An LQFP-176 package is a 176-lead gull-wing plastic package with a 1.4 mm nominal body, registered under JEDEC MS-026. Two geometries ship under that name: 24 × 24 mm on 0.5 mm pitch and 20 × 20 mm on 0.4 mm pitch. Confirm which one your part number uses before you place a footprint. Below are the mechanical numbers, the pin-numbering rules, a worked land pattern, and the thermal penalty against the same die in a BGA.
Key takeaways
- LQFP-176 fixes a lead count and a lead style. It does not fix a single footprint.
- The 24 mm version runs 24.100 mm max across the body and 26.100 mm max across the lead tips.
- There are 44 leads per side. Corner leads land at pins 1, 44, 45, 88, 89, 132, 133 and 176.
- A nominal-density land pattern works out near 0.30 mm × 1.55 mm pads on a 26.80 mm outer span.
- Renesas measures 44.5 °C/W for its 176-lead LQFP against 32.4 °C/W for the same die in a 176-ball BGA.
- MSL 3 is the usual rating. That is 168 h of floor life before a bake is required.
What is an LQFP-176 package?
LQFP-176 is a 176-lead low-profile quad flat package with gull-wing leads on all four sides, 44 leads per side, and a 1.4 mm nominal body thickness registered under JEDEC MS-026. The common production version measures 24 × 24 mm on 0.5 mm lead pitch, with lead tips spanning 26 mm.
The “low profile” designation is the 1.4 mm body. MS-026 is registered as the 2.00 mm footprint family, which is why the lead tips sit 1.00 mm beyond the body edge on each side: a 24 mm body gives a 26 mm span, and a 20 mm body gives 22 mm. JEDEC currently lists MS-026 at Issue D.
[IMAGE 1: top and side view of a 176-lead LQFP with body, lead span and standoff called out | alt: “LQFP-176 package outline showing 24 mm body and 26 mm lead span”]
LQFP-176 dimensions
The table below is ST’s mechanical data for its LQFP176, taken from the STM32F405xx/STM32F407xx datasheet, Doc ID 022152 Rev 3, Table 93. Every STM32 in this package shares it.
| Symbol | Dimension | Min | Typ | Max |
| A | Overall height | 1.600 mm | ||
| A1 | Standoff | 0.050 mm | 0.150 mm | |
| A2 | Body thickness | 1.350 mm | 1.450 mm | |
| b | Lead width | 0.170 mm | 0.270 mm | |
| c | Lead thickness | 0.090 mm | 0.200 mm | |
| D, E | Body size | 23.900 mm | 24.100 mm | |
| e | Lead pitch | 0.500 mm | ||
| HD, HE | Lead span | 25.900 mm | 26.100 mm | |
| L | Lead foot length | 0.450 mm | 0.750 mm | |
| L1 | Lead length | 1.000 mm | ||
| ZD, ZE | Corner to first lead | 1.250 mm | ||
| ccc | Coplanarity | 0.080 mm | ||
| k | Lead angle | 0° | 7° |
Renesas publishes complementary figures on drawing PLQP0176KE-B for the same 24 × 24 body: standoff 0.125 ±0.075 mm, lead width 0.22 +0.05/−0.04 mm, lead thickness 0.145 +0.055/−0.045 mm, and lead form angle 3° +7°/−3°.
One discrepancy matters. ST caps overall height at 1.600 mm. The Renesas drawing states 1.7 mm max, because it specifies the body as 1.4 ±0.1 mm rather than 1.35 to 1.45 mm. If your enclosure clearance sits under 1.7 mm, pull the specific manufacturer drawing rather than assuming the JEDEC nominal.
The two LQFP-176 geometries
This is where library errors originate. Microchip’s PIC32MZ Graphics (DA) family, document DS60001361J, lists its 176-pin LQFP as 20 × 20 mm on 0.4 mm contact pitch. ST, Renesas and Toshiba all use 24 × 24 mm on 0.5 mm. Same lead count, incompatible boards.
| Attribute | 24 × 24 mm version | 20 × 20 mm version |
| Body size | 24.0 mm square | 20.0 mm square |
| Lead pitch | 0.5 mm | 0.4 mm |
| Lead span | 26.0 mm nominal | 22.0 mm nominal (MS-026 2.00 mm footprint) |
| Leads per side | 44 | 44 |
| Body thickness | 1.4 mm nominal | 1.4 mm nominal |
| Typical hosts | STM32F4/F7/H7, Renesas RA6M3, Toshiba LQFP176-P-2424-0.50A | Microchip PIC32MZ DA |
| Land area consumed | approx. 718 mm² courtyard | approx. 460 mm² courtyard |
The 0.4 mm version buys back roughly a third of the board area. It also costs process margin: pad widths drop toward 0.25 mm and the copper gap tightens accordingly.
