FM712 For extended common-mode RS-485 Applications Protection of RS-485 transceivers with extended common– mode range ● Security systems ● Automatic Teller Machines ● HFC systems ● Networks ● SOT-23 Feature 400 watts peak pulse power(tp=8/20us) ESD Protection:Level 4 ● Low clamping voltage ● Protects two +12v to –7v lines ● ● IEC Compatibility EN61000-4 ● 61000-4-2(ESD):Level4,Contact:±8kv,Air::±15kv ● 61000-4-4(EFT):40A-5/50ns ● 61000-4-5(Surge):12A,8/20us ● Mechanical Characteristics Molded JEDEC Sot-23 The Futurewafer® device will meet IEC61000-4-2(ESD) ● Flammability rating UL 94V-0 ● Halogen Free ● ● Device Characteristics