My Inquiry
My Account
onsemi SA85CA
- Part No.:
- SA85CA
- Manufacturer:
- onsemi
- Category:
- TVS Diodes
- Package:
- DO-204AC, DO-15, Axial
- Datasheet:
-
SA85CA.pdf
- Description:
- TVS DIODE 85VWM 137VC DO15
- Quantity:
- Payment:
- Shipping:
Inventory:9,846
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
SA85CA from Fairchild Semiconductor is a bidirectional 500 W transient voltage suppressor (TVS) diode in DO-15 package, designed for clamping ESD and surge transients in power and signal lines. It features a 85 V reverse stand-off voltage (VRWM), 94.4–104.0 V breakdown voltage (VBR), 137.0 V clamping voltage at 3.6 A peak pulse current, and operates up to +175 °C junction temperature.
For engineers reviewing the SA85CA datasheet, pinout, applications, or equivalent options, this page delivers verified electrical parameters, DO-15 terminal mapping, bidirectional clamping behavior, thermal derating curves, and direct alternatives for industrial power supply protection, automotive body electronics, and telecom interface surge hardening.
Technical Context
The SA85CA is a glass-passivated, bipolar junction TVS diode optimized for unidirectional or bidirectional transient suppression on DC power rails and low-frequency signal paths. Its fast response time (<5.0 ns for bidirectional operation) and low incremental surge resistance enable effective clamping of 10/1000 μs waveform surges up to 500 W.
It exhibits <1.0 μA reverse leakage at VRWM = 85 V, a 1.0 mA test current for VBR measurement, and thermal stability across –65 °C to +175 °C storage and operating ranges. The device complies with JEDEC surge testing standards using 8.3 ms half-sine wave pulses at ≤4 pulses/minute duty cycle.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Peak Pulse Power (10/1000 μs) | 500 W - sustains single high-energy surges without failure in industrial surge environments |
| Reverse Stand-off Voltage (VRWM) | 85 V - maximum continuous DC or RMS voltage before significant leakage begins |
| Breakdown Voltage (VBR) | 94.4–104.0 V at 1.0 mA - defines onset of avalanche conduction under transient stress |
| Clamping Voltage (VC @ IPPM) | 137.0 V at 3.6 A - limits downstream circuit voltage during full-rated surge event |
| Peak Pulse Current (IPPM) | 3.6 A - maximum non-repetitive surge current the device safely clamps |
| Reverse Leakage (IR @ VRWM) | ≤1.0 μA - ensures minimal standby power loss and signal integrity in high-impedance circuits |
| Junction Temperature Range | +175 °C max - supports operation in engine bay, power converter, and enclosed industrial enclosures |
Pinout & Package
SA85CA is housed in a DO-15 axial-leaded package with cathode band omitted (bidirectional configuration). Leads are tinned and suitable for wave or hand soldering with 0.375" lead length derating.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode (Lead 1) | Surge return path (bidirectional) | Connects to protected line; conducts during negative transients relative to cathode |
| Cathode (Lead 2) | Surge return path (bidirectional) | Connects to protected line; conducts during positive transients relative to anode |
Key Features
| Feature | Design Value |
|---|---|
| Glass-passivated junction | Ensures long-term reliability and stable VBR under humidity and thermal cycling stress |
| Fast response time | <5.0 ns turn-on for bidirectional transients - critical for protecting fast logic and analog inputs |
| Low incremental surge resistance | Minimizes voltage overshoot during high di/dt events, improving clamping precision |
| 500 W peak pulse rating | Meets IEC 61000-4-5 Level 4 (4 kV/2 Ω) surge immunity requirements with margin |
| DO-15 mechanical compatibility | Enables drop-in replacement in legacy board designs using standard axial footprint |
Applications
| Industrial Power Supply Protection | Automotive Body Control Module (BCM) |
|---|---|
Use Scenario: 24 V DC input rail in programmable logic controller (PLC) power entry subjected to load dump and inductive switching transients. IC Role / Device Role / Timing Role: Primary clamping element placed between input fuse and bulk capacitor to limit voltage excursion to <140 V. Use Value: Prevents overvoltage damage to upstream rectifier and downstream DC-DC controllers by clamping 500 W surges within 5 ns. |
