An LQFP-256 package measures 28.00 mm square across the body, 30.00 mm across the lead tips, and carries 64 gull-wing leads per side on a 0.40 mm pitch. Body thickness is 1.40 mm; overall height tops out at 1.70 mm. Those numbers are settled. The harder question is whether you should specify one, because on the same 28 mm body a 208-lead LQFP usually delivers more usable I/O, from stock, for less money.

Key takeaways

• Body 28.00 mm ±0.20 square, lead span 30.00 mm ±0.20, pitch 0.40 mm, 64 leads per side, per the Renesas PLQP0256LC-A outline.
• Corner pins fall at 1, 64/65, 128/129 and 192/193; numbering runs counterclockwise from the index mark.
• A nominal-density IPC-7351B land pattern works out to 0.20 mm × 1.80 mm pads, 31.20 mm toe-to-toe and 27.60 mm heel-to-heel.
• 256 leads is not 256 signals. The Renesas SH7269 in this package exposes 149 usable I/O, fewer than a 208-lead STM32F7 in the identical body.
• Active LQFP-256 devices are rare and effectively single-sourced. Confirm availability before you commit the footprint.

LQFP-256 package dimensions and mechanical data

The LQFP-256 is a low-profile quad flat package carrying 256 gull-wing leads, 64 on each side of a 28.00 mm square plastic body. Lead pitch is 0.40 mm and the span across opposing lead tips is 30.00 mm. Body thickness is 1.40 mm, with a maximum seated height of 1.70 mm.

Every figure below traces to the Renesas package outline for the 256-pin LFQFP, drawing code S256GD-40-8EV-1, package code PLQP0256LC-A. Treat it as representative of the outline rather than as a universal specification, and check the drawing that ships with your specific device.

[IMAGE 1: LQFP-256 outline, top and side view, with body, lead span, pitch and height callouts | alt: “LQFP-256 package dimensions showing 28 mm body, 30 mm lead span and 0.40 mm pitch”]

Parameter	Value (Renesas PLQP0256LC-A, drawing S256GD-40-8EV-1)
Lead count	256 total, 64 per side
Body size	28.00 mm ± 0.20, square
Lead span, tip to tip	30.00 mm ± 0.20, square
Lead pitch	0.40 mm, true position
Body thickness	1.40 mm (+0.10 / −0.05)
Maximum height	1.70 mm
Lead width	0.18 mm ± 0.05
Plated lead thickness	0.145 mm ± 0.05
Foot (contact) length	0.60 mm ± 0.15
Lead extension past body	1.00 mm ± 0.20
Lead form angle	3° +5° / −3°
Lead true position	within 0.10 mm at maximum material condition
Family registration	JEDEC MS-026 (Amkor lists 256/280-lead 28 × 28 mm under MS-026)
Shipping media	JEDEC tray, 4 × 9 matrix, 36 units per tray (Amkor)

Amkor lists the 28 × 28 mm LQFP body, the one used for both 256 and 280 leads, under JEDEC MS-026, shipped in a 4 × 9 tray matrix at 36 units per tray. SPIL quotes the same family envelope: 7 × 7 mm to 28 × 28 mm bodies, 32 to 256 leads. Renesas indexes the part as LFQFP, the fine-pitch designation, while distributors file it as 256-LQFP. Search both strings or you will miss real inventory.

Pin numbering, orientation and the pinout question

A package does not have a pinout. It has a numbering convention; the pinout belongs to the silicon inside it. Two devices in the same LQFP-256 outline can assign completely different functions to pin 1. What the package fixes is where pin 1 sits and which way the count runs.

For the LQFP-256, pin 1 sits adjacent to the index mark and numbering advances counterclockwise viewed from the top. The Renesas outline places corner pins at 1, at 64 and 65, at 128 and 129, and at 192 and 193, closing the loop at 256.

[IMAGE 2: LQFP-256 pin numbering diagram with corner pins labeled | alt: “LQFP-256 pin numbering with corner pins 1, 64, 65, 128, 129, 192 and 193”]

One consequence is worth checking early. Sixty-three pitch intervals at 0.40 mm span 25.20 mm on a 28.00 mm body, leaving 1.40 mm between the body edge and the outermost lead centerline on each side. That 1.40 mm end margin is the only space you have for corner fiducials, pin-1 marking and whatever keepout your assembler asks for.

