βUTB0010

The βUTB0010 is a monolithic subscriber line interface circuit (SLIC) for telephone exchanges, made by IPRS Băneasa [1].

The I.P.R.S. Băneasa Full Line Condensed Catalog (1990) lists the βUTB0010 and βUTB0011, marked as preliminary data, as monolithic integrated circuits for telephone electronic central offices, the two differing by a minor change in the pin assignment [1]. The linear section has a 2-to-4 wire converter, a receive buffer and an emission booster; the gain is set externally with a semipot, the loop current is limited and the longitudinal induction is suppressed [1]. The digital section has a subscriber line sensing pin that controls the bias circuitry, reducing the standby power when the line is on hook or short-circuited; the power down state output is TTL compatible, the chip select and read/write pins are TTL/CMOS compatible inputs and data is a three-state TTL/CMOS compatible input/output pin, for direct interfacing on the data bus of the control system; two open collector outputs, B1 and B2, controlled by the CS, R/W and D pins, command two external high-voltage transistors that drive the phone ring bell [1].

The catalog gives an operating temperature of −25…+70 °C (storage −25…+125 °C), a supply voltage of at most ±12 V, a frequency response (200 Hz…4 kHz) within ±0.5 dB, a transhybrid rejection (f = 1 kHz) of at least 30 dB, a longitudinal rejection of at least 45 dB and an output capability of at least 40 mA on B1 and B2 [1]. Pins (MP-117, top view), βUTB0010: 1 open collector B2, 2 GND (linear + digital), 3 receive input, 4 L1 telephone line, 5 L2 telephone line, 6 CF frequency compensation, 7 emission output, 8 VA− negative power supply (linear), 9 PD power down TTL output, 10 VA+ positive power supply (linear), 11 VD positive power supply (digital), 12 S subscriber line sensor, 13 CS chip select, 14 R/W read/write, 15 D data, 16 open collector B1; the βUTB0011 has 1 GND digital and 2 GND linear, the other pins being the same [1].