Use Scenario: LIN bus transceiver power rail exposed to battery voltage spikes during jump-start or alternator load dump. IC Role / Device Role / Timing Role: Bidirectional TVS connected between VBAT and GND to suppress ±100 V transients per ISO 7637-2 Pulse 5a. Use Value: Maintains transceiver functionality by limiting rail voltage to 137 V while drawing <1 μA at nominal 12 V operation. |
| Telecom Line Interface Protection | Renewable Energy Inverter DC Link |
Use Scenario: RS-485 data line powered from local 12 V supply in outdoor base station cabinet subject to lightning-induced surges. IC Role / Device Role / Timing Role: Secondary protection stage after gas discharge tube (GDT), clamping residual energy before transceiver IC. Use Value: Provides sub-5 ns response to complement slower GDT, achieving combined clamping below 150 V at 3.6 A. |
Use Scenario: DC link between PV array and MPPT converter where voltage can reach 1000 V, but local transients require localized suppression. IC Role / Device Role / Timing Role: Parallel-mounted TVS on auxiliary 85 V bias rail supplying gate drivers and sensors. Use Value: Absorbs switching noise and coupling spikes without loading the 85 V rail due to <1 μA leakage at VRWM. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMBJ85CA (Bourns) | Same VRWM (85 V), same DO-214AA package; 600 W rating, lower VC (130 V), higher IPPM (4.6 A) | Better suited for higher-energy surge environments requiring tighter clamping | Select when PCB space allows SMC/SMB footprint and system requires >500 W margin |
| P6SMB85CA (Littelfuse) | Identical VRWM (85 V), DO-214AA package; 600 W rating, VC = 130 V, IPPM = 4.6 A, IR = 1.0 μA | Same performance envelope as SMBJ85CA; broader global distribution and longer production history | Preferred for high-volume industrial programs needing extended lifecycle assurance and dual-sourcing |
Compared with SA85CA, SMBJ85CA and P6SMB85CA offer higher pulse power (600 W) and lower clamping voltage (130 V), enabling improved protection margin in systems with tight voltage tolerances-though both require SMC/SMB layout changes versus DO-15.
Availability
SA85CA is available at Aetrix Electronics and suitable for industrial power supply protection, automotive body electronics, and telecom interface surge hardening requiring stable component supply, consistent DO-15 form factor, and proven 500 W surge capability.
Supply support for SA85CA 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
Fairchild Semiconductor was a U.S.-based semiconductor company specializing in power management, analog, and discrete components before its acquisition by ON Semiconductor in 2016. Its TVS portfolio emphasized ruggedness, consistency, and JEDEC-compliant surge performance.
The SAxxCA series was engineered specifically for cost-sensitive, high-reliability DC rail protection in automotive, industrial, and telecom infrastructure-prioritizing stable VBR, low IR, and DO-15 compatibility for legacy manufacturing.
FAQ
What is the clamping voltage of SA85CA at its rated peak pulse current?
The SA85CA has a maximum clamping voltage (VC) of 137.0 V when subjected to its rated peak pulse current of 3.6 A on a 10/1000 μs waveform. This value is measured per industry-standard test conditions and ensures predictable overvoltage limiting during surge events. The SA85CA maintains this clamping performance across its full operating temperature range up to +175 °C junction temperature.
Is SA85CA unidirectional or bidirectional, and how does that affect circuit placement?
SA85CA is a bidirectional TVS diode, indicated by the "CA" suffix, meaning it provides symmetrical clamping for both positive and negative transients. Unlike unidirectional variants, it has no cathode marking and connects across the protected line and ground without polarity sensitivity. This makes SA85CA ideal for AC-coupled lines, differential buses, or any application where voltage reversals may occur-no orientation check is needed during assembly.
