Post: SSOP-16 Package: Dimensions, Pinout and Footprint

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SSOP-16 Package: Dimensions, Pinout and Footprint

SSOP-16 names at least three different packages. The mainstream one is JEDEC MO-150: 0.65 mm lead pitch, a 5.0–5.6 mm body width, a 5.9–6.5 mm body length, a 7.4–8.2 mm lead span and 2.0 mm maximum height. A second family runs 0.635 mm pitch on a 3.9 mm body. Build the SSOP-16 package footprint from the wrong family and the leads miss the pads by roughly a millimeter per side.

Key takeaways

MO-150 geometry, per Texas Instruments drawing DB0016A (4220763/A, 05/2022): 0.65 mm pitch, body 5.0–5.6 mm × 5.9–6.5 mm, lead span 7.4–8.2 mm, 2.0 mm max height, foot length 0.55–0.95 mm.
The other SSOP-16 is 0.635 mm pitch on a 3.81–3.99 mm body. Analog Devices ships that outline as GN16; Amkor and TI register the same geometry as QSOP under MO-137.
The package defines no pinout. On the SN74HC595, pin numbering is identical across SOIC, SSOP, TSSOP, SOP, PDIP and CDIP.
TI’s recommended land pattern: 16 pads of 1.85 mm × 0.45 mm on 0.65 mm pitch, rows on 7.00 mm centers, giving an 8.85 mm outer span and a 5.15 mm inner gap.
Richtek publishes an SSOP-16 land of 6.80 mm outer span and 4.20 mm inner gap. Same package name, 2.05 mm narrower.
Thermally the part sits mid-pack: 82 °C/W junction-to-ambient versus 73 °C/W for SOIC-16 and 108 °C/W for TSSOP-16 on the same die.

What the name SSOP-16 actually specifies

Shrink Small Outline Package describes a lead form and a philosophy, not one drawing. JEDEC registered several outlines that vendors sell under the same four characters, and the 16-lead versions differ in every dimension that matters to a land pattern.

The registration that most datasheets point to is MO-150, titled in the JEDEC JEP95 index as a plastic shrink small outline package with 5.3 mm body width, 0.65 mm pitch and 1.25 mm lead length. Analog Devices marks its 16-lead SSOP drawing RS-16 as compliant to MO-150-AC; TI notes MO-150 as the reference on DB0016A.

Table 1. Three geometries that all get called SSOP-16

Sold as	JEDEC ref	Pitch (mm)	Body W × L (mm)	Lead span (mm)	Max height (mm)	Vendor designations
SSOP-16, 5.3 mm	MO-150	0.65	5.0–5.6 × 5.9–6.5	7.4–8.2	2.00	TI DB0016A; ADI RS-16; NXP SOT338-1
SSOP-16, 3.9 mm (QSOP-16)	MO-137	0.635	3.81–3.99 × 4.80–4.98	5.82–6.20	1.75	ADI/LTC GN16; TI DBQ; Amkor QSOP
SSOP16, 4.4 mm (a TSSOP)	MO-153	0.65	4.3–4.5 × 4.9–5.1	6.2–6.6	1.20	TI PW0016A; socket listings “SSOP16-4.4-0.65”

Two vendors make the point on their own websites. Nisshinbo Micro Devices publishes separate package pages for SSOP16 and SSOP-16. Toshiba lists its 16-lead part as SSOP16-P-225-0.65B, a designation that carries the pitch but not the JEDEC variation letter.

SSOP-16 dimensions you can design to

An SSOP-16 package in the MO-150 family measures 5.0 to 5.6 mm across the body and 5.9 to 6.5 mm along it, with leads on 0.65 mm pitch, a 7.4 to 8.2 mm span across the gull-wing feet, and a seated height of 2.0 mm maximum. Standoff is 0.05 mm minimum.

