G2401CG 100/1000BASE-T Surface Mount Discrete LAN Transformer Module (24-Pin SOP)

The G2401CG is an industry-standard, high-performance single-port Gigabit Ethernet (100/1000 BASE-T) discrete surface-mount pulse transformer module. Housed in an ultra-low-profile 24-Pin SOP (4.5 mm Max. height) open-header package, it integrates 4 symmetrical 1CT:1CT isolation channels and cable-side common-mode chokes. Engineered for network routers, multi-port switches, carrier-grade telecom cards, and embedded IPC motherboards, it provides 1500 Vrms dielectric isolation and superior signal transmission margins across the 0.5–100 MHz spectrum.

Specifications of G2401CG Gigabit Ethernet Transformer

Electrical Specifications (@ 25°C)

G2401CG Datasheet - Mechanical and Schematic

Internal Schematic & Pinout Architecture

The G2401CG integrates four symmetrical differential channels. The integrated common mode chokes (CMC) are positioned on the Line Side (Pins 13–24) to eliminate high-frequency common-mode EMI noise before reaching the system ground.

PHY SIDE (CHIP CONNECTIONS)                                LINE SIDE (RJ45 CONNECTIONS)
  Pin 2  (TD1+) ───┐ 1CT:1CT ┌─── Common Mode ─── Pin 23 (MX1+)
                   )         (       Choke
  Pin 3  (TD1-) ───┴─────────┴─────────────────── Pin 22 (MX1-)
  Pin 1  (TCT1) ─── Center Tap                    Pin 24 (MCT1) ─── Center Tap

  Pin 5  (TD2+) ───┐ 1CT:1CT ┌─── Common Mode ─── Pin 20 (MX2+)
                   )         (       Choke
  Pin 6  (TD2-) ───┴─────────┴─────────────────── Pin 19 (MX2-)
  Pin 4  (TCT2) ─── Center Tap                    Pin 21 (MCT2) ─── Center Tap

  Pin 8  (TD3+) ───┐ 1CT:1CT ┌─── Common Mode ─── Pin 17 (MX3+)
                   )         (       Choke
  Pin 9  (TD3-) ───┴─────────┴─────────────────── Pin 16 (MX3-)
  Pin 7  (TCT3) ─── Center Tap                    Pin 18 (MCT3) ─── Center Tap

  Pin 11 (TD4+) ───┐ 1CT:1CT ┌─── Common Mode ─── Pin 14 (MX4+)
                   )         (       Choke
  Pin 12 (TD4-) ───┴─────────┴─────────────────── Pin 13 (MX4-)
  Pin 10 (TCT4) ─── Center Tap                    Pin 15 (MCT4) ─── Center Tap

Mechanical Dimensions & Recommended PCB Layout

• Package Footprint: 24-Pin Surface Mount SOP (15.1 mm length × 10.0 mm total span width).
• Component Height: 4.5 mm Max.
• Lead Pitch: 0.99 mm
  • 11 × 0.99 mm = 10.89 mm center-to-center span.
• Coplanarity: ≤0.10 mm across all 24 solder leads.
• Recommended Solder Pad Geometry:
  • Pad Width: 0.64 mm
  • Pad Length: 1.78 mm
  • Total Outer Span: 11.2 mm

Frequently Asked Questions

Q1: What is the main difference between G2401CG and an RJ45 Magjack?

Answer: The G2401CG is a discrete surface-mount (SMD) transformer module without an integrated RJ45 jack. It is soldered directly onto the PCB, allowing hardware engineers to pair it with multi-port RJ45 connectors (such as 1x4 or 2x8 ganged jacks) or custom low-profile connectors, whereas a Magjack combines the transformer and the connector into a single bulky housing.

Q2: Is G2401CG compatible with Pulse H5007NL and Bothhand GST5009 LF?

Answer: Yes. G2401CG features an identical 24-pin SOP layout, a 0.99 mm pin pitch, 1CT:1CT turns ratio, and 350 µH inductance, making it an exact pin-to-pin, drop-in replacement that requires zero changes to your existing PCB artwork.

Q3: Why is 4.5 mm height significant for discrete LAN magnetics?

Answer: The ultra-low profile height of 4.5 mm allows the G2401CG to fit into extremely tight vertical spaces, such as low-profile PCIe expansion cards, blade servers, compact set-top boxes, and thin-client networking terminals.