My Inquiry
My Account
Nexperia USA Inc. BAS21THR
- Part No.:
- BAS21THR
- Manufacturer:
- Nexperia USA Inc.
- Category:
- Single Diodes
- Package:
- TO-236-3, SC-59, SOT-23-3
- Datasheet:
-
BAS21THR.pdf
- Description:
- DIODE GP 200V 200MA TO236AB
- Quantity:
- Payment:
- Shipping:
Inventory:664
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
BAS21THR from Nexperia is a high-voltage switching diode in SOT23 package, rated for 250 V repetitive peak reverse voltage (VRRM), 200 mA forward current (IF), and 50 ns reverse recovery time (trr). It operates up to 175 °C junction temperature and serves as a fast, thermally robust switching element in DC-DC converter flyback snubbers and high-side clamp circuits.
For engineers reviewing the BAS21THR datasheet, BAS21THR pinout, BAS21THR application, or BAS21THR equivalent, key selection criteria include its 250 V VRRM rating, 50 ns trr at 30 mA, 1.25 V VF at 200 mA, 100 nA IR at 200 V, and SOT23 thermal resistance of 500 K/W on FR4 PCB - all critical for high-voltage transient suppression and high-frequency switching integrity.
Technical Context
The BAS21THR is a planar epitaxial silicon switching diode optimized for high-voltage, medium-speed operation. Its 250 V VRRM and 200 V VR ratings support use in 200 V-class power rails, while its 50 ns trr enables reliable operation up to ~10 MHz switching frequencies in clamping and snubbing topologies.
Thermal design is enabled by its 175 °C maximum junction temperature and defined Rth(j-a) = 500 K/W on standard FR4 PCB. The device's 5 pF capacitance at 0 V and low leakage (100 nA @ 200 V, 25 °C) ensure minimal signal coupling and standby power loss in high-impedance bias networks.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VRRM | 250 V - supports continuous reverse blocking in 200 V DC bus applications with 25 % safety margin |
| trr | 50 ns - enables clean turn-off in 1–10 MHz switching converters without excessive switching loss or ringing |
| VF @ 200 mA | 1.25 V - limits conduction loss to ≤250 mW in series-switching paths at rated current |
| IR @ 200 V | 100 nA - ensures negligible leakage current in high-impedance voltage divider or bias networks |
| Tj max | 175 °C - allows operation in under-hood automotive modules and industrial motor drive control boards |
| Cd @ 0 V | 5 pF - minimizes capacitive loading on high-speed logic or RF detector nodes |
Pinout & Package
Encapsulated in a standard SOT23 (TO-236AB) plastic surface-mount package measuring 2.9 mm × 1.3 mm × 1.0 mm with 1.9 mm lead pitch and tin-plated terminations.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Anode (A) | Forward current entry point; connects to higher-potential node in switching path |
| 2 | Not Connected (n.c.) | Internally isolated; must remain unconnected on PCB to avoid parasitic coupling or thermal stress |
| 3 | Cathode (K) | Forward current exit and reverse voltage reference terminal; ties to ground or low-side switch node |
Key Features
| Feature | Design Value |
|---|---|
| High-voltage blocking | 250 V VRRM enables use in 170–200 V AC rectified or PoE-powered systems without derating |
| Fast recovery | 50 ns trr reduces reverse recovery charge (Qrr) to <15 nC, minimizing EMI in flyback snubbers |
| High-temperature capability | 175 °C Tj max supports placement near MOSFETs or transformers in compact power modules |
| Low-leakage performance | 100 nA IR at 200 V ensures stable biasing in precision voltage references and sensor front-ends |
Applications
| Switch-Mode Power Supply Snubber | High-Voltage Clamp Circuit |
|---|---|
Use Scenario: Placed across transformer primary winding in offline flyback converters to suppress voltage spikes during MOSFET turn-off. IC Role / Device Role / Timing Role: Fast-recovery diode providing low-loss, low-capacitance path for stored inductive energy dissipation. Use Value: 50 ns trr and 250 V VRRM prevent secondary breakdown while limiting overshoot to <5 % above nominal rail. |
Use Scenario: Used in overvoltage protection circuits for 100–200 V DC rails in industrial PLC I/O modules. IC Role / Device Role / Timing Role: High-voltage clamping diode shunting transients to ground when rail exceeds safe threshold. Use Value: 100 nA IR at 200 V ensures no measurable drift in reference voltage dividers feeding comparator inputs. |
| Automotive Body Control Module | Industrial Sensor Signal Conditioning |
Use Scenario: Integrated into load-dump protection networks for 12 V/24 V automotive subsystems operating up to 175 °C ambient. IC Role / Device Role / Timing Role: High-temperature-rated switching diode absorbing ISO 7637-2 pulse 5a/b energy surges. Use Value: 175 °C Tj rating and 500 K/W Rth(j-a) allow direct mounting on hot-control board sections without heatsinking. |
Use Scenario: Employed in precision bridge rectifier stages for RTD or thermocouple signal conditioning in factory-floor sensors. IC Role / Device Role / Timing Role: Low-capacitance (5 pF), low-leakage diode enabling accurate microamp-level current steering. Use Value: 5 pF Cd minimizes phase shift in 10 kHz–100 kHz excitation signals; 100 nA IR avoids offset errors in µV-range measurements. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar high-voltage switching diode applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| ON Semiconductor MMBD2103LT1G | VRRM = 200 V (50 V lower); trr = 50 ns; VF = 1.25 V @ 200 mA; same SOT23 package | Not suitable for 200 V+ DC bus clamping; acceptable only in ≤170 V systems | Select only if system VRMS × √2 + margin stays below 200 V |
| Diodes Incorporated BAV21W-7-F | VRRM = 250 V; trr = 50 ns; VF = 1.25 V @ 200 mA; but Tj max = 150 °C (25 °C lower) | Limited to 150 °C ambient environments; unsuitable for under-hood or enclosed power modules | Prefer for cost-sensitive consumer designs where thermal headroom ≥25 °C exists |
Compared with MMBD2103LT1G and BAV21W-7-F, BAS21THR uniquely combines 250 V VRRM, 50 ns trr, and 175 °C Tj in one SOT23 device - making it the only option among the three qualified for high-reliability 200 V-class industrial and automotive-adjacent applications requiring extended thermal margin.
