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Diodes Incorporated AP1688MTR-G1
- Part No.:
- AP1688MTR-G1
- Manufacturer:
- Diodes Incorporated
- Category:
- LED Drivers
- Package:
- 8-SOIC (0.154", 3.90mm Width)
- Datasheet:
-
AP1688MTR-G1.pdf
- Description:
- IC LED DRIVER OFFL 8SO
- Quantity:
- Payment:
- Shipping:
Inventory:3,413
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Product details
Overview
AP1688MTR-G1 from Diodes Incorporated is a discontinued AC/DC LED driver controller implementing boundary conduction mode (BCM) buck topology for universal mains input (85–265 VAC). It delivers constant-current regulation with ±5% accuracy, >0.9 power factor, and >90% efficiency in SO-8 package, targeting cost-sensitive indoor LED luminaires.
For engineers reviewing the AP1688MTR-G1 datasheet, AP1688MTR-G1 pinout, AP1688MTR-G1 application, or AP1688MTR-G1 equivalent, key selection criteria include BCM operation for EMI reduction, open-loop current control eliminating compensation components, and integrated protections including overvoltage, short/open-circuit, overcurrent, and overtemperature.
Technical Context
The AP1688 operates as an open-loop BCM buck controller with zero-current detection (ZCD) for valley switching, enabling high PF and low THD without feedback loop compensation. Its VA and VS pins monitor output voltage average and negative terminal respectively to support tight CC regulation across universal input.
Internal circuitry includes a 4.0 V typical CV threshold at FB, 18–20 V start-up threshold, 7–9 V minimum operating voltage, and 170°C thermal shutdown with 20°C hysteresis. The OUT pin drives external MOSFETs with 300 mA sink/source capability and 100–190 ns rise/fall times.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Topology | Buck converter with boundary conduction mode (BCM) for high PF & low EMI |
| Power Factor | >0.9 at full load, achieved via open-loop input current shaping |
| Constant Current Accuracy | ±5% over line/load/temperature, enabled by VA/VS sensing and internal reference |
| Efficiency | >90% typical at rated output, due to low ICC(OPR) (1.0–1.3 mA) and optimized gate drive |
| Start-up Threshold | 18–20 V on VCC, enabling reliable initiation from bulk capacitor charging |
| Operating Voltage Range | 12–21 V on VCC, with UVLO hysteresis supporting stable operation across temperature |
| Thermal Shutdown | 170°C junction temperature with 20°C hysteresis, preventing latch-up during overload |
Pinout & Package
AP1688MTR-G1 is housed in an SO-8 (M) package with exposed pad not electrically connected. Pin 1 is NC (no connection), simplifying PCB layout by eliminating routing constraints at that location.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 NC | No connection | Unused pin; must remain unconnected per datasheet to avoid malfunction |
| 2 VS | Output negative terminal sense | Detects VOUT- for open-load detection and current regulation stability |
| 3 VA | Average output negative voltage sense | Provides averaged feedback for precise constant-current setpoint under varying loads |
| 4 CS | Primary-side current sense | Monitors MOSFET source current for peak current limiting and ZCD timing |
| 5 FB | Auxiliary winding feedback | Senses reflected voltage to regulate output current via 4.0 V CV threshold |
| 6 GND | Signal and power ground | Common return path for control logic, sensing, and gate drive return |
| 7 OUT | High-current gate driver output | Drives external N-channel MOSFET with 300 mA sink/source and fast edge rates |
| 8 VCC | IC supply input | Accepts 12–21 V bias; powers internal regulator, logic, and gate driver circuits |
Key Features
| Feature | Design Value |
|---|---|
| BCM operation | Enables >0.9 PF and simplified EMI filter design without complex control loop tuning |
| Open-loop current control | Eliminates external compensation network, reducing BOM count and layout sensitivity |
| Integrated protection suite | Includes OVP (FB > 4.5 V), SCP (CS > 4 V), OTP (170°C), and open/reload detection |
| Low start-up current | ≤20 µA enables use of high-value start-up resistors, improving system reliability |
| Green RoHS/Green package | Lead-free, halogen-free, and antimony-free per Diodes' definition (<900 ppm Br/Cl, <1000 ppm Sb) |
Applications
| Indoor LED Downlights | LED Panel Lights |
|---|---|
Use Scenario: 12–24 W retrofit downlight operating directly from 120/230 VAC mains with passive cooling. IC Role / Device Role / Timing Role: BCM buck controller regulating LED string current without secondary-side feedback. Use Value: Achieves >90% efficiency and >0.9 PF while eliminating optocoupler and TL431, lowering system cost. | Use Scenario: Flat-panel LED lighting for office ceilings requiring uniform brightness and low THD. IC Role / Device Role / Timing Role: Primary-side constant-current controller using VA/VS sensing for accurate current regulation. Use Value: ±5% current accuracy ensures consistent lumen output across input voltage variation (85–265 VAC). |
| LED Troffer Lights | LED Streetlight Drivers (Low-Power) |
Use Scenario: 30–40 W troffer fixture with aluminum heat sink and wide ambient range (-40°C to +105°C). IC Role / Device Role / Timing Role: High-reliability buck controller with thermal shutdown and overvoltage protection. Use Value: 170°C OTP with 20°C hysteresis prevents thermal runaway during sustained overload or poor heatsinking. | Use Scenario: 20–30 W outdoor streetlight driver with surge immunity and long-life requirements. IC Role / Device Role / Timing Role: Universal-input LED driver IC with open-circuit and short-circuit protection. Use Value: Integrated open/short detection avoids false triggering during lamp aging or cold-start conditions. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar LED driver controller applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| AL1665 | Successor part with enhanced ESD rating (4 kV HBM), lower start-up current (15 µA), and extended VCC OVP (38 V) | Same SO-8 footprint and pinout; supports higher input surges and faster startup | Select AL1665 for new designs requiring longer lifecycle support and improved robustness |
| BP5771E | Single-stage flyback controller with integrated 650 V MOSFET; no external switch required | Higher integration reduces component count but limits max output power to ~15 W | Choose BP5771E only for compact, low-power (<15 W) designs where board space is critical |
Compared with AP1688MTR-G1, AL1665 offers direct replacement compatibility and improved surge tolerance, while BP5771E trades external MOSFET flexibility for integration-making AL1665 the preferred upgrade path for existing AP1688-based platforms.
