20-Position Bottom-Contact ZIF at 0.50mm Pitch
The 20FLZ-RSM2-TB(LF)(SN) is a 20-position, 0.50mm pitch FFC/FPC connector from JST's FLZ series, using a bottom-contact ZIF design with a slide lock actuator. The bottom-contact arrangement means the FPC's conductive pads face down against the PCB, so the cable inserts with the exposed traces downward; mixing up the orientation shorts the circuit. Rated 0.5A per contact at 50V, with an operating range of -25°C to 85°C. The 0.5A ceiling is typical for 0.50mm-pitch signal connectors — the narrow contact beam and fine pitch limit current per circuit well before the housing material (UL94 V-0 polyamide) reaches its thermal limit. The -25°C to 85°C span covers most consumer, commercial, and indoor industrial gear; outdoor or engine-compartment applications need a wider-range part.
ZIF Actuator and Slide Lock — What They Do for the Fit
The zero-insertion-force (ZIF) mechanism means the FPC slides in freely with the actuator open, then the slide lock clamps the contacts against the cable pads. No insertion force on the cable — the risk of tearing the thin 0.30mm FPC foil is eliminated. The slide lock also provides positive retention: once closed, it holds the cable against vibration and handling without a secondary latch. Without them, the ZIF actuation force can shift the part on the solder paste before reflow.
Tin Plating — When It Works, When It Doesn't
The contacts are tin-plated phosphor bronze. Below about 20 cycles the tin oxide film breaks in reliably; above 50 cycles the oxide builds up and contact resistance drifts. For high-cycle or corrosive environments (field-service, outdoor panels), a gold-plated sibling would be the better call — but this part keeps the BOM cost down for consumer or single-mate assembly.
RoHS compliant.
How It Sits Against the FLZ Siblings
The FLZ series includes three 20-position variants at the same 0.50mm pitch and 2.00mm height: the 20FLZ-RSM2-TB (natural housing, bottom contact), the 20FLZ-SM2-TB (gray housing, top contact), and the 20FLZ-SM2-TB(LF)(SN) (gray housing, top contact, RoHS). The only difference between the bottom-contact and top-contact versions is which side of the FPC the contacts wipe — bottom-contact means the cable's conductive traces face the PCB; top-contact means they face away. Choose the variant that matches your FPC pad orientation and the board layout. The tin plating and 0.5A rating are identical across all three.