A second naming trap: TQFP176 describes the same lead frame at a 1.0 mm body. The land pattern is identical, the height is not. Stencil vendors often list a part as “LQFP-176/TQFP-176” for exactly that reason.
LQFP-176 pinout
The package defines geometry, not function. There is no such thing as a generic LQFP-176 pinout, and any page that shows you one is showing you a specific device.
What the package does fix:
- 44 leads per side, four sides.
- Pin 1 sits at a corner, marked by a molded or laser index feature.
- Numbering runs counter-clockwise when viewed from the top.
- Corner leads therefore fall at pins 1, 44, 45, 88, 89, 132, 133 and 176, as printed on the Renesas PLQP0176KE-B drawing.
- The first lead centre sits 1.250 mm in from the body corner.
[IMAGE 2: pin numbering diagram with corner pin numbers labelled | alt: “LQFP-176 pinout numbering with 44 pins per side and corner pins 1, 44, 45, 88”]
Cross-check the pinout figure against the pin-function table in the same datasheet before you commit a symbol. These figures do carry errors: in ST’s STM32H747I datasheet DS12930 Rev 1, the LQFP176 pinout drawing swapped pins 158 and 159, showing VSS where PG14 belongs, while the pin table later in the same document had them correct. ST acknowledged the error on its community forum and scheduled a fix for the following revision. A 176-lead symbol built from the figure alone would have carried that fault into the netlist.
LQFP-176 footprint and land pattern
Work from the tolerance table, not from a library default. IPC-7351B builds each pad from the lead extremes plus a toe, heel and side solder-fillet goal. At Level N (nominal, standard reflow production) the toe and heel goals are 0.35 mm each.
Worked calculation, 24 × 24 mm version, Level N:
- Outer pad edge = HD max ÷ 2 + toe = 26.100 ÷ 2 + 0.35 = 13.40 mm from centre
- Inner pad edge = (HD min ÷ 2 − L max) − heel = (12.95 − 0.750) − 0.35 = 11.85 mm from centre
- Pad length = 13.40 − 11.85 = 1.55 mm
- Pad width, side goals reduced for fine pitch: 0.30 mm
- Courtyard = 26.80 mm outer span + 0.25 mm per side = 27.30 mm square
| Parameter | Value | Cross-check |
| Pad width | 0.30 mm | Holtek specifies 0.30 mm for all 0.5 mm pitch LQFP |
| Pad length | 1.55 mm | Holtek uses 1.65 mm |
| Pad span, outer to outer | 26.80 mm | Holtek gives 25.4 mm BSC for the 24 mm body at 0.4 mm pitch |
| Copper gap between pads | 0.20 mm | Sets the bridging risk |
| Courtyard | 27.30 mm square | Level N excess of 0.25 mm per side |
IPC’s side-fillet goal shrinks, and can go negative, once pitch drops below 0.625 mm. That is why a 0.5 mm pitch pad lands at 0.28 to 0.30 mm rather than the 0.38 mm the coarse-pitch formula would produce.
Three consequences follow from the 0.20 mm copper gap:
Solder mask. A mask sliver between pads needs about 0.10 mm of web to survive fabrication. With a 0.20 mm gap and ±0.05 mm registration tolerance, you are at the limit. Many designers run mask-defined dams only if the fabricator confirms the capability, and otherwise open the mask across the row.
Stencil. Keep apertures at pad size or slightly reduced in width. Widening apertures to chase fillet height is the fastest route to bridging on 44-lead rows.
Escape routing. A 0.10 mm trace between two pads leaves 0.05 mm to each pad. That is below standard-class fabrication for most shops, so the inner ranks of a 176-lead device generally escape through vias rather than between pads. Budget the layer count before you commit to the package.
