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Microchip Technology CDLL4118
- Part No.:
- CDLL4118
- Manufacturer:
- Microchip Technology
- Category:
- Single Zener Diodes
- Package:
- DO-213AB, MELF
- Datasheet:
-
CDLL4118.pdf
- Description:
- DIODE ZENER 27V 500MW DO213AB
- Quantity:
- Payment:
- Shipping:
Inventory:9,431
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Product details
Overview
CDLL4118 from Microsemi is a hermetically sealed, surface-mount silicon Zener diode in DO-213AA (MELF/LL34) package, rated for 27 V nominal Zener voltage at 250 µA test current, with 150 Ω maximum Zener impedance, 0.01 µA maximum reverse leakage at 20.46 V, and 14 mA maximum Zener current. It operates across –65°C to +175°C junction temperature and supports precision voltage reference applications in aerospace power conditioning.
For engineers reviewing the CDLL4118 datasheet, CDLL4118 pinout, CDLL4118 application, or CDLL4118 equivalent, key selection criteria include its ±5% Zener tolerance, low-current 250 µA regulation point, hermetic glass MELF construction, thermal resistance of 100 °C/W, and suitability for high-reliability analog reference and overvoltage clamp circuits where stability under thermal stress is critical.
Technical Context
The CDLL4118 functions as a two-terminal, polarity-sensitive voltage reference device with cathode-banded orientation. Its Zener breakdown mechanism delivers stable regulation at 27 V with tight thermal coefficient behavior across –65°C to +175°C, enabled by metallurgical bonding and hermetic glass sealing.
It is specified for low-current operation (250 µA IZT), exhibits 150 Ω dynamic impedance at that bias, and maintains ≤0.01 µA reverse leakage at 20.46 V (76% of VZ). Power dissipation is rated at 500 mW at TEC = +125°C, derating linearly at 10 mW/°C above that temperature.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VZ) | 27 V nominal at 250 µA - defines precise clamping/reference level in low-power analog circuits |
| Zener Tolerance | ±5% - ensures predictable voltage margin for MIL-PRF-19500/435-compliant designs |
| Zener Impedance (ZZT) | 150 Ω max at 250 µA - limits regulation error under load transients |
| Reverse Leakage (IR) | 0.01 µA max at 20.46 V - enables ultra-low standby current in battery-backed systems |
| Max Zener Current (IZM) | 14 mA - sets upper limit for continuous power dissipation without degradation |
| Junction Temp Range | –65°C to +175°C - supports operation in extreme environments including engine bays and space-grade enclosures |
| Package | DO-213AA (MELF/LL34) - surface-mount, hermetically sealed glass case with axial COE ~6 ppm/°C |
Pinout & Package
DO-213AA (MELF/LL34) hermetically sealed glass package with axial leads; cathode identified by single dark band. No discrete pins - bidirectional two-terminal device with polarity-dependent mounting orientation.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Current entry terminal during forward bias; connected to lower potential node in Zener mode | Must be held ≤20.46 V below cathode to avoid excessive reverse leakage; not used as active signal node |
| Cathode | Current exit terminal during Zener conduction; marked with dark band | Connected to regulated voltage rail; polarity reversal causes open-circuit behavior |
Key Features
| Feature | Design Value |
|---|---|
| Hermetic glass MELF construction | Enables long-term parameter stability and moisture immunity in harsh environments per MIL-PRF-19500/435 |
| Low test current regulation (250 µA) | Reduces quiescent power draw in always-on reference circuits without sacrificing accuracy |
| Metallurgically bonded junction | Improves thermal cycling reliability and reduces parameter drift over lifetime |
| Controlled axial CTE (~6 ppm/°C) | Minimizes mechanical stress when mounted on aluminum or Kovar substrates in aerospace assemblies |
| 100 °C/W thermal resistance (RθJC) | Allows direct thermal path modeling from junction to end cap for thermal design validation |
Applications
| Aerospace Power Conditioning | High-Temperature Sensor Reference |
|---|---|
Use Scenario: Regulating reference voltage for ADCs and DACs in satellite power management units exposed to thermal vacuum cycles. IC Role / Device Role / Timing Role: Precision Zener reference providing stable 27 V bias for analog front-end circuitry. Use Value: Maintains ±5% voltage accuracy across –65°C to +175°C, enabling calibration retention without recalibration between missions. | Use Scenario: Biasing bridge sensors in turbine exhaust gas temperature monitoring systems. IC Role / Device Role / Timing Role: Low-leakage (0.01 µA) voltage clamp protecting instrumentation amplifiers from transient overvoltage. Use Value: Prevents sensor signal corruption during thermal shock events while drawing negligible standby current. |
| Avionics Overvoltage Protection | MIL-STD-704 Transient Clamping |
Use Scenario: Secondary overvoltage clamp in 28 V DC distribution panels for fighter aircraft avionics busses. IC Role / Device Role / Timing Role: Fast-response Zener element absorbing energy from load dump transients. Use Value: Withstands 14 mA peak Zener current and dissipates up to 500 mW at +125°C end-cap temperature. | Use Scenario: Compliance protection against MIL-STD-704A/B/C voltage spikes on airborne radar power inputs. IC Role / Device Role / Timing Role: Standby-mode voltage limiter activated only during >30 V transients. Use Value: 20.46 V clamping threshold (76% of VZ) ensures early activation before downstream IC damage occurs. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener reference applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| 1N4118UR-1 | Same 27 V Zener rating, ±5% tolerance, but in axial leaded DO-204AH (DO-35) package with higher RθJC (150 °C/W) | Requires through-hole PCB layout and manual soldering; unsuitable for automated SMT lines | Select when legacy board rework or hand-soldered prototypes demand axial form factor |
| BZX84-C27LT1G | 27 V Zener, ±5%, but in SOT-23 package with 200 Ω ZZT, 100 nA IR @ 20.46 V, and –65°C to +150°C rating | Limited to commercial/industrial temp range; lacks MIL-PRF-19500 qualification and hermetic sealing | Select for cost-sensitive industrial controls where extended temperature and radiation hardness are not required |
Compared with CDLL4118, 1N4118UR-1 offers identical electrical specs but requires through-hole assembly, while BZX84-C27LT1G trades hermetic reliability and extended temperature range for smaller footprint and lower cost in non-military applications.
