ENC28J60 Datasheet PDF – Ethernet Controller – Microchip

Part Number: ENC28J60

Function : Stand-Alone Ethernet Controller with SPI Product Brief

Package: 28-pin SSOP, SOIC, SPDIP and QFN Type

Manufacturer: Microchip Technology

Image:

enc28j60-ethernet-controller

Description

The Microchip Technology, ENC28J60 is a standalone Ethernet controller with an industry standard Serial Peripheral Interface (SPI). It is designed to serve as an Ethernet network interface for any microcontroller equipped with SPI. The ENC28J60 meets all of the specifications for IEEE 802.3. It incorporates a number of packet filtering schemes to limit incoming packets. It also provides internal DMA for fast data throughput and support for hardware assisted IP checksum calculation.

Pinout

enc28j60-datasheet-pinout

 

Features

1. IEEE 802.3 Compatible Ethernet Controller

2. Integrated MAC and 10BASE-T PHY

3. 8-Kbyte Transmit/Receive Packet Dual Port Buffer SRAM

4. Receiver and Collision Squelch Circuit

5. Supports one 10BASE-T Port with Automatic Polarity Detection and Correction

6. Programmable Automatic Retransmit on Collision

7. Programmable Padding and CRC Generation

8. Programmable Automatic Rejection of Erroneous Packets

9. 10 Mbit/s SPI Interface

Oscillator Start-up Timer

The ENC28J60 contains an Oscillator Start-up Timer (OST) to ensure that the oscillator and integrated PHY have stabilized before use. The OST does not expire until 7500 OSC1 clock cycles (300 μs) pass after Power-on Reset or wake-up from Power-Down mode occurs. During the delay, all Ethernet registers and buffer memory may still be read and written to through the SPI bus. However, software should not attempt to transmit any packets (set ECON1.TXRTS), enable reception of packets (set ECON1.RXEN) or access any MAC, MII or PHY registers during this period.

When the OST expires, the CLKRDY bit in the ESTAT register will be set. The application software should poll this bit as necessary to determine when normal device operation can begin.

LED Configuration

The LEDA and LEDB pins support automatic polarity detection on Reset. The LEDs can be connected such that the pin must source current to turn the LED on, or alternately connected such that the pin must sink current  to turn the LED on. Upon system Reset, the ENC28J60 will detect how the LED is connected and begin driving the LED to the default state configured by the PHLCON register. If the LED polarity is changed while the ENC28J60 is operating, the new polarity will not be detected until the next system Reset occurs.

ENC28J60 Datasheet PDF

KDV147 Datasheet PDF – 15V, Variable Capacitance Diode

Part Number: KDV147

Function: Variable Capacitance Diode, Silicon Epitaxial Planar Diode

Package: TO-92M Type

Manufacturer: KEC

Image and Pinouts:

KDV147 datasheet

Description

The KDV147 is a 15V silicon epitaxial planar variable capacitance diode (varactor) designed for voltage-controlled tuning applications in RF circuits, typically supplied in a compact small-signal package. It provides low series resistance and stable capacitance variation characteristics, making it suitable for frequency tuning and modulation. This device is primarily used in FM radio band tuning, VCO circuits, and RF filtering applications.

Features

  • Low series resistance with rs=0.3Ω (typ.)
  • Optimized for voltage-controlled capacitance tuning
  • Compact small-signal package
  • Silicon epitaxial planar construction for stability
  • Suitable for RF and high-frequency applications

Pinout

Absolute Maximum Ratings (Tc = 25 °C)

Parameter Symbol Value Unit
Reverse Voltage VR 15 V
Junction Temperature Tj 150 °C
Storage Temperature Tstg -55 to 150 °C

Design Notes

  • Operate strictly under reverse bias to utilize capacitance variation
  • Capacitance decreases as reverse voltage increases (nonlinear characteristic)
  • Minimize series resistance effects for high-Q tuning circuits
  • Use stable bias voltage for predictable frequency control
  • Temperature variation can affect capacitance, consider compensation if required

Typical Circuit Usage

  • Voltage-controlled oscillators (VCO)
  • RF tuning circuits in FM receivers
  • Frequency modulation circuits
  • Band-pass and notch filters with tunable response
  • PLL frequency control systems

How to Choose This Part

  • Select when low-voltage (≤15V) tuning range is sufficient
  • Ideal for FM band and low-power RF applications
  • Ensure required capacitance range matches tuning needs
  • Prefer when low series resistance is critical for Q factor
  • Consider alternative varactors for wider tuning ratios or higher voltage operation

Applications

  • FM radio band tuning
  • Wireless communication circuits
  • Signal generators and RF modulators
  • Frequency synthesizers
  • Consumer RF electronics

Alternative / Equivalent Products

  • BB109 (common varactor diode)
  • MV2109 (tuning diode alternative)
  • 1SV149 (low-voltage varactor diode)
  • BBY51 (SMD varactor option)
  • KV1235 (similar tuning diode)

Other data sheets are available within the file:

KDV147A, KDV147B, KDV147C, KDV147D

KDV147 Datasheet PDF Download


KDV147 pdf