Gigabit PHY in a 128-PQFP — what the 8/8 driver count means for your port density
The KSZ9021GQ is a full-duplex Gigabit Ethernet transceiver from Microchip, offering 8 drivers and 8 receivers in a single 128-PQFP package. That 8/8 count means it can handle eight separate Gigabit Ethernet channels — enough for an 8-port switch or a multi-port media converter — without external PHY chips.
Supply rail tolerance and temperature grade — the board-level constraints
Supply range is 3.135V to 3.465V — a nominal 3.3V rail with ±5% tolerance. That is standard for most 3.3V logic systems, but if your board has a poorly regulated supply that dips below 3.135V during transient load, the PHY may drop link. The operating temperature range is 0°C to 70°C, which restricts this part to commercial indoor environments — no outdoor cabinets or engine-bay installations without active cooling.
Active production — no EOL shadow, but verify date-code consistency
Lifecycle status is Active, ROHS3 compliant.