Availability
BAS21THR is available at Aetrix Electronics and suitable for high-voltage snubbers, DC-DC clamp circuits, automotive body control modules, and industrial sensor signal conditioning requiring stable component supply across extended temperature ranges.
Supply support for BAS21THR 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 headquartered in Nijmegen, Netherlands, specializing in high-performance, high-reliability discrete and logic devices for automotive, industrial, and computing markets.
The BAS21THR belongs to Nexperia's high-voltage switching diode product line, engineered specifically for fast, thermally resilient clamping and snubbing in power conversion and surge protection circuits operating up to 175 °C.
FAQ
Is BAS21THR automotive-qualified?
No. Per Nexperia's revision history (v.3, Sept 2025), BAS21THR is explicitly non-automotive qualified. It lacks AEC-Q101 certification and has not undergone automotive-grade qualification testing. For automotive use, Nexperia recommends its -Q qualified variants such as BAS21TH-Q, which undergo full AEC-Q101 stress testing and PPAP documentation.
What is the maximum continuous forward current for BAS21THR?
The maximum continuous forward current (IF) is 200 mA at Tamb ≤ 25 °C on standard FR4 PCB with single-side copper. At 100 °C ambient, derating reduces usable IF to approximately 120 mA based on the 300 mW Ptot limit and 500 K/W Rth(j-a) - confirmed by Figure 1's power derating curve in the datasheet.
Can BAS21THR replace BAS21 in existing designs?
Yes, with verification. BAS21THR shares identical pinout, electrical specs (VRRM, trr, VF), and SOT23 package with legacy BAS21, but adds enhanced thermal capability (Tj max = 175 °C vs. 150 °C) and updated non-automotive qualification status. Layout and schematic compatibility is maintained, though thermal margin improves significantly.
How does the n.c. pin affect PCB layout?
Pin 2 is internally not connected and must remain unconnected on the PCB. Routing traces to or placing solder paste on this pad risks mechanical stress, thermal imbalance, or unintended coupling. The official footprint (Figure 10) shows no solder land for Pin 2 - only Pins 1 and 3 require copper pads per Nexperia's reflow guidelines.
BAS21THR Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Nexperia USA Inc.
- Series:
- BAS16
- Package/Case:
- TO-236-3, SC-59, SOT-23-3
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Technology:
- Standard
- Voltage - DC Reverse (Vr) (Max):
- 200 V
- Current - Average Rectified (Io):
- 200mA
- Voltage - Forward (Vf) (Max) @ If:
- 1.25 V @ 200 mA
- Speed:
- Small Signal =< 200mA (Io), Any Speed
- Reverse Recovery Time (trr):
- 50 ns
- Current - Reverse Leakage @ Vr:
- 100 nA @ 200 V
- Capacitance @ Vr, F:
- 5pF @ 0V, 1MHz
- Grade:
- Automotive
- Qualification:
- AEC-Q101
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- TO-236AB
- Operating Temperature - Junction:
- 175°C (Max)
BAS21THR FAQ
1.How can I place an order for BAS21THR through Aetrix?
Please submit a Request for Quotation (RFQ) for BAS21THR 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 BAS21THR reliable?
The price and inventory of BAS21THR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BAS21THR is usually 5 days.
3.What payment methods are accepted for BAS21THR?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BAS21THR transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BAS21THR?
BAS21THR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BAS21THR 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 BAS21THR?
For technical support, including BAS21THR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BAS21THR requirements.
6.How does Aetrix verify that BAS21THR is sourced from the original manufacturer or authorized distributors?
All BAS21THR 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 BAS21THR meets industry standards.
7.What is the process for return or replacement of BAS21THR?
All BAS21THR units undergo pre-shipment inspection (PSI). If there is an issue with BAS21THR, 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 BAS21THR part is unused and in its original packaging.
Return procedure for BAS21THR:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BAS21THR Tags
-
1N4448X-TP
Micro Commercial Co
-
1N4148WX-TP
Micro Commercial Co
-
1N4148TR
onsemi
-
MMSD4148T1G
onsemi
-
MMBD914LT3G
onsemi
-
BAS16HT1G
onsemi
-
1N914BWT
onsemi
-
BAS21LT1G
onsemi
-
LL4148
onsemi
-
BAS16LT1G
onsemi
-
MMSD914T1G
onsemi
-
BAV21W-7-F
Diodes Incorporated
Tech Hub
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…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
