Renesas HC55185CIMZ96

Overview

HC55185CIMZ96 from Intersil is a VoIP ringing subscriber line interface circuit (RSLIC) designed for analog POTS line interface in short-to-medium loop applications. It delivers balanced/unbalanced ringing up to 67 VRMS, supports 100V high battery operation, achieves ≤13 dBrnC idle channel noise in forward active mode, and operates across 0°C to +85°C with 28-lead PLCC packaging. It serves as the core line driver in VoIP terminal adapters and cable modems.

For engineers reviewing the HC55185CIMZ96 datasheet, HC55185CIMZ96 pinout, HC55185CIMZ96 application, or HC55185CIMZ96 equivalent, key selection criteria include its 100V VBH rating, programmable transient current limit (40–100 mA), longitudinal balance of 53 dB (Grade C), low standby power (85 mW at VBH = −100 V), and compatibility with existing HC5518x designs.

Technical Context

The HC55185CIMZ96 implements a dielectric-isolated bipolar process enabling robust 100V operation and integrated ringing generation using sinusoidal or trapezoidal waveforms. Its dual-supply architecture separates low-noise analog signal paths (VCC/AGND/BGND) from high-voltage battery rails (VBH/VBL), with dedicated tip/ring amplifiers supporting both forward/reverse active and ringing modes via F2/F1/F0 control logic.

It integrates programmable DC loop current limiting (15–45 mA), transient current limiting (40–100 mA sink/source), ring trip detection (2.3–2.9 V threshold), and thermal shutdown with ALM output. The device maintains MTU-compliant open-circuit voltage (43–51.5 VDC tip-to-ring) and supports silent polarity reversal and pulse metering without external relays.

Key Specifications

Pinout & Package

HC55185CIMZ96 uses a 28-lead plastic leaded chip carrier (PLCC) package per JEDEC MS-026, with Pb-free (RoHS-compliant) matte tin terminations and moisture sensitivity level (MSL) 3. The exposed die pad is not present; thermal dissipation relies on PCB copper area under the body.

Key Features

Applications

Equivalent & Alternatives

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

Compared with HC55185AIMZ96, HC55185CIMZ96 trades industrial temp rating for cost efficiency in climate-controlled premises; compared with HC55185FCMZ96, it provides 15V higher VBH for longer loops and stricter GR-1089 surge margin-making it the optimal choice for new commercial VoIP hardware designs requiring full 100V capability.

Availability

HC55185CIMZ96 is available at Aetrix Electronics and suitable for VoIP gateways, cable modem telephony adapters, and VoDSL terminal units requiring stable component supply across multi-year production cycles.

Supply support for HC55185CIMZ96 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

Intersil (now part of Renesas Electronics) is a semiconductor manufacturer specializing in high-performance analog and mixed-signal ICs for communications, industrial, and power management applications.

The HC55185 product line was developed specifically for VoIP and broadband access equipment requiring integrated, high-voltage ringing SLICs with low noise, programmable supervision, and RoHS-compliant packaging.

FAQ

What is the maximum ringing voltage supported by HC55185CIMZ96?

The HC55185CIMZ96 supports an open-circuit balanced ringing voltage of 67 VRMS when configured for 100V VBH operation. This is measured with VRS input = 0.840 VRMS and meets ITU-T G.961 requirements for analog telephone line ringing. Unbalanced ringing delivers 33.5 VRMS under the same conditions.

Does HC55185CIMZ96 require external components for basic operation?

Yes, HC55185CIMZ96 requires external resistors to program key functions: TL pin resistor sets transient current limit (40–100 mA), RIL sets DC loop current (15–45 mA), RSH sets switch hook detect threshold (5–15 mA), and RS sets impedance matching. A non-polarized CFB capacitor (4.7 µF) and protection resistors (≥49 Ω) are also mandatory per the application circuit.

How does HC55185CIMZ96 achieve MTU compliance in low-power standby mode?

In low-power standby (mode 000), HC55185CIMZ96 maintains MTU compliance by regulating tip-to-ring open-circuit voltage to 43–51.5 VDC (at VBH > −60 V) and delivering 18–26 mA loop current. Internal switches and references hold tip near ground and clamp ring to −54 V typical, meeting FCC Part 68 Maintenance Termination Unit specifications without external circuitry.

Is HC55185CIMZ96 pin-compatible with earlier HC5518x devices?

Yes, HC55185CIMZ96 is functionally and pin-compatible with HC55181CIM and HC55182CIM per the product cross-reference table in FN4831 Rev 15.00. Application circuit modifications are minimal: RS changes from 210 kΩ to 66.5 kΩ, CFB from 0.47 µF to 4.7 µF, and addition of TL programming resistor-no PCB layout change required.

What thermal management considerations apply to HC55185CIMZ96 in PLCC packaging?

HC55185CIMZ96 in 28-lead PLCC has a typical θJA of 53°C/W. To maintain junction temperature below 150°C, ensure ≥2 in² of 2-oz copper pour connected to VBH and AGND pins beneath the package. Avoid placing heat-generating components nearby, and verify worst-case power dissipation (250 mW in ringing mode) against ambient + board thermal resistance.