hfbr

+## Info

+

+[product url - RS422-TTL Module, Full Duplex, RS-422](https://www.electrodragon.com/product/rs422-ttl-module-full-duplex-rs-422/)

+

+## Board Map, Dimension, Pins, etc.

+

+### Pin definition

+### Working Principle

+## Applications, category, tags, etc.

+

+## Demo Code and Video

+## old versions

+The ZYBA hole locations are in a different position AND the order has changed to YZBA.

+

+

+## ref

+- [legacy wiki page ](https://www.electrodragon.com/w/Category:Interface)

+- [RS-422](https://w.electrodragon.com/w/RS-422)

+

+- [[DPR1097]]

+

+# MAX3490-dat

+

+## Choosing Between MAX490 and MAX3490 for 3.3V Systems

+

+### ✅ Use Case: 3.3V Power Supply

+

+If your system uses a **3.3V power supply**, the **MAX3490** is the appropriate choice.

+

+### 🔍 Comparison Table

+

+| Feature | MAX490 | MAX3490 |

+|----------------|---------------------|----------------------|

+| Supply Voltage | 5V (±10%) | 3.3V (±10%) |

+| I/O Levels | TTL/CMOS (5V logic) | 3.3V CMOS compatible |

+| RS Standard | RS-485/RS-422 | RS-485/RS-422 |

+| ESD Protection | Basic | Enhanced |

+| Application | 5V Systems | 3.3V Systems |

+

+### ✅ Recommendation

+

+For 3.3V systems, use the **MAX3490**:

+- Fully compatible with 3.3V logic levels

+- Drop-in solution for RS-485/RS-422 communication

+- Low-power and ESD-protected

+

+# MAX490-dat

+

+## Power Supply

+- **Vcc (Operating Voltage):** +5V ±10% (Range: 4.5V to 5.5V)

+

+## Logic Input

+- Compatible with **TTL/CMOS logic levels** at 5V supply

+

+## Receiver Input Voltage Range

+- **Common-mode voltage range:** -7V to +12V

+

+- [[DPR1097-dat]] - [[MAX490-dat]]

+

+# SPDIF-dat

+

+https://en.wikipedia.org/wiki/S/PDIF

+

+

+

+

+## 🧪 SPDIF to TTL Interface Circuit (Basic Example)

+

+This circuit converts a **coaxial SPDIF signal** into a **5V TTL-compatible digital signal** using basic analog components.

+

+```text

+ +5V

+ │

+ [10kΩ] R1

+ │

+SPDIF ▶──C1───┬────┬───► To Comparator Input (Vin+)

+(Coaxial) │ [10kΩ] R2

+ (0.1µF) │

+ GND

+

+Comparator:

+- Vin+ → From voltage divider (above)

+- Vin− → Reference voltage (e.g. 2.5V from voltage divider or regulator)

+- Vout → 5V TTL output signal (to MCU / logic circuit)

+```

+

+### 🧰 Components:

+- `C1`: 0.1 µF ceramic capacitor (AC coupling)

+- `R1`, `R2`: 10kΩ resistors to create a bias voltage (~2.5V)

+- **Comparator**: e.g. LMV7219, TLV3501 (fast response)

+- Optional: Schmitt trigger buffer (e.g. 74HC14) for clean signal output

+

+### ⚠️ Notes:

+- Always AC-couple SPDIF input to protect from DC offsets.

+- Adjust resistor values for different bias points if needed.

+- For more reliable decoding, consider using a dedicated SPDIF receiver chip like `DIR9001` or `CS8416`.

+

+### matched connectors

+

+

+

+[[TOSLINK-dat]] [[SPDIF-dat]] connector - [[interface-dat]]

+

+[reference](https://wiki.odroid.com/odroid-c2/application_note/external_connector/spdif)

+

+

+## Everlight PLT131/T1/12 Photolink Fiber Optic Transmitter 650nm

+## PLR135/T8

+

+

+

+

+

+

+

+

+project [SPDIF to TOSLink Adapter Hat for Quartz64](https://github.com/CounterPillow/quartz64-toslink-hat)

+

+

+## DLR 1121

+

+

+## DLR 2180

+

+

+

+

+

+

+

+

+

+[toslink-guide](https://www.tme.eu/Document/3363e65f4c705941469014401686faf2/TOFC100-xx.pdf)

+

+

+## TOTX178A

+

+- [[totx178.pdf]]

+

+

+

+

+## Optical SPDIF (TOSLINK):

+

+- Uses optical fiber (plastic or glass).

+- Has a TOSLINK connector (square-ish plug).

+- Carries light-based digital signals.

+- Immune to electrical interference (a bonus in noisy environments).

+

+## Why Not Use TOSLINK for Transferring 5V TTL Serial Signals?

+

+While **TOSLINK** (optical) is a popular and widely used optical standard, especially for **consumer audio** (like SPDIF), it's **not ideally suited** for directly transferring TTL serial signals like 5V logic. Here's why **POF** (Plastic Optical Fiber) is often a better choice for serial TTL communication over **TOSLINK**:

+

+### 🔍 Key Differences:

+

+#### 1. Signal Type:

+- **TOSLINK (SPDIF)** carries **digital audio** data, which is encoded in a **biphase-mark** format (a specific way of encoding 1s and 0s for audio).

+ - It's not **raw TTL**, so you'd need a **decoder** or **receiver chip** to convert it back into useful serial data.

+ - It's designed for **audio signals**, not serial communication.

+- **POF (Plastic Optical Fiber)** with **TTL transceivers** is specifically designed to carry **digital data signals** such as serial UART, which is just **raw bits** (high and low voltages) transmitted directly over light.