The LQFP-256 footprint, calculated

Most CAD libraries hand you a pattern with no derivation. Here is the arithmetic, so the numbers survive a design review.

Inputs come straight off the outline drawing: lead span L = 30.00 ±0.20 mm, foot length T = 0.60 ±0.15 mm, lead width W = 0.18 ±0.05 mm, pitch 0.40 mm. Solder-joint goals for a nominal-density gull-wing pattern at fine pitch are 0.50 mm toe, 0.35 mm heel and −0.02 mm side. The side goal turns negative below 0.625 mm pitch, and that negative number is what keeps 0.40 mm pitch copper from bridging. Fabrication and placement tolerances are assumed at 0.05 mm and 0.025 mm; substitute your own fabricator’s numbers.

Land-pattern parameter	Value	Derivation
Toe-to-toe span, Z	31.20 mm	L min 29.80 + 2 × 0.50 toe + RMS 0.40
Heel-to-heel span, G	27.60 mm	S max 29.30 − 2 × 0.35 heel − RMS 1.00
Pad length	1.80 mm	(Z − G) / 2
Pad width, X	0.20 mm	W min 0.13 + 2 × (−0.02) side + RMS 0.11
Clear space between pads	0.20 mm	0.40 pitch − 0.20 pad
Pads per side	64	256 / 4
IPC-7351B pattern name	QFP40P3000X3000X170-256N	pitch, lead spans, height, lead count, nominal density

[IMAGE 3: calculated land pattern with Z, G and pad dimensions marked | alt: “LQFP-256 footprint land pattern, 31.20 mm toe span and 0.20 by 1.80 mm pads”]

Two consequences drop out. First, the pad inner edge sits 13.80 mm from package center while the body edge sits at 14.00 mm, so the pads run 0.20 mm under the package body. Plan solder mask and assembly silkscreen around that overlap. Second, 0.20 mm pads on a 0.40 mm pitch leave 0.20 mm of clear space between adjacent copper. A 0.10 mm trace needing 0.10 mm clearance on each side wants 0.30 mm, so nothing routes between pads. All 256 nets escape outward, which is precisely why an LQFP-256 still fans out on four layers when a comparable ball grid array will not.

Stencil apertures and paste release

A 0.20 × 1.80 mm aperture in a 0.100 mm foil gives an area ratio of 0.90. Step to a 0.127 mm foil and it falls to 0.71. Both clear the 0.66 area-ratio floor that stencil houses apply to fine-pitch work, but the thicker foil deposits about 27 percent more paste per joint and moves you toward bridging rather than away from it.

Specify the 0.100 mm foil for a board whose finest pitch is the LQFP-256. If thicker sections elsewhere force a heavier foil, ask for a local step-down over this footprint rather than accepting the extra volume.

What actually ships in an LQFP-256

The package exists. The device catalog barely does. Searching distributor package taxonomies in August 2026 returns Renesas SuperH parts and very little else in an active 256-lead LQFP.

The Renesas SH7269 is the reference example. The R5S72690W266FP#V0 is a 266 MHz SH2A-FPU with 2.5 MB of on-chip SRAM, ROMless, 3.0 V to 3.6 V, rated −20 °C to +85 °C and still marked Active. DigiKey does not stock it: factory lead time is 18 weeks and it sells in 24-piece trays at $26.28 per unit.

Read the I/O count before you celebrate the lead count. That device exposes 149 usable I/O. The remaining 107 leads are supplies, grounds, references, clocks and mode pins. Forty-two percent of the package is spent on things that are not signals.

LQFP-256, LQFP-208 or a 256-ball BGA

Package	Body / area	Pitch	Example device	Usable I/O	Price and availability (checked Aug 2026)
LQFP-256	28 × 28 mm / 784 mm²	0.40 mm	Renesas SH7269 (R5S72690W266FP#V0)	149	$26.28 each in 24-piece trays; not stocked, 18-week factory lead time
LQFP-208	28 × 28 mm / 784 mm²	0.50 mm (derived: 52 leads per side)	ST STM32F746BGT6	168	$17.02 at qty 1; 2,165 in stock
FTBGA-256	17 × 17 mm / 289 mm²	1.00 mm ball pitch (derived: 16 × 16 array)	AMD XC7A35T-1FTG256C	170	$44.52 at qty 1; 516 in stock

The comparison is uncomfortable for the LQFP-256. An STM32F746BGT6 in a 208-lead LQFP occupies the identical 28 × 28 mm body, runs a 25 percent coarser 0.50 mm pitch, offers 168 usable I/O against 149, costs $17.02 in single quantities and sits in stock in the thousands.

