onsemi CM1641-04D4

Overview

CM1641-04D4 from onsemi is a 4-channel low-capacitance dual-voltage ESD protection array in an 8-lead UDFN package (1.7 mm × 1.35 mm, 0.4 mm pitch), featuring three ±8 kV IEC61000-4-2 low-voltage channels (Pins 1–3) and one ±15 kV high-voltage channel (Pin 4), with 1.5 pF typical input capacitance per LV channel and 53 pF for the HV channel - deployed on high-speed data lines in portable USB and audio interfaces.

For engineers reviewing the CM1641-04D4 datasheet, pinout, applications, or equivalent options, key selection criteria include channel-specific ESD robustness (±8 kV vs. ±15 kV), differential leakage (<100 nA at 3.3 V), dynamic resistance (0.59–1.20 Ω), clamp voltage performance (+9.64 V / −1.75 V), and thermal stability of capacitance across −40°C to +85°C operating range.

Technical Context

The CM1641-04D4 integrates three low-voltage Zener-based ESD clamps (6.8–9.2 V breakdown) and one high-voltage Zener (14.6–17.7 V) on a shared substrate with Pins 5–8 tied to VN (negative rail) and DAP grounded. It operates without external bypass capacitors due to internal rail-to-rail clamping architecture.

Each LV channel exhibits <0.02 pF capacitance mismatch and stable 1.2–1.5 pF input capacitance from −30°C to +65°C at 1 MHz; the HV channel delivers 53 pF input capacitance at 2.5 V bias, optimized for supply-rail protection while maintaining signal integrity on adjacent high-speed I/Os.

Key Specifications

Pinout & Package

CM1641-04D4 uses an 8-lead UDFN package (Case 517BC, 1.7 mm × 1.35 mm, 0.4 mm pitch) with exposed die attach pad (DAP) requiring PCB ground connection. Pins 5–8 are internally connected to VN (negative supply rail) and share substrate grounding.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPD4E001DRYR and ESD7L5.0DT5G, CM1641-04D4 uniquely combines triple LV signal protection, dedicated HV rail clamping, and VN-rail integration in one UDFN-8 footprint - reducing component count by ≥3× and enabling compact, thermally robust designs for dual-rail interfaces.

Availability

CM1641-04D4 is available at Aetrix Electronics and suitable for USB 2.0 interface protection, smartphone audio jack ESD hardening, and industrial sensor hub interface applications requiring stable component supply and long-term lifecycle support.

Supply support for CM1641-04D4 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

onsemi (formerly ON Semiconductor) is a global semiconductor supplier delivering energy-efficient, intelligent power and sensing solutions for automotive, industrial, cloud, medical, and IoT applications.

The CM1641-04D4 belongs to onsemi's ESD protection portfolio designed specifically for high-density, high-speed interface protection in portable and industrial electronics with stringent capacitance and reliability requirements.

FAQ

What is the maximum operating temperature range for CM1641-04D4?

The CM1641-04D4 is rated for continuous operation from −40°C to +85°C, as specified in Table 3 of its datasheet. This range covers standard industrial and consumer environments. Operation outside this range may affect ESD performance, leakage current, and capacitance stability - all parameters were characterized within this window, and extended temperature validation is not provided for CM1641-04D4.

Can CM1641-04D4 be used to protect a 5 V supply rail?

Yes - the HV channel (Pin 4) of CM1641-04D4 has a breakdown voltage of 14.6–17.7 V and is rated for DC voltages up to 14.5 V, making it suitable for clamping transients on 5 V rails. However, it is not intended as a primary overvoltage protector; its role is ESD suppression. For sustained overvoltage, a dedicated 5 V TVS or regulator remains necessary alongside CM1641-04D4.

How is the die attach pad (DAP) of CM1641-04D4 connected in the circuit?

The DAP on CM1641-04D4 must be soldered to a solid PCB ground plane. It is electrically connected to internal ground and serves both thermal dissipation and EMI suppression functions. The datasheet explicitly states "Connect to Ground" and shows DAP as GND in the pin description table - floating or unconnected DAP degrades ESD performance and increases junction temperature under repeated strikes.

Does CM1641-04D4 require external bypass capacitors?

No - CM1641-04D4 eliminates the need for external bypass capacitors, as stated in its features list and confirmed by electrical architecture: internal Zener clamps provide rail-to-rail protection with inherent capacitance filtering. Adding external caps may cause resonance or degrade high-frequency ESD response; the design was validated without them per IEC61000-4-2 testing conditions.

What is the leakage current specification for CM1641-04D4 at 3.3 V?

At 3.3 V applied to LV channels (Pins 1–3) with VN = 0 V and temperature ranging from −30°C to +65°C, CM1641-04D4 specifies a maximum leakage current of 100 nA. This value is measured per Table 4 and ensures minimal impact on battery-powered circuits - critical for always-on sensor interfaces and portable audio subsystems using CM1641-04D4.