[IMAGE 3: land pattern drawing with pad dimensions and courtyard boundary | alt: “LQFP-176 footprint land pattern with 0.30 mm by 1.55 mm pads on 0.5 mm pitch”]
What the package costs you thermally
Renesas publishes θJA for five packages carrying the identical RA6M3 die, all measured on a JESD51-7 four-layer board inside a JESD51-2 enclosure. Application note R01AN6034EJ0101 Rev 1.01, Table 3.1:
| Package | Renesas code | θJA | Delta vs LQFP-176 |
| 145-pin LGA | PTLG0145KA-A | 25.9 °C/W | −18.6 |
| 176-pin BGA | PLBG0176GE-A | 32.4 °C/W | −12.1 |
| 176-pin LQFP | PLQP0176KB-A | 44.5 °C/W | reference |
| 144-pin LQFP | PLQP0144KA-B | 45.7 °C/W | +1.2 |
| 100-pin LQFP | PLQP0100KB-B | 46.8 °C/W | +2.3 |
Read the last column carefully. Moving from 100 to 176 leads on the same die improves θJA by 2.3 °C/W, roughly 5%. Moving from the 176-lead LQFP to the 176-ball BGA improves it by 12.1 °C/W, roughly 27%. Lead count is not a thermal strategy. Package family is.
At 44.5 °C/W and a 125 °C junction limit, a device dissipating 500 mW reaches a junction temperature about 22 °C above ambient. In a 105 °C enclosure that leaves usable margin. At 1.5 W it does not, and no amount of copper under a peripheral-leaded package recovers it.
Moisture, reflow and handling
Large plastic bodies in this class are typically rated MSL 3: JLCPCB lists the XHSC HC32F4A0SITB in LQFP-176 (24 × 24) at MSL 3. Under J-STD-033 that allows 168 h of floor life at 30 °C and 60% RH after the dry bag is opened, then a bake before reflow.
Peak reflow classification for a body under 2.5 mm thick is 260 °C under IPC/JEDEC J-STD-020. Your profile’s peak package temperature must stay at or below the classification temperature, not above it.
Coplanarity is the mechanical parameter that decides yield. ST specifies ccc at 0.080 mm max across all 176 leads. A single corner lead lifted beyond that produces an open that visual inspection will miss and only AOI or X-ray will catch. Handle trays flat, and reject any part with visible lead damage rather than attempting a straighten.
Who ships LQFP-176
| Manufacturer | Package designation | Body and pitch | Representative devices |
| STMicroelectronics | LQFP176 | 24 × 24 mm, 0.5 mm | STM32F429, STM32F779, STM32H743, STM32H747 |
| Renesas | PLQP0176KB-A / PLQP0176KE-B | 24 × 24 mm, 0.5 mm | RA6M3 (R7FA6M3AH3CFC) |
| Toshiba | LQFP176-P-2424-0.50A | 24 × 24 mm, 0.5 mm | TXZ family devices |
| Infineon | PG-LQFP-176-22, -20, -12, -6 | Per variant | AURIX TC series, TC1784, XC22xx |
| Microchip | 176-pin LQFP | 20 × 20 mm, 0.4 mm | PIC32MZ DA (PIC32MZ2064DAH176) |
| XHSC | LQFP-176 (24 × 24) | 24 × 24 mm, 0.5 mm | HC32F4A0SITB |
Availability is healthy across the 24 mm variant, and the package is not a supply bottleneck in the way fine-pitch BGA can be. LCSC lists the STM32F429IIT6 in LQFP176 from around $5.48 at the time of writing, and DigiKey shows the same part and the STM32H743IIT6 shipping from stock. Prices in this class move, so treat the figure as a starting point and check live.
For second sourcing, note that a pin-compatible swap almost never exists across vendors. The realistic second source is a different flash or temperature grade within the same family, in the same 24 × 24 body.
Five mistakes that cause board spins
- Assuming 0.5 mm pitch. If the part is a PIC32MZ DA, it is 0.4 mm on a 20 mm body. Check the drawing, not the lead count.
- Building the symbol from the pinout figure. Datasheet figures carry errors. Build from the pin-function table and cross-check.
- Using a coarse-pitch pad width. The generic gull-wing formula gives 0.38 mm, which leaves a 0.12 mm gap at 0.5 mm pitch and bridges.
- Ignoring the height spread. ST caps at 1.600 mm, Renesas at 1.7 mm. Enclosures designed to the JEDEC nominal have failed on the second source.
- Treating pin count as thermal headroom. The Renesas data shows 176 leads buying 2.3 °C/W over 100 leads. If you need thermal margin, change package family.
[IMAGE 4: side-by-side of correct and oversized pad geometry at 0.5 mm pitch | alt: “LQFP-176 land pattern comparison showing correct 0.30 mm pad width against bridging risk”]
Frequently asked questions
What are the dimensions of an LQFP176 package?
The common version has a body of 24.100 mm max square, a lead span of 26.100 mm max, and an overall height of 1.600 mm max with a 0.050 to 0.150 mm standoff, on 0.5 mm lead pitch. A second version exists at 20 × 20 mm on 0.4 mm pitch, used by Microchip’s PIC32MZ DA family.
How many pins are on each side of an LQFP-176?
There are 44 leads per side across all four sides. Numbering starts at the indexed corner and runs counter-clockwise viewed from above, so the corner leads are pins 1, 44, 45, 88, 89, 132, 133 and 176. The first lead centre sits 1.250 mm in from the body corner.
What is the difference between LQFP176 and TQFP176?
Body thickness. LQFP is the 1.4 mm nominal body, TQFP is the 1.0 mm body, and both are registered under JEDEC MS-026. The lead frame, lead pitch and land pattern are the same, so the footprint is shared. Only the height budget in the enclosure changes.
What pad size should I use for an LQFP-176 footprint?
At 0.5 mm pitch, use pads of roughly 0.30 mm wide by 1.55 mm long, positioned so the outer pad edges span 26.80 mm. Holtek’s published footprint guide specifies 0.30 mm width for all 0.5 mm pitch LQFP bodies. Wider pads increase bridging risk without improving joint strength.
Is LQFP-176 good enough thermally, or should I move to BGA?
Renesas measures 44.5 °C/W for the 176-lead LQFP against 32.4 °C/W for the same die in a 176-ball BGA, on identical four-layer test boards. Below roughly 1 W the LQFP is usually adequate. Above that, the 27% improvement from the BGA is difficult to replace with board copper alone.
The decision
Choose the LQFP-176 when your device dissipates under about 1 W, when you need optical inspection and rework access, and when board area at 27 mm square is available. It is the lower-risk choice for prototypes, low-to-mid volume industrial builds, and any product where an EMS without X-ray will assemble it.
Move to a BGA when dissipation exceeds roughly 1 W, when the 27 mm courtyard does not fit, or when your layer budget cannot absorb via-based escape routing from 44-lead rows.
Before release, do three things. Pull the manufacturer drawing for your exact part number and confirm body size and pitch. Verify the height max against your enclosure. Check your library pad width against the 0.30 mm figure above, not against whatever the CAD tool generated.
Internal links
- [INTERNAL LINK: BGA vs QFP package selection → package selection guide]
- [INTERNAL LINK: IPC-7351B land pattern density levels → PCB footprint standards]
- [INTERNAL LINK: MSL ratings and floor life → component handling and storage]
- [INTERNAL LINK: fine-pitch escape routing → high pin count PCB layout]
External sources
- Renesas, package drawing PLQP0176KE-B: https://www.renesas.com/en/document/psc/package-drawing-lfqfp-176pin-plqp0176ke-b
- Renesas, R01AN6034EJ0101 Rev 1.01, RA6M3 thermal resistances: https://www.renesas.com/en/document/apn/notes-ra6m3-group-high-temperature-operation-rev101
- Microchip, PIC32MZ Graphics (DA) Family Data Sheet DS60001361J: https://ww1.microchip.com/downloads/aemDocuments/documents/OTH/ProductDocuments/DataSheets/PIC32MZ-Graphics-DA-Family-Data-Sheet-DS60001361J.pdf
- Toshiba, package LQFP176-P-2424-0.50A: https://toshiba.semicon-storage.com/us/semiconductor/design-development/package/detail.LQFP176-P-2424-0.50A.html
- Holtek, Recommended Footprints for QFP Series Rev 1.10: https://www.holtek.com/webapi/106680/Footprints_for_QFP_LQFP_TQFP_Series_20230119.pdf/7f1471e7-8267-4723-923c-86b41720b4a6
