Synergy Tier-1 distributor Jarwey｜Ultrasound HV switch thermal flag: SY2162QF threshold vs SY2326 pin 63 and SY2640 F3
Jarwey is a Synergy (Xinlijie) Tier-1 distributor and can help with selection, datasheets, samples, small lots, and lead time.
A line that says “thermal protection” on an ultrasound HV analog switch does not mean the FPGA has a pin to watch. SY2162QF publishes a junction threshold and no THP ball. SY2326 brings an open-drain flag out on pin 63. SY2640 puts the same class of flag on BGA ball F3, and the datasheet says Low means the flag is active. That split is the whole note.
This is not a rerun of the 16-channel SY2160 / SY2162 selection or the SY2640 versus SY2642 package split. Figures come from the public PDFs, including preliminary and Rev 0.x copies. Lock the BOM to the current PDF from Jarwey and to a measurement in the probe housing.
Threshold only, or a flag pin
| Part | Channels | What the thermal section says | External flag | Page |
|---|---|---|---|---|
| SY2162QF | 16, 48-LQFP | Yes. Threshold min 90°C / typ 110°C / max 130°C, hysteresis typ 10°C. Conditions: VDD=5 V, LEB=0, TA=25°C. No open-drain voltage row in that section | No THP in the 48-pin list. Do not pull up a pin that is not there | 853 |
| SY2326 | 32 SPST, 84-QFN | Same window: 90 / 110 / 130°C, hysteresis typ 10°C, at VLL=3.3 V, VDD=5 V, LEB=0, TA=25°C | Pin 63, open-drain N-MOS. VOL max 0.5 V when active at 1 mA, VLL=3.3 V. Pull-up max 5.25 V | 860 |
| SY2325 | 32 SPST, 84-LGA | Same thermal-protection rows as SY2326 | Pin 63, open-drain N-MOS | 859 |
| SY2322 | 32-ch 1:2, 64-QFN | Same threshold and hysteresis, plus open-drain electrical rows | Pin 46, open-drain N-MOS flag | 858 |
| SY2640 | 64, 120-BGA | Same threshold and hysteresis | Ball F3. Datasheet: Low = THP activating, open-drain N-MOS | 857 |
| SY2160 | 16, needs VPP/VNN | This PDF has no thermal-protection section | No THP. The 1.0 W absolute-max dissipation of the 48-LQFP is not a shutdown point | 856 |
| SY2320FN | 32, needs VPP/VNN | This PDF has no thermal-protection section | No THP. The 1.5 W absolute-max dissipation of the 64-LGA is not a shutdown point | 855 |
| SY2642 | 64-ch 1:2, 110-LGA | This PDF does not mention THP or thermal protection | No THP ball. A 64-channel label is not a reason to copy the SY2640 flag net | 861 |
How to use the 110°C typical point
- The window is wide. The threshold is allowed up to 130°C and down to 90°C. A probe-housing limit in the tens of degrees is a separate budget. Waiting for THP does not prove the case is inside that budget.
- Hysteresis is typ 10°C. The flag releases about 10°C below the trip, as a typical. Leave recovery time if firmware latches the alarm. Do not treat typ as a guaranteed per-unit number.
- Absolute maximum junction temperature is a different row. Parts that publish the thermal section list operating junction temperature up to about +150°C. The 110°C typical trip sits below that rating. It is not a case temperature, and it is not permission to run every channel at peak current.
- Pull up only a real open-drain pin. That is SY2322 pin 46, SY2325 / SY2326 pin 63, and SY2640 ball F3, with a pull-up at or below the 5.25 V maximum. SY2162QF has no such pin.
Selection checklist
- Find the pin before you write “thermal flag” on the schematic. If the pin list has no THP, treat the part as threshold-only. Firmware must not wait for a low that will never arrive.
- Polarity. SY2640 states Low = active. SY2322, SY2325, and SY2326 specify VOL while the flag is active. Wire them as open-drain, active low, pulled up on the VLL side. Do not tie the flag to VPP.
- Same channel count is not the same net. SY2640 has F3. This SY2642 PDF does not. SY2162QF has a threshold. This SY2160 PDF has no thermal section at all.
- A dissipation ceiling is not a trip point. 1.0 W on SY2160 and 1.5 W on SY2320FN sit in the absolute-maximum table. Switch loss and housing thermal resistance still belong on the board calculation.
- Thermal pad. The SY2322 and SY2325 package notes require the bottom pad to be soldered to ground. A floating pad moves the junction toward 110°C and changes what the flag means.
- Second source. If the incumbent is a Microchip, Hitachi, or Maxim HV switch, compare thermal-flag pins, threshold windows, and package balls on the two datasheets. Board validation is required. This is not a drop-in replacement.
- Datasheet. These PDFs are mostly preliminary or Rev 0.x. If the product-page download fails, ask Jarwey for the current datasheet, samples, and a small-lot date.
Datasheet and contact
- SY2326 32-channel SPST (THP on pin 63)
- SY2640 64-channel (F3 = THP)
- SY2162QF 16-channel (threshold, no THP pin)
Send the incumbent HV-switch part number, the allowed probe-housing temperature, and the logic rail to Jarwey. We can check the current PDF, the flag pin, and sample lead time. Measure at the target case temperature before a production swap.
Jarwey · Synergy Tier-1 distributor · kerry.w@jarwey.cn · Contact.
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