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Nexperia USA Inc. BZX585-B12,135
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- Part No.:
- BZX585-B12,135
- Manufacturer:
- Nexperia USA Inc.
- Category:
- Single Zener Diodes
- Package:
- SC-79, SOD-523
- Datasheet:
-
BZX585-B12,135.pdf
- Description:
- DIODE ZENER 12V 300MW SOD523
- Quantity:
- Payment:
- Shipping:
Inventory:8,125
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Product details
Overview
BZX585-B12,135 from Nexperia is a 12 V ±2 % Zener voltage regulator diode in an SOD523 (SC-79) ultra-small surface-mount package, rated for 300 mW total power dissipation and 40 W non-repetitive peak reverse power, used for precision low-power voltage reference and overvoltage protection in space-constrained consumer and industrial power rails.
For engineers reviewing the BZX585-B12,135 datasheet, BZX585-B12,135 pinout, BZX585-B12,135 application, or BZX585-B12,135 equivalent, this part supports stable 12 V regulation at 5 mA test current with 25 Ω typical differential resistance, low 0.1 µA reverse leakage at 9.6 V, and thermal resistance of 65 K/W to solder point - critical for compact DC-DC feedback networks and ESD-clamped I/O protection.
Technical Context
This Zener diode operates in reverse breakdown mode with a nominal 12 V Zener voltage (VZ) at IZ = 5 mA, exhibiting a temperature coefficient of +6.0 mV/K and differential resistance of 25 Ω (typ) at that bias. Its SC-79 package enables high-density placement while maintaining thermal performance via low Rth(j-sp) = 65 K/W.
The device sustains non-repetitive surge pulses up to 40 W (tp = 100 µs, square wave), with forward voltage ≤1.1 V at 100 mA and junction temperature range from −65 °C to +150 °C - enabling robust operation in transient-prone 12 V supply monitoring and clamping circuits.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VZ) | 11.76 V to 12.24 V at IZ = 5 mA - ensures tight 12 V regulation tolerance for feedback loop stability in low-noise LDOs. |
| Differential Resistance (rdiff) | 25 Ω (typ) at IZ = 5 mA - minimizes output voltage shift under load variation in reference applications. |
| Reverse Current (IR) | ≤ 0.1 µA at VR = 9.6 V - guarantees negligible quiescent current draw in battery-powered standby circuits. |
| Total Power Dissipation (Ptot) | 300 mW at Tamb = 25 °C on FR4 PCB with 35 mm² copper - defines maximum continuous DC power handling in compact layouts. |
| Non-repetitive Peak Power (PZSM) | 40 W for tp = 100 µs - supports transient suppression of short-duration surges without degradation. |
| Thermal Resistance (Rth(j-sp)) | 65 K/W to solder point - enables direct thermal coupling to PCB copper for reliable operation in thermally dense designs. |
| Forward Voltage (VF) | ≤ 1.1 V at IF = 100 mA - allows use as low-drop rectifier or polarity protection element in dual-role circuits. |
Pinout & Package
Package: SOD523 (SC-79), ultra-small flat-lead surface-mount plastic package with cathode band marking; dimensions: 1.25 mm × 0.85 mm × 0.65 mm (L × W × H), 2-terminal configuration.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (marked side) | Cathode (K) | Connected to regulated output node; reverse-biased terminal where Zener breakdown occurs at 12 V. |
| 2 | Anode (A) | Connected to ground or lower-potential rail; completes reverse-bias path for regulation and clamping functions. |
Key Features
| Feature | Design Value |
|---|---|
| ±2 % Zener voltage tolerance | Enables precise 12 V reference without external trimming in analog sensor biasing and ADC reference circuits. |
| Low 25 Ω differential resistance | Reduces output impedance by >4× vs. ±5 % variants, improving line regulation in feedback divider networks. |
| 40 W non-repetitive surge rating | Withstands IEC 61000-4-5 Level 3 surges without parameter shift when placed at board-level input protection points. |
| 0.1 µA max reverse leakage at 9.6 V | Minimizes standby current in always-on 12 V monitoring circuits, extending battery life in portable instrumentation. |
| Rth(j-sp) = 65 K/W | Permits direct thermal anchoring to PCB copper pour, avoiding derating below 250 mW in 10 mm² thermal pads. |
Applications
| Power Supply Feedback Reference | Overvoltage Clamp for 12 V Rail |
|---|---|
|
Use Scenario: Stabilizing output voltage of a 12 V switching regulator via resistor divider into error amplifier. IC Role / Device Role: Provides accurate 12 V Zener reference to set feedback threshold; replaces bulkier TO-92 or SOT-23 alternatives. Use Value: Tight ±2 % tolerance and 25 Ω rdiff reduce output drift to <±15 mV across load and temperature, meeting Class II industrial PSU specs. |
Use Scenario: Protecting microcontroller I/O pins connected to a 12 V automotive accessory line subject to load dump transients. IC Role / Device Role: Clamps voltage spikes above 12.24 V to safe levels before reaching sensitive CMOS inputs. Use Value: 40 W surge capability absorbs 100 µs transients without degradation, while 0.1 µA leakage avoids signal distortion during normal operation. |
| Low-Power Sensor Biasing | ESD-Suppressed Signal Line Protection |
|
Use Scenario: Generating stable 12 V bias for analog front-end op-amps in battery-powered environmental sensors. IC Role / Device Role: Acts as shunt regulator supplying clean bias voltage; operates continuously at 100 µA quiescent current. Use Value: Sub-µA reverse leakage preserves battery runtime over multi-year deployments, while SOD523 footprint saves >60 % board area vs. SOT-23. |
Use Scenario: Adding secondary clamping on RS-485 bus lines alongside TVS diodes to suppress residual overshoot after primary ESD event. IC Role / Device Role: Low-capacitance (≤10 pF) Zener provides fine-grained voltage limiting at 12 V common-mode level. Use Value: 10 pF capacitance avoids signal integrity loss at 250 kbps, while ±2 % tolerance ensures clamping occurs precisely within receiver common-mode range. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BZX585-C12,135 | ±5 % tolerance (11.4–12.6 V), higher 100 Ω rdiff, same package and PZSM | Acceptable for non-critical biasing where 12 V accuracy <±5 % suffices | Select for cost-sensitive designs where tighter regulation is unnecessary and leakage <0.5 µA is acceptable. |
| MMSZ5242B-7-F | 12 V ±5 %, SOD-123 package (2.7 × 1.4 mm), 500 mW Ptot, 30 Ω rdiff | Higher power handling but 3.5× larger footprint; less suitable for ultra-dense layouts | Choose when thermal margin >300 mW is required and board space permits larger SOD-123 placement. |
Compared with BZX585-C12,135, the BZX585-B12,135 delivers 2× tighter voltage control and 4× lower dynamic impedance for precision references; versus MMSZ5242B-7-F, it trades 170 mW lower power rating for 55 % smaller footprint and superior thermal coupling in space-constrained modules.