+

+#### 2. Electrical Compatibility:

+- **TOSLINK** optical transmitters and receivers are **designed for audio** signals that operate at relatively lower frequencies (44.1kHz or 48kHz for audio sampling).

+ - **TTL signals**, on the other hand, are **high-speed** and require a continuous **stream of binary data** (e.g., 115200 baud rate or higher) without the need for extra encoding schemes.

+- **POF with TTL transceivers** directly handles **5V logic signals**, making it simpler and **more compatible** with serial communication.

+

+# DLR2180-dat

+

+

+DLR28012

+https://www.edison-opto.com/_i/assets/file/productlist/8DLR28000000000A.pdf

+

+- [[DLR2180-datasheet.pdf]]

+

+

+## DLT1111A

+

+http://www.hy1688.com.tw/SWITCH/DC%20JACK%20HOME/Optical_File/DLT1111A.pdf

+

+# HFBR-0500Z-Series-dat

+

+Internal optics have been optimized for use with 1-mm diameter polymer optical fiber. Versatile Link specifications incorporate all connector interface losses. Therefore, optical calculations for common link applications are simplified.

+

+[HFBR-0500Z Series Versatile Link Fiber-Optic Connection](https://docs.broadcom.com/doc/AV02-1501EN)

+

+

+Yes, you can insert a bare end POF cable into the Broadcom HFBR-0500 Series transceivers (e.g., HFBR-1521Z, HFBR-2521Z, etc.) — that’s one of their key advantages.

+

+✅ Here's how it works:

+

+The HFBR-0500 series is designed for tool-less, field-installable connections.

+

+You can directly cut and insert a 1 mm core POF cable (typically with 2.2 mm jacket) into the transceiver.

+

+No pre-attached connector is required.

+

+https://www.broadcom.com/products/fiber-optic-modules-components/industrial/industrial-control-general-purpose/650nm/hfbr-1521z

+

+# HFBR-dat

+

+HFBR-4503Z

+

+- [[HFBR-0500Z-Series-dat]]

+

+- [[HFBR]] - [[POF]]

+

+## Best Way to Use POF for 5V TTL Serial:

+

+ TX Side (Microcontroller)

+ --------------------------

+ MCU TX ──► HFBR-1521 (Transmitter)

+ GND ─────┬──────────────────────┐

+ Vcc (5V) ──────────────────────►

+

+ RX Side (Receiver)

+ -------------------

+ POF Fiber ──► HFBR-2521 (Receiver)

+ Output ─────► MCU RX

+ GND ─────────┴──────────────────

+

+

+## ref

+

+- [[TOSlink-dat]]

+- [[FC300T-dat]] - [[Photolink-dat]] - [[HFBR-0500Z-Series-dat]]

+- [[DLR2180-dat]] - [[TCPT1200-dat]] - [[vishay-dat]]

+

+- [[toshiba-dat]] - [[TOTX-TORX-dat]] - [[toslink-dat]]

+

+# LC-connector-dat.md

+

+## LC module

+

+LC stands for Lucent Connector.

+

+LC connectors are smaller versions of SC connectors, commonly used in high-density fiber optic applications.

+

+### Features:

+

+Small form factor: Half the size of SC connectors, making them ideal for space-limited environments like data centers.

+

+Latch mechanism: Uses a clip-on design for easy and secure connection.

+

+High-density applications: Commonly used in network switches, routers, and patch panels.

+

+Fiber types: Can be used with both single-mode and multi-mode fibers.

+

+# SC-Connector-dat

+

+

+

+

+

+The object you're holding is an **SC (Subscriber Connector) fiber optic connector**. These connectors are commonly used in network and telecom setups for fiber optic cables. Here's a quick rundown:

+

+Connector Type: SC

+

+- **Color**: Blue typically indicates single-mode fiber (usually used for long-distance data transmission).

+- **Ferrule**: The white cylindrical part at the tip is the ferrule, which aligns the fiber and is crucial for precise data transmission.

+- **Push-pull design**: SC connectors use a push-pull mechanism for easy insertion and removal.

+

+## SC/APC

+

+

+The connector shown is an **SC/APC (Angled Physical Contact)** type fiber optic connector, but let’s get specific:

+

+Based on What I See:

+

+The **blue housing** usually indicates an **SC/UPC (Ultra Physical Contact)** connector.

+

+The **ferrule** end in your image looks flat, which is consistent with UPC rather than the angled end of an APC (which would be green and have an 8° angled polish).

+

+

+

+

+

+## SC module

+

+SC stands for Subscriber Connector.

+

+SC connectors are a type of fiber optic connector commonly used with fiber optic cables.

+

+### Features:

+

+Push-pull coupling mechanism: Allows easy insertion and removal of connectors.

+

+Duplex design: Typically used in dual-core fiber optic cables (sending and receiving signals).

+

+Durable and reliable, often used in telecommunications, data centers, and other long-distance fiber optic links.

+

+Size: Relatively large compared to other connectors like LC.

+

+

+

+

+## ref

+

+device - [[SPF-transceiver-dat]]

+

+- [[fiber-optic-dat]]

+

+# fiber-optic-connector-dat

+

+

+

+- [[LC-connector-dat]] - [[SC-connector-dat]]

+- [[fiber-optic-dat]] - [[fiber-optic]]

+- [[SPF]]

+🔶 Coaxial (RCA) SPDIF:

+

+- Uses a copper wire inside a coaxial cable.

+- Has an RCA connector (looks like those red/white/yellow plugs).

+- Carries electrical digital signals.

+- Requires a 75-ohm impedance cable for proper SPDIF transmission.

+

+

+- [[cable-dat]] - [[fiber-optic-dat]]- [[coaxial-cable-dat]] - [[POF-dat]]