A PPGA package (plastic pin grid array) is an integrated-circuit package built on a bismaleimide-triazine (BT) laminate substrate, with a grid of press-fit pins on the underside and, on processor versions, an exposed copper heat slug on top. Intel developed it to replace ceramic PGA on high-clock parts: it runs cooler, weighs less, and costs less to build. This guide covers the construction, the thermal and mechanical numbers from Intel’s own package note, dimension tables, and where pin grid arrays still fit in 2026.

Key takeaways

• A PPGA is a pin grid array with a BT-laminate plastic body instead of ceramic; the die is wire-bonded face-up onto a nickel-plated copper heat slug.
• On Intel’s Pentium test vehicle, PPGA junction-to-case thermal resistance with a heat sink is 0.50 °C/W, versus 1.25 °C/W for the ceramic PGA (Intel AP-577).
• Standard pin pitch is 2.54 mm (100 mils); common bodies run from 68 pins (28.2 mm) to 503 pins (57.9 mm).
• Intel shipped PPGA on Mendocino-core Celerons (300A–533) in Socket 370, then moved to flip-chip PGA in 1999.
• Pin grid arrays are now legacy on desktops: AMD’s AM4 (1,331 pins) was the last mainstream PGA socket; AM5 switched to LGA in 2022.
• A plastic package is non-hermetic, so reflow-mounted PGAs follow JEDEC moisture-sensitivity handling (J-STD-020).

What is a PPGA package?

A plastic pin grid array (PPGA) is a semiconductor package that mounts the die on a laminated printed-circuit-board substrate and routes signals out through a square array of pins on the underside. It swaps the ceramic body of a traditional PGA for lower-cost organic laminate that also conducts heat better.

[IMAGE 1: labeled cross-section of a PPGA — BT laminate substrate, copper traces, wire-bonded die on a Ni/Cu heat slug, Kovar pins | alt: “PPGA package cross-section showing BT laminate substrate, heat slug, wire-bonded die, and pin grid”]

The substrate is glass-reinforced BT laminate with a glass-transition temperature (Tg) of 170–190 °C, chosen for stability through assembly (Intel AP-577). Copper traces run from gold-plated bond fingers to the pins. On CPU versions the die sits on a nickel-plated copper heat slug that also serves as a ground plane; the pins are Kovar plated with gold over nickel, and the slug and chip capacitors are solder-attached with 90/10 Sn/Pb using standard SMT steps. Because the piece part is made with ordinary PCB processing, a PPGA is cheaper to produce than a co-fired ceramic package.

PPGA vs. CPGA: the numbers that matter

Intel built the PPGA as a drop-in replacement for the ceramic PGA (CPGA). The two share footprint and I/O timing, but the plastic version wins on heat and weight. The figures below come from Intel’s AP-577 package note for the Pentium processor.

Attribute	CPGA	PPGA
Body material	Ceramic, Al bond wires	BT laminate, Au bond wires
Body thickness	2.8 mm	3.0 mm (with heat slug)
Package weight	29 g	18 g
Trace metal	Tungsten	Copper
External heat slug	No	Yes
θJC, with heat sink	1.25 °C/W	0.50 °C/W
θJC, no heat sink	1.7 °C/W	1.3 °C/W
On-package decoupling	14 nF	~120 nF
Board mount	Socket or through-hole	Socket only

Copper traces cut IR drop relative to the CPGA’s tungsten metallization, so the core sees a slightly higher supply voltage at the same setting. In a matched server-chassis test, a 120 MHz Pentium in PPGA ran 5–6 °C cooler than the same part in CPGA (Intel AP-577). The cost is ruggedness: the laminate edge is softer than ceramic, so repeated heat-sink-clip removal can chip the package.

[INTERNAL LINK: ceramic pin grid array (CPGA) → CPGA package guide]

PPGA vs. FC-PGA, BGA, and LGA

Engineers routinely mix these up. The differences come down to where the interconnect sits and whether the die faces up or down.