Availability
AP1688MTR-G1 is available at Aetrix Electronics and suitable for indoor LED downlights, panel lights, and troffer fixtures requiring stable component supply despite its obsolete status.
Supply support for AP1688MTR-G1 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
Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, headquartered in Plano, Texas, with design, manufacturing, and sales operations across Asia, Europe, and the Americas.
The AP1688 belongs to Diodes' LED lighting controller product line, engineered specifically for cost-effective, high-PF, primary-side regulated AC/DC LED drivers targeting residential and commercial lighting markets.
FAQ
Is AP1688MTR-G1 still recommended for new designs?
No. Diodes Incorporated has officially discontinued the AP1688 and recommends AL1665 as its direct successor. While AP1688MTR-G1 remains available through authorized channels for legacy production, new designs should adopt AL1665 to ensure long-term supply, enhanced ESD performance (4 kV HBM), and updated safety features.
What is the function of the NC pin (Pin 1) on AP1688MTR-G1?
Pin 1 is a no-connect terminal with no internal connection. It must remain unconnected on the PCB per the datasheet; routing or soldering to this pin may disrupt internal biasing or cause unpredictable behavior. This design choice simplifies layout and eliminates potential noise coupling paths.
How does AP1688 achieve constant-current regulation without secondary-side feedback?
The AP1688 uses primary-side sensing via VA and VS pins to reconstruct output current from auxiliary winding voltage and MOSFET conduction time. Combined with fixed CV threshold (4.0 V) at FB and open-loop BCM timing, it maintains ±5% current accuracy across line/load without optocouplers or secondary controllers.
Can AP1688MTR-G1 be used in automotive LED lighting applications?
No. AP1688MTR-G1 is not qualified to AEC-Q100 or IATF 16949 standards and lacks automotive-grade screening, temperature range extension beyond +105°C, or PPAP documentation. Diodes explicitly states that automotive use requires contacting their representative for qualified alternatives such as the AL8862Q or AL1697Q series.
AP1688MTR-G1 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Diodes Incorporated
- Series:
- -
- Package/Case:
- 8-SOIC (0.154", 3.90mm Width)
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Type:
- AC DC Offline Switcher
- Topology:
- Step-Down (Buck)
- Internal Switch(s):
- No
- Number of Outputs:
- 1
- Voltage - Supply (Min):
- 12V
- Voltage - Supply (Max):
- 21V
- Voltage - Output:
- -
- Current - Output / Channel:
- -
- Frequency:
- -
- Dimming:
- -
- Applications:
- Lighting
- Operating Temperature:
- -40°C ~ 105°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 8-SO
AP1688MTR-G1 FAQ
1.How can I place an order for AP1688MTR-G1 through Aetrix?
Please submit a Request for Quotation (RFQ) for AP1688MTR-G1 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 AP1688MTR-G1 reliable?
The price and inventory of AP1688MTR-G1 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for AP1688MTR-G1 is usually 5 days.
3.What payment methods are accepted for AP1688MTR-G1?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for AP1688MTR-G1 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for AP1688MTR-G1?
AP1688MTR-G1 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your AP1688MTR-G1 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 AP1688MTR-G1?
For technical support, including AP1688MTR-G1 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your AP1688MTR-G1 requirements.
6.How does Aetrix verify that AP1688MTR-G1 is sourced from the original manufacturer or authorized distributors?
All AP1688MTR-G1 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 AP1688MTR-G1 meets industry standards.
7.What is the process for return or replacement of AP1688MTR-G1?
All AP1688MTR-G1 units undergo pre-shipment inspection (PSI). If there is an issue with AP1688MTR-G1, 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 AP1688MTR-G1 part is unused and in its original packaging.
Return procedure for AP1688MTR-G1:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
AP1688MTR-G1 Tags
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BCR402RE6327HTSA1
Infineon Technologies
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BCR430UXTSA2
Infineon Technologies
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BCR420UE6433HTMA1
Infineon Technologies
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BCR420UE6327HTSA1
Infineon Technologies
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BCR421UE6327HTSA1
Infineon Technologies
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LYT1604D-TL
Power Integrations
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HV9910CLG-G
Microchip Technology
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CL2N8-G
Microchip Technology
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BCR420UW6-7
Diodes Incorporated
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BCR421UW6-7
Diodes Incorporated
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BCR420UFD-7
Diodes Incorporated
-
BCR421UFD-7
Diodes Incorporated
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