What is the reverse leakage current specification for SA85CA at its 85 V stand-off voltage?
The SA85CA specifies a maximum reverse leakage current (IR) of 1.0 μA when biased at its rated reverse stand-off voltage of 85 V, measured at TA = 25 °C. This ultra-low leakage preserves signal integrity and minimizes standby power loss in high-impedance monitoring circuits or battery-backed systems. Leakage remains well below 5 μA even at elevated temperatures up to +125 °C.
Can SA85CA be used in place of SA85A in a design?
No-SA85CA and SA85A are not interchangeable. SA85A is unidirectional with a cathode band and only clamps positive transients; SA85CA is bidirectional with no polarity marking and clamps both polarities. Substituting SA85CA for SA85A introduces unnecessary conduction during normal negative excursions and may disrupt circuit biasing. Always match the "A" (unidirectional) or "CA" (bidirectional) suffix to the protection topology.
What package type and lead configuration does SA85CA use?
SA85CA uses the DO-15 axial-leaded package with 0.375" lead length, compliant with industry-standard through-hole mounting. Its leads are tin-plated copper, rated for 1.0 W steady-state dissipation at 75 °C ambient when mounted with specified lead length. No color band is present-consistent with bidirectional construction-and the device is mechanically identical to other SAxxCA family members for automated insertion and wave soldering.
SA85CA Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Package/Case:
- DO-204AC, DO-15, Axial
- Series:
- -
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Type:
- Zener
- Unidirectional Channels:
- -
- Bidirectional Channels:
- 1
- Voltage - Reverse Standoff (Typ):
- 85V
- Voltage - Breakdown (Min):
- 94.4V
- Voltage - Clamping (Max) @ Ipp:
- 137V
- Current - Peak Pulse (10/1000µs):
- 3.6A
- Power - Peak Pulse:
- 500W
- Power Line Protection:
- No
- Applications:
- General Purpose
- Capacitance @ Frequency:
- -
- Operating Temperature:
- -
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- DO-15
SA85CA FAQ
1.How can I place an order for SA85CA through Aetrix?
Please submit a Request for Quotation (RFQ) for SA85CA on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for SA85CA reliable?
The price and inventory of SA85CA are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SA85CA is usually 5 days.
3.What payment methods are accepted for SA85CA?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SA85CA transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SA85CA?
SA85CA orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SA85CA order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for SA85CA?
For technical support, including SA85CA datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SA85CA requirements.
6.How does Aetrix verify that SA85CA is sourced from the original manufacturer or authorized distributors?
All SA85CA products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that SA85CA meets industry standards.
7.What is the process for return or replacement of SA85CA?
All SA85CA units undergo pre-shipment inspection (PSI). If there is an issue with SA85CA, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The SA85CA part is unused and in its original packaging.
Return procedure for SA85CA:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SA85CA Tags
-
ESD9B5.0ST5G
onsemi
-
DESD3V3E1BL-7B
Diodes Incorporated
-
ESD5Z3.3T1G
onsemi
-
D5V0H1B2LP-7B
Diodes Incorporated
-
D5V0P1B2LP-7B
Diodes Incorporated
-
DESD5V0U1BA-7
Diodes Incorporated
-
ESD5Z5.0T1G
onsemi
-
DESD5V0U1BB-7
Diodes Incorporated
-
D12V0L1B2LP-7B
Diodes Incorporated
-
PESD2V0Y1BSFYL
Nexperia USA Inc.
-
DF2S5M4CT,L3F
Toshiba Semiconductor and Storage
-
D5V0L1B2WS-7
Diodes Incorporated
Tech Hub
Counterfeit components can hide behind convincing markings and passing basic function tests. This engineering reference covers source traceability, external inspection, X-ray, XRF, electrical testing, …
A practical engineering and sourcing framework covering lifecycle verification, lifetime-buy calculations, replacement qualification, supplier checks and counterfeit-risk controls.
TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