Table 2. MO-150 SSOP-16, two independent drawings compared

Parameter	TI DB0016A (4220763/A)	ADI RS-16
Lead pitch	0.65 (14 spaces, 4.55 total)	0.65 BSC
Body width	5.0–5.6	5.00–5.60
Body length	5.9–6.5	5.90–6.50
Lead span (tip to tip)	7.4–8.2 typ	7.40–8.20
Overall height	2.00 max	2.00 max
Standoff	0.05 min	0.05 min
Lead width	0.22–0.38	0.22–0.38
Foot length	0.55–0.95	0.55–0.95
Lead thickness	0.09–0.25	0.09–0.25
Lead angle	0°–8°	0°–8°
Coplanarity	not stated (0.1 datum C)	0.10

All values in millimeters, per the drawing revisions cited. The two drawings agree to the last digit, which is what compliance to a common registration is supposed to buy you. Mold flash is excluded and may add up to 0.15 mm per side on the TI part.

[IMAGE 1: dimensioned top and side view of the MO-150 SSOP-16 outline, with pitch, body, span and height called out | alt: “SSOP-16 package dimensions diagram showing 5.3 mm body width, 6.2 mm length and 7.8 mm lead span”]

SSOP-16 pinout: what the package does not define

An SSOP-16 pinout search usually means one of two things: which physical pin is number one, or what the pins of a specific device do. The package answers only the first.

Numbering runs counterclockwise from the pin 1 index mark, so pins 1 to 8 sit along the left edge in the top view and pins 9 to 16 return up the right edge. TI marks a pin 1 index area on DB0016A; on ADI drawings the marker is either a bevel edge or a dimple.

Function assignment belongs to the silicon. The SN74HC595 data sheet (SCLS041J) prints one pin table covering the D, DB, DW, J, N, NS and PW packages: VCC on 16, GND on 8, OE on 13, RCLK on 12, SRCLK on 11, SRCLR on 10, SER on 14, QA on 15 and QB–QH on 1–7. Package migration therefore changes the footprint and nothing in the schematic.

The migration risk is mechanical, not logical. SSOP-16 and SOP-16 in TI’s NS body share a 7.4–8.2 mm lead span, so a footprint that looks right at a glance can still be wrong by a factor of two in pitch.

[IMAGE 2: top view of a 16-lead SSOP with the pin 1 index area highlighted and counterclockwise numbering | alt: “SSOP-16 pinout top view with pin 1 index mark and counterclockwise numbering to pin 16”]

SSOP-16 footprint and land pattern

TI’s example board layout for DB0016A calls out 16 pads of 1.85 mm × 0.45 mm on 0.65 mm pitch with the two rows on 7.00 mm centers. That resolves to an 8.85 mm outer span, a 5.15 mm inner gap and a 5.00 mm pad-row length. Non-solder-mask-defined pads are marked as preferred.

Check the fillets against the package tolerances before you accept it. Heel span is lead span minus twice the foot length, so it runs 5.50 mm minimum to 7.10 mm maximum. Against the 8.85 mm outer land, a worst-case long part (8.2 mm span) still leaves 0.325 mm of toe fillet per side. Against the 5.50 mm minimum heel span, the 5.15 mm inner gap leaves 0.175 mm of heel. A 0.38 mm maximum lead on a 0.45 mm pad leaves 0.035 mm per side. Those are the numbers an assembly house inspects to IPC-A-610.

Table 3. Published lands for 16-lead small-outline packages, side by side

Source and package	Pitch (mm)	Pad (mm)	Row centers (mm)	Outer span (mm)	Inner gap (mm)
TI DB0016A, SSOP-16	0.65	1.85 × 0.45	7.00	8.85	5.15
Richtek, SSOP-16	0.635	1.30 × 0.30	5.50	6.80	4.20
TI NS0016A, SOP-16	1.27	1.85 × 0.60	7.00	8.85	5.15
TI PW0016A, TSSOP-16	0.65	1.50 × 0.45	5.80	7.30	4.30

Read the third row twice. TI’s SOP-16 land is dimensionally identical to its SSOP-16 land except for pad width and pitch, because both packages sit on the same 7.4–8.2 mm lead span. Copying a working SOP-16 footprint and editing the pitch is the single most common way to arrive at a board that reflows into a bridge farm.

For library work, the IPC-7351B name for the MO-150 part is built as SOP65P780X200-16N: 0.65 mm pitch, 7.80 mm nominal span, 2.00 mm height, 16 terminals, N for the nominal density level. Level M widens the fillets for hand-assembled or Class 3 work; level L tightens them for dense boards.