[IMAGE 4: board-area comparison of LQFP-256, LQFP-208 and 256-ball FTBGA | alt: “LQFP-256 board area compared with LQFP-208 and a 256-ball fine-pitch BGA”]

Moving to a 256-ball fine-pitch BGA buys 170 usable I/O in 289 mm² of board area, 37 percent of what the quad flat pack occupies. You pay for it in escape routing and layer count. The case for an LQFP-256 therefore narrows to one situation: you need that specific silicon, and it ships in nothing else.

Layout, thermal and assembly notes that decide yield

The PLQP0256LC-A outline shows no exposed thermal pad, so every watt leaves through 256 leads and the copper they land on. Pour continuous ground under the part and resist the urge to thermally relieve the escape region.

A 28 mm body at 0.40 mm pitch is a warpage problem waiting to happen. Coplanarity across a lead field that wide limits yield well before solder chemistry does. Keep the package away from board edges and depanel routes, avoid mounting another large package directly opposite it on the far side of the board, and qualify the reflow profile with daisy-chain dummies before committing real silicon. TopLine sells LQFP256 daisy-chain parts for exactly this.

Lead form on this outline is 3° +5°/−3°, with each lead centerline held within 0.10 mm of true position at maximum material condition. Set your AOI placement limits against that number, not against a generic fine-pitch default.

Sourcing, lifecycle and counterfeit checks

• Search LFQFP as well as LQFP. Renesas and other Japanese suppliers use the fine-pitch designation, and a search on LQFP-256 alone hides stock that exists under the other name.
• Treat any LQFP-256 design as single-sourced until proven otherwise, and recheck status quarterly. One RS listing for the P266FP variant of the same die already shows as no longer stocked while the W266FP variant remains active.
• Legacy high-lead-count quad flat packs are a favored counterfeit target because they are easy to remark and hard to test. Buy from franchised distribution, keep tray labels with the lot, and if broker stock is unavoidable, X-ray a sample and check lead coplanarity and date-code consistency across the whole tray.

Frequently asked questions

What are the dimensions of an LQFP-256 package?

The body is 28.00 mm ±0.20 square and the span across opposing lead tips is 30.00 mm ±0.20, per the Renesas PLQP0256LC-A outline. Body thickness is 1.40 mm with a 1.70 mm maximum height. Lead width is 0.18 ±0.05 mm, foot length is 0.60 ±0.15 mm, and the leads extend 1.00 mm beyond the body edge.

What is the pin pitch of an LQFP-256?

0.40 mm, held as a true-position dimension. That is the finest pitch in general LQFP use. A 208-lead part in the same 28 mm body runs 0.50 mm. Below 0.625 mm pitch, IPC-7351B applies a negative side-fillet goal, so the copper pad ends up deliberately narrower than the maximum lead width.

How many pins per side does an LQFP-256 have?

Sixty-four per side. Corner pins are 1, 64 and 65, 128 and 129, and 192 and 193. Sixty-three pitch intervals at 0.40 mm cover 25.20 mm of the 28.00 mm body edge, which leaves 1.40 mm of margin at each end for marking and fiducials.

Is LQFP-256 the same as LFQFP-256 or TQFP-256?

LFQFP-256 and LQFP-256 describe the same 1.40 mm-thick outline; LFQFP is the fine-pitch designation used by Renesas and other Japanese suppliers. TQFP is a different, thinner family at roughly 1.0 mm body thickness. Compare drawings rather than acronyms before you reuse a footprint.

Can you hand-solder an LQFP-256?

Yes, with drag soldering, plenty of flux and magnification, but do not plan production around it. At 0.40 mm pitch with 0.20 mm between pads, rework yield falls quickly, and a 256-lead part on a 28 mm body will start lifting pads if you reflow the same site repeatedly.

The decision

Specify an LQFP-256 only when the silicon you need ships in nothing else. If the same die is offered in another package, take the 208-lead LQFP in the same 28 mm body: coarser pitch, more usable I/O, better availability, lower price.

If board area is the binding constraint and your stackup already runs four or more layers, take the 256-ball BGA and spend the budget on escape routing rather than on a fine-pitch quad flat pack that costs you 2.7 times the area. Either way, build the footprint from the outline drawing and the arithmetic above, not from a library part nobody has checked.