• PPGA: pins on a plastic body; die wire-bonded face-up over a heat slug.
• FC-PGA (flip-chip PGA): pins on a plastic body, but the die is flipped face-down onto the substrate with its backside exposed for direct cooling. Intel introduced FC-PGA in 1999 on Coppermine-core Pentium III and Celeron parts in Socket 370.
• BGA (ball grid array): solder balls instead of pins, permanently reflowed to the board. Standard in laptops and mini-PCs, where the chip is not replaceable.
• LGA (land grid array): flat contact pads on the chip; the pins move into the socket. A bent pin then damages the socket, not the CPU.

Quick rule: pins on the chip is PGA, pins in the socket is LGA, balls soldered down is BGA. A close cousin, the organic pin grid array (OPGA), applies the same organic-substrate idea to CPUs.

[INTERNAL LINK: BGA vs. LGA packaging → BGA vs. LGA comparison]

Pin count, pitch, and body size

PGA packages scale to high I/O counts, which is why processors adopted them over dual in-line packages. Pins sit on a 2.54 mm (100 mil) grid; higher-density parts use 1.27 mm (50 mil), and some later mobile PGAs went to 1 mm. Body size grows with pin count. Representative plastic PGA bodies:

Pins	Body size	Body thickness	Pin pitch
68	28.2 × 28.2 mm	3 mm	2.54 mm
120	35.1 × 35.1 mm	3 mm	2.54 mm
156	42.7 × 42.7 mm	3 mm	2.54 mm
296	49.5 × 49.5 mm	3 mm	2.54 mm
411	52.8 × 52.8 mm	3 mm	2.54 mm
503	57.9 × 57.9 mm	3 mm	2.54 mm

Source: EESemi package data.

[IMAGE 2: underside pin grid of a Socket 370 PPGA Celeron on 2.54 mm pitch | alt: “Underside of a PPGA Celeron processor showing the 2.54 mm pin grid array”]

Intel’s 296-pin staggered PPGA drawing gives body length D = 49.43–49.63 mm and pin length L = 3.05–3.30 mm (AP-577), matching the 49.5 mm row. For logic parts, National Semiconductor shipped molded plastic PGAs at 124, 159, and 175 pins (packages UP124A / UP159A / UP175A), a reminder that PPGA was never only a CPU package.

Where PPGA was used, and where PGA lives now

On the desktop, PPGA is best known from Intel’s Mendocino-core Celeron: the Celeron 300A through 533 shipped in PPGA for Socket 370, a 370-contact ZIF socket. Those parts were popular with overclockers because the low-cost package still shed heat well. Intel then moved Coppermine-generation parts to FC-PGA on the same socket family, and desktop PGA at Intel ended at Socket 478, the last Intel desktop socket to use a pin grid array before LGA 775 arrived in 2004.

AMD carried PGA far longer. Socket AM4 (2016–2022) used a 1,331-pin PGA and was the last mainstream desktop PGA socket; AM5 moved the pins into the socket as an LGA-1718 design in September 2022. So an engineer today meets PGA mainly in legacy AM4 systems, older embedded and industrial modules, and some logic and RF parts, not in new high-pin-count processors.

Design and handling notes engineers actually need

The datasheet-level details that matter when you socket, cool, or qualify a PPGA, all from Intel AP-577 unless noted:

