SY2640 / SY2642 64-Ch HV Switch: BGA vs LGA Path

When probe or array channel count moves from 32 to 64, the hard part is rarely “finding a 64-channel part.” It is usually whether the package can pass production, whether logic levels match the FPGA, and whether MUX topology plus bleed/noise budget still close. Synergy’s 64-channel pair is already in volume and shares a +5V control-side approach for 2:1 / 1:2 MUX use:

• SY2640: 64-channel HV analog switch (family table: 2:1 MUX), BGA120 (10.0×10.0mm, 0.80mm pitch), roughly 3V–5V CMOS logic
• SY2642: 64-channel 1:2 MUX, LGA110 (14.5×10.0mm, 0.40mm pitch), roughly 1.8V–5V CMOS logic

Public notes for both align on ~0V to ±100V analog range, integrated ~40kΩ bleed resistors, ~50MHz shift clock, low charge injection, and off-isolation / crosstalk on the order of -57dB / -60dB (confirm in datasheets). Unlike the 16/32-channel split between legacy HV rails and +5V control, this 64-channel pair mainly splits on package and logic voltage.

When does 64 channels make sense?

If SY216x / SY232x already prove the TX–switch path and you simply need density, evaluate a single 64-channel device before stacking multiple 32-channel switches in the same thermal zone. Typical cases: denser medical ultrasound probes, multi-channel / phased-array NDT, piezoelectric arrays, and layouts that must keep the HV matrix near the probe or inside a tight host board.

Keep the pulser budget in the same plan (for example SY5817 arrays). Pulsers and HV switches are upstream/downstream partners, not substitutes. Scan the family cross-reference first, then use this page for the 64-channel shortlist.

Same 64-ch +5V class: SY2640 vs SY2642

If your board is already BGA-ready, reflow/X-ray capable, and logic stays at 3.3V / 5V, start with SY2640.
If you prefer LGA assembly, need 1.8V logic headroom, or want the materials that emphasize 1:2 MUX wording, prioritize SY2642.

The family table lists both in the 2:1 MUX class; the SY2642 product page stresses 1:2 MUX. Use the latest datasheet topology drawing—do not swap part numbers by channel count alone.

Note: Cross-references help shortlisting; they are not drop-in guarantees. Validate voltage rating, Ron, charge injection, timing, bleed, and layout/creepage before production.

Seven questions for a 64-ch shortlist

1. Do you truly need a single 64-channel device, or will multi-device 32-ch stacking create worse thermal and skew issues?
2. Is topology confirmed as 2:1 / 1:2 MUX? If you need SPST, return to SY2325 / SY2326 or redesign channel architecture.
3. Is control planned around +5V single supply? Do not reuse assumptions from HV-rail 16/32-ch parts.
4. Is the FPGA / sequencer at 1.8V or 3.3V / 5V? That often decides SY2642 vs SY2640 first.
5. Which process is more mature: BGA120 or LGA110? Can you support 0.80mm vs 0.40mm pitch, reflow, and inspection?
6. Do bleed resistors, off-isolation, and crosstalk meet the receive noise budget? Can the RX front end absorb charge injection?
7. Have transmit peaks, probe capacitive load, and thermal strategy been co-validated with the pulser array?

How this fits 16/32-ch and front-end pairing

For fewer channels:

• SY2160 / SY2162 16-ch guide
• SY2320 / SY2322 32-ch MUX guide

For pulser + switch pairing, read: Ultrasound front-end: pulser + HV switch pairing. Full family matrix: Synergy HV analog switch alternative overview.

Datasheets and inquiry

SY2640 product page / datasheet · SY2642 product page / datasheet

Jarwey can help with selection guidance, application support, sampling / small batch, and lead-time coordination. Share channel count, logic voltage, and package constraints for a faster 64-channel shortlist.

Contact: kerry.w@jarwey.cn · Contact Jarwey

Summary

Do not pick a 64-channel HV switch by channel count alone. Confirm you need a dense single-chip MUX, then split SY2640 vs SY2642 by package (BGA120 vs LGA110) and logic voltage (3V–5V vs 1.8V–5V), and co-validate with the pulser array. Datasheet entry points are on the Jarwey product pages for pilot builds and RFQs.