[INTERNAL LINK: IPC-7351 density levels -> PCB land pattern standards article]

[IMAGE 3: recommended SSOP-16 land pattern with pad size, pitch and row-center dimensions | alt: “SSOP-16 footprint with 1.85 by 0.45 mm pads on 0.65 mm pitch and 7.00 mm row centers”]

Stencil aperture at 1:1 on the 0.125 mm foil TI specifies deposits 1.85 × 0.45 × 0.125 = 0.104 mm³ of paste per pad, 1.67 mm³ for the part. Below about 0.08 mm³ per joint on a 0.65 mm pitch, expect heel voiding rather than open joints.

Tape, reel, moisture and reflow

The SN74HC595DBR ships 2,000 pieces on a 330 mm reel in 16 mm tape, cavity A0 8.35 mm, B0 6.6 mm, K0 2.4 mm, pitch P1 12.0 mm, pin 1 in quadrant Q1. The TSSOP version of the same die uses 12 mm tape on 8.0 mm pitch. Swapping package late in a build therefore means a feeder change, not a reel swap.

The DB parts carry an MSL rating of Level-1-260C-UNLIM with NIPDAU lead finish, so no bake and no floor-life clock at 260 °C peak reflow. Toshiba’s SSOP16-P-225-0.65B is also supplied in embossed tape at 2,000 pieces per reel. Confirm the level on the shipping label rather than the datasheet: dry-pack requirements travel with the lot, not the drawing.

[INTERNAL LINK: moisture sensitivity level handling -> SMT storage and bake-out article]

Thermal performance sits mid-pack

Because TI characterizes one die in six bodies, the SN74HC595 data sheet is a clean controlled comparison of package thermal resistance.

Table 4. Junction-to-ambient thermal resistance, same die, six packages

Package (TI suffix)	16-pin RθJA (°C/W)
SOIC wide, DW	57
SOP, NS	64
PDIP, N	67
SOIC narrow, D	73
SSOP, DB	82
TSSOP, PW	108

Values from SN74HC595 (SCLS041J, revised October 2021), JEDEC-standard board conditions. Toshiba quotes 94.7 °C/W for its narrower SSOP16-P-225-0.65B, which is the penalty for the smaller lead frame rather than a contradiction.

Work an example. A part dissipating 250 mW in an 85 °C ambient runs 20.5 °C above ambient in the DB body, so a junction at 105.5 °C against the 150 °C absolute maximum. The same die in TSSOP reaches 112 °C. On a 5 V rail that difference decides whether you need copper pour under the part.

When SSOP-16 is the right call

Choose MO-150 SSOP-16 when the board is length-constrained but has 2 mm of z-height: nominal body length is 6.20 mm against 9.90 mm for the narrow SOIC-16 carrying the same 16 pins, per the device information table in SCLS041J.
Choose TSSOP-16 when the stack-up caps component height near 1.2 mm, and accept 26 °C/W more thermal resistance.
Choose SOIC-16 when the part dissipates real power, when the line is Class 3 with manual rework, or when the design must survive a hand-populated prototype run.
Choose QSOP-16 (the 0.635 mm, 3.9 mm body outline) only if the part number you actually intend to buy is registered to MO-137. Do not treat it as a second source for an MO-150 part.
Whichever you choose, order the footprint from the drawing number in the datasheet’s mechanical section, not from the package name in the parametric table.

[INTERNAL LINK: TSSOP-16 package dimensions -> TSSOP reference article]

Five mistakes that scrap SSOP-16 boards

Pulling a generic “SSOP-16” library part with 0.635 mm pitch for an MO-150 device. Over 16 leads the accumulated error reaches 0.105 mm, and the outer pads miss entirely.
Inheriting a SOP-16 land and changing only the pitch, which leaves 0.60 mm pads on 0.65 mm centers: 0.05 mm of clearance and a bridging defect waiting for the next paste release.
Ordering the DB suffix and laying out for PW, or the reverse. The lead span differs by 1.6 mm and the height by 0.8 mm.
Ignoring the 2.0 mm maximum height in a shielded or stacked assembly where the clearance budget assumed a TSSOP.
Buying “SSOP-16” adapters or sockets by name. Adapter vendors list 0.635 mm, 4.4 mm and 5.3 mm bodies under that one label, so specify pitch and body width on the purchase order.