• Insertion force: keep insertion and extraction under 100 lb, applied evenly across the pin matrix rather than on the heat slug. Measured averages ran 38–78 lb for low-insertion-force sockets; a closed ZIF socket showed about 81 lb extraction.
• Heat-sink clip: a minimum clip force of 5 lb (≈ 5 psi) is enough for full thermal contact once grease is applied; more force does not lower thermal resistance. Use a thermal interface material with conductivity above 0.8 W/m·K and volume resistivity above 1 × 10⁶ Ω·cm, and keep it electrically insulating.
• Vibration: if the combined heat-sink-plus-package mass exceeds about 135 g, the assembly can vibrate out of some type-5/7 ZIF sockets under shock and vibration. Clip the heat sink to the socket, not to the package.
• Decoupling: the PPGA carries roughly 120 nF across eight on-package capacitors to control switching noise, against 14 nF on the CPGA.
• Moisture: a plastic package is non-hermetic. Reflow-soldered PGAs (logic and RF parts) carry a JEDEC moisture-sensitivity level per J-STD-020 and must be baked and bagged accordingly; socketed CPU versions never see reflow, so popcorn cracking is not a concern for them.
• Reliability: Intel’s qualification included 1,000 cycles of −55 to 125 °C temperature cycling and 1,000 h of 85 °C / 85% temperature-humidity-bias, with no functional failures.

[INTERNAL LINK: junction-to-case thermal resistance (θJC) → understanding θJC and θJA] · [INTERNAL LINK: JEDEC moisture-sensitivity levels → MSL handling guide]

Sourcing PPGA parts today

No current CPU ships in PPGA, so treat processor-grade PPGA as end-of-life. It exists only in the used and surplus channel, where remarked and counterfeit parts are common. For legacy repair, check date codes and S-spec markings against Intel’s processor documentation and buy from traceable sources. For new designs, plastic PGA survives mainly as a logic or RF option; when a distributor lists one, confirm pin count, body size, and pitch against the datasheet before you commit a footprint, because the same pin count can appear in more than one body size.

Frequently asked questions

What is the difference between PPGA and CPGA?

Both are pin grid arrays with the same footprint and I/O timing. PPGA uses a BT-laminate plastic body with copper traces and a metal heat slug; CPGA uses a ceramic body with tungsten traces. The plastic version is lighter (18 g vs 29 g) and has lower junction-to-case thermal resistance: 0.50 °C/W vs 1.25 °C/W with a heat sink (Intel AP-577).

What socket does a PPGA processor use?

Intel’s PPGA Celeron processors use Socket 370, a 370-contact zero-insertion-force socket. PPGA parts are socket-mounted only; unlike some ceramic PGAs, they are not meant for direct through-hole soldering. Early Socket 370 boards were wired for PPGA before Intel added flip-chip parts to the same socket.

Is PPGA the same as FCPGA?

No. Both put pins on a plastic body, but PPGA wire-bonds the die face-up over a heat slug, while FC-PGA flips the die face-down so the silicon backside is exposed for cooling. Intel replaced PPGA with FC-PGA on Coppermine-core parts in 1999 for better thermal headroom at higher clocks.

What replaced PPGA packaging?

FC-PGA replaced PPGA on Intel desktop CPUs in 1999. More broadly, pin grid arrays gave way to land grid array (LGA) packaging, which moves the pins to the socket. Intel’s last desktop PGA was Socket 478; AMD’s was Socket AM4, replaced by LGA-based AM5 in 2022.

What is the pin pitch of a PPGA?

Standard PPGA pin pitch is 2.54 mm (100 mils), with finer 1.27 mm (50 mil) variants for higher pin counts. Intel’s 296-pin PPGA staggers its rows within that grid to lower insertion force. Body size scales with pin count, from about 28 mm square at 68 pins to about 58 mm square at 503 pins.

The bottom line

If you are keeping legacy hardware alive, buy PPGA processors only through traceable channels and check the markings; the package is obsolete and the used market is thick with remarks. If you are choosing a package for a new design, skip PGA for anything high-pin-count and reach for BGA or LGA instead; keep plastic PGA only where a socketed, field-replaceable part at a moderate pin count earns its place. Either way, pull the θJC and dimension numbers from the exact datasheet you are buying against. The 0.50 °C/W and 49.5 mm figures here describe Intel’s Pentium-class test vehicle, not a universal PPGA specification.