Availability
BZX585-B12,135 is available at Aetrix Electronics and suitable for power supply feedback networks, overvoltage clamp circuits, low-power sensor biasing, and ESD-suppressed signal line protection requiring stable component supply and consistent parametric performance across production lots.
Supply support for BZX585-B12,135 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
Nexperia is a global semiconductor expert delivering high-performance, reliable discrete, logic, and MOSFET devices optimized for efficiency, miniaturization, and robustness in high-volume electronics.
The BZX585 series belongs to Nexperia's general-purpose Zener diode product line, engineered specifically for space-constrained voltage regulation and clamping in consumer, industrial, and computing applications where ultra-small SMD packages and tight tolerances are essential.
FAQ
What is the maximum continuous reverse current the BZX585-B12,135 can sustain at 25 °C ambient?
The BZX585-B12,135 has a maximum continuous forward current of 200 mA, but its Zener operation relies on reverse bias. At 25 °C ambient on an FR4 PCB with 35 mm² copper, it sustains up to 25 mA continuous reverse current (derived from Ptot = 300 mW ÷ VZ ≈ 25 mA), well within its 5 mA typical test condition for specification compliance.
Does the cathode band on the SOD523 package align with Pin 1 per JEDEC standard?
Yes - the cathode band on the BZX585-B12,135 matches Pin 1 as defined in the SOD523 package outline (Figure 11). The marking bar is located adjacent to the cathode terminal, and the device orientation follows standard SC-79 pinning: cathode (K) at the banded end, anode (A) at the opposite end.
Can this Zener diode be used in place of a 12 V TVS for ESD protection?
No - while the BZX585-B12,135 clamps above 12.24 V and handles 40 W surges, it is not rated for IEC 61000-4-2 ESD events. Its 100 ns response time and lack of specified clamping voltage at 30 A make it unsuitable as primary ESD protection; it serves best as secondary clamping or precision regulation alongside dedicated TVS devices.
How does the temperature coefficient affect regulation accuracy over −40 °C to +85 °C ambient?
With a specified +6.0 mV/K temperature coefficient, the BZX585-B12,135 exhibits a +150 mV shift in VZ over a 25 °C to 125 °C junction range. At −40 °C to +85 °C ambient (assuming ΔTj-a ≈ 40 K), VZ shifts by ~240 mV - meaning regulation stays within 11.9 V to 12.4 V, remaining within ±2.5 % of nominal for most non-precision applications.
BZX585-B12,135 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Nexperia USA Inc.
- Series:
- -
- Package/Case:
- SC-79, SOD-523
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Voltage - Zener (Nom) (Vz):
- 12 V
- Tolerance:
- ±2%
- Power - Max:
- 300 mW
- Impedance (Max) (Zzt):
- 10 Ohms
- Current - Reverse Leakage @ Vr:
- 100 nA @ 8 V
- Voltage - Forward (Vf) (Max) @ If:
- 1.1 V @ 100 mA
- Operating Temperature:
- -65°C ~ 150°C
- Grade:
- Automotive
- Qualification:
- AEC-Q101
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOD-523
BZX585-B12,135 FAQ
1.How can I place an order for BZX585-B12,135 through Aetrix?
Please submit a Request for Quotation (RFQ) for BZX585-B12,135 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 BZX585-B12,135 reliable?
The price and inventory of BZX585-B12,135 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BZX585-B12,135 is usually 5 days.
3.What payment methods are accepted for BZX585-B12,135?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BZX585-B12,135 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BZX585-B12,135?
BZX585-B12,135 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BZX585-B12,135 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 BZX585-B12,135?
For technical support, including BZX585-B12,135 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BZX585-B12,135 requirements.
6.How does Aetrix verify that BZX585-B12,135 is sourced from the original manufacturer or authorized distributors?
All BZX585-B12,135 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 BZX585-B12,135 meets industry standards.
7.What is the process for return or replacement of BZX585-B12,135?
All BZX585-B12,135 units undergo pre-shipment inspection (PSI). If there is an issue with BZX585-B12,135, 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 BZX585-B12,135 part is unused and in its original packaging.
Return procedure for BZX585-B12,135:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BZX585-B12,135 Tags
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