Infineon Technologies PBL38620/2SOT

Overview

PBL38620/2SOT from Infineon Technologies is a bipolar Subscriber Line Interface Circuit (SLIC) for telephony line cards, providing constant-current loop feed up to 30 mA, programmable overhead voltage (POV), integrated ring relay driver, and on-hook transmission capability. It supports dual battery feed with automatic switching, delivers 44 V open-loop voltage at –48 V supply, and operates in 24-pin SOIC package for PBX and terminal adapter applications.

For engineers reviewing the PBL38620/2SOT datasheet, PBL38620/2SOT pinout, PBL38620/2SOT application, or PBL38620/2SOT equivalent, key selection criteria include loop current programmability, longitudinal balance compliance (Bellcore TR909), hybrid gain configuration, analog temperature guard behavior during transmission, and SLIC state control via C3/C2/C1 inputs.

Technical Context

The PBL38620/2SOT implements a fully integrated bipolar SLIC architecture with dual-battery feed control logic that autonomously selects between high- and low-voltage supplies based on loop resistance. Its hybrid function enables two-wire to four-wire and four-wire to two-wire voice frequency signal conversion without external transformers.

It features analog-based loop monitoring - including ground key detection, ring trip detection, and loop current sensing - all operating independently of digital control. The programmable POV adjusts signal headroom dynamically, while the internal bias current of RSN sets longitudinal impedance matching per IEC/ITU-T standards.

Key Specifications

Pinout & Package

Package: P-DSO-24-1 - 24-pin plastic dual small outline package, 300 mil body width, gull-wing leads, JEDEC MS-013AC compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar SLIC applications.

Compared with Si3210-D-GM and LE89316, the PBL38620/2SOT offers analog-programmable headroom and autonomous dual-battery switching without MCU dependency - critical for legacy-compatible, low-latency telephony systems where deterministic analog behavior is prioritized over digital configurability.

Availability

PBL38620/2SOT is available at Aetrix Electronics and suitable for Central Office line cards, PABX interfaces, and terminal adapters requiring stable component supply, long-lifecycle support, and proven field reliability in telecom infrastructure.

Supply support for PBL38620/2SOT includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Infineon Technologies AG is a German semiconductor manufacturer specializing in power management, automotive ICs, and wired communications solutions.

The FlexiSLIC product line was designed for cost-optimized, flexible analog line interface in PBX, CO, and CPE equipment - emphasizing low-power operation, analog supervision fidelity, and minimal external component count.

FAQ

What is the maximum loop current setting for PBL38620/2SOT?

The PBL38620/2SOT supports programmable loop current up to 30 mA via external RSN resistor. The internal bias current is 10 µA, so RSN = 10 µA × RSENSE sets the full-scale current; for 30 mA, RSENSE = 3.33 kΩ (standard E96 value 3.32 kΩ). This value is confirmed in Table 11 and Figure 12 of DS1.

Does PBL38620/2SOT support loop start signaling?

Yes, the PBL38620/2SOT is explicitly designed for loop start signaling, as stated in Section 1.3 of the datasheet. It integrates loop current detection, ground key detection, and ring trip detection - all required functions for reliable loop start supervision in PBX and CO applications.

Can PBL38620/2SOT operate without an external CODEC?

No - the PBL38620/2SOT is a SLIC only and requires an external CODEC or filter for two-wire/four-wire conversion. Section 1.3 states it works "in conjunction with either a conventional CODEC/filter or with a programmable CODEC/filter", such as SiCoFi PEB 2466. It lacks integrated A/D or D/A converters.

What is the purpose of the C3/C2/C1 control inputs?

C3, C2, and C1 are three binary inputs that define the SLIC's operating state per Table 2: e.g., C3:C2:C1 = 0:0:0 = open circuit, 0:0:1 = ringing, 0:1:0 = active (off-hook), etc. These pins directly configure internal switch matrices and bias paths - no software or clock required.