Availability
CDLL4118 is available at Aetrix Electronics and suitable for aerospace power conditioning, high-temperature sensor reference, and avionics overvoltage protection requiring stable component supply under MIL-PRF-19500/435 compliance.
Supply support for CDLL4118 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
Microsemi (now part of Microchip Technology) is a U.S.-based semiconductor company specializing in high-reliability analog, RF, and timing solutions for defense, aerospace, and industrial markets.
The CDLL4099–CDLL4135 series was designed specifically for military-grade Zener reference and clamp applications demanding hermetic packaging, wide temperature operation, and MIL-PRF-19500/435 qualification.
FAQ
What is the Zener voltage tolerance for CDLL4118?
The CDLL4118 has a nominal Zener voltage of 27 V with a tolerance of ±5%, as specified in Note 1 of the official Microsemi datasheet. This tolerance applies when measured at 25°C ±3°C with the device junction in thermal equilibrium. The CDLL4118 does not carry a "C" (±2%) or "D" (±1%) suffix, confirming its standard ±5% grade.
Is CDLL4118 suitable for surface-mount assembly?
Yes, CDLL4118 uses the DO-213AA (MELF/LL34) package, a leadless, cylindrical surface-mount format designed for reflow soldering. Its hermetic glass body and tin/lead lead finish comply with standard SMT processes, and its axial coefficient of expansion (~6 ppm/°C) is optimized for compatibility with common PCB substrate materials.
What is the maximum power dissipation for CDLL4118 at +125°C?
The CDLL4118 is rated for 500 mW DC power dissipation at an end-cap temperature (TEC) of +125°C. Above this temperature, power must be linearly derated at 10 mW/°C - for example, at +150°C TEC, maximum allowable dissipation drops to 250 mW. This rating assumes proper thermal mounting per Microsemi's application guidance.
Does CDLL4118 meet any military specifications?
Yes, CDLL4118 is manufactured and tested per MIL-PRF-19500/435, covering Zener diodes for electronic equipment. It is qualified for JAN, JANTX, JANTXV, and JANS levels depending on screening, and its hermetic DO-213AA package, –65°C to +175°C operating range, and metallurgical construction fulfill key requirements of this specification.
What is the reverse leakage current of CDLL4118 at its rated clamping voltage?
The CDLL4118 specifies a maximum reverse leakage current of 0.01 µA at 20.46 V - which is 76% of its nominal 27 V Zener voltage. This value is measured at 25°C and reflects the device's ability to maintain ultra-low standby current in precision clamp and reference configurations where leakage-induced errors must be minimized.
CDLL4118 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Microchip Technology
- Series:
- -
- Package/Case:
- DO-213AB, MELF
- Packaging:
- Bulk
- Product Status:
- Active
- Voltage - Zener (Nom) (Vz):
- 27 V
- Tolerance:
- ±5%
- Power - Max:
- 500 mW
- Impedance (Max) (Zzt):
- 150 Ohms
- Current - Reverse Leakage @ Vr:
- 50 nA @ 20.5 V
- Voltage - Forward (Vf) (Max) @ If:
- 1.1 V @ 200 mA
- Operating Temperature:
- -55°C ~ 175°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- DO-213AB
CDLL4118 FAQ
1.How can I place an order for CDLL4118 through Aetrix?
Please submit a Request for Quotation (RFQ) for CDLL4118 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 CDLL4118 reliable?
The price and inventory of CDLL4118 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for CDLL4118 is usually 5 days.
3.What payment methods are accepted for CDLL4118?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for CDLL4118 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for CDLL4118?
CDLL4118 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your CDLL4118 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 CDLL4118?
For technical support, including CDLL4118 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your CDLL4118 requirements.
6.How does Aetrix verify that CDLL4118 is sourced from the original manufacturer or authorized distributors?
All CDLL4118 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 CDLL4118 meets industry standards.
7.What is the process for return or replacement of CDLL4118?
All CDLL4118 units undergo pre-shipment inspection (PSI). If there is an issue with CDLL4118, 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 CDLL4118 part is unused and in its original packaging.
Return procedure for CDLL4118:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
CDLL4118 Tags
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MMBZ5240B-7-F
Diodes Incorporated
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BZT52C5V6T-7
Diodes Incorporated
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MMSZ5231B-7-F
Diodes Incorporated
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BZT52C15-7-F
Diodes Incorporated
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BZX84C3V3LT1G
onsemi
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MMSZ5245BS-7-F
Diodes Incorporated
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MMSZ4682T1G
onsemi
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BZT52C15S-7-F
Diodes Incorporated
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MM5Z5V1ST1G
onsemi
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SMAJ4744A-TP
Micro Commercial Co
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BZT52C3V6LP-7
Diodes Incorporated
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SMAZ12-13-F
Diodes Incorporated
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