Frequently asked questions

What are the dimensions of an SSOP-16 package?

For the JEDEC MO-150 version, the body is 5.0 to 5.6 mm wide and 5.9 to 6.5 mm long, leads sit on 0.65 mm pitch, the tip-to-tip span is 7.4 to 8.2 mm and maximum seated height is 2.0 mm. Foot length runs 0.55 to 0.95 mm and lead width 0.22 to 0.38 mm.

Is SSOP-16 the same as TSSOP-16?

No. Both use 0.65 mm pitch, but TSSOP-16 under MO-153 is 4.3 to 4.5 mm wide with a 6.2 to 6.6 mm lead span and 1.2 mm maximum height, against 5.0 to 5.6 mm, 7.4 to 8.2 mm and 2.0 mm for SSOP-16. The land patterns are not interchangeable.

What is the SSOP-16 pin pitch?

Usually 0.65 mm. A second family, registered as MO-137 and normally called QSOP, uses 0.635 mm on a 3.9 mm body, and some vendors still label it SSOP-16. The 0.015 mm difference is harmless per lead and fatal across sixteen of them.

What footprint should I use for an SSOP-16?

Start from the vendor drawing. TI recommends 16 pads of 1.85 mm × 0.45 mm on 0.65 mm pitch with rows on 7.00 mm centers, non-solder-mask-defined. That is an 8.85 mm outer span. Verify against your own part: Richtek publishes 6.80 mm for its SSOP-16.

Can you hand-solder an SSOP-16?

Yes. At 0.65 mm pitch, drag soldering with flux and wick is routine for an experienced technician, and the 2.0 mm body gives more thermal mass than a TSSOP. Design the land with the IPC-7351 M density level if hand assembly or rework is expected.

How many parts fit on an SSOP-16 reel?

Two thousand is the standard quantity for both TI and Toshiba 16-lead SSOP devices. TI ships them on a 330 mm reel in 16 mm embossed tape with 12 mm cavity pitch, so a feeder set up for 12 mm TSSOP tape will not take the reel.

What to do next

Open the mechanical section of the datasheet for the exact orderable part number and read the drawing number, not the package name. If it references MO-150, build the 8.85 mm land and budget 2.0 mm of height. If it references MO-137 or shows 0.635 mm pitch, build a separate library part and name it QSOP so nobody reuses it by accident. If the drawing shows 0.65 mm pitch on a 4.4 mm body, you are holding a TSSOP whatever the marketing name says.

For a new design with no legacy constraint, specify TSSOP-16 for height-limited digital work and SOIC-16 wherever power or rework matters. SSOP-16 earns its place in the middle: shorter than SOIC, sturdier than TSSOP, and available in high-runner logic such as the SN74HC595DBR at 2,000 pieces per reel.

Sources

Texas Instruments, SN54HC595 / SN74HC595 data sheet SCLS041J: https://www.ti.com/lit/ds/symlink/sn74hc595.pdf
Analog Devices, 16-lead SSOP (RS-16) package drawing: https://www.analog.com/media/en/package-pcb-resources/package/31572257652246rs_16.pdf
Analog Devices / Linear Technology, GN16 16-lead SSOP (narrow 0.150 inch) drawing: https://www.analog.com/media/en/package-pcb-resources/package/pkg_pdf/ltc-legacy-ssop/05081641_b_gn16.pdf
Richtek, SSOP-16 recommended footprint: https://www.richtek.com/assets/podfiles/Footprint-SSOP-16.pdf
Toshiba, SSOP16-P-225-0.65B package and packing data: https://toshiba.semicon-storage.com/us/semiconductor/design-development/package/detail.SSOP16-P-225-0.65B.html
JEDEC, JEP95 outline index (MO-150, MO-137, MO-153 titles): https://www.jedec.org/sites/default/files/Main.pdf