SX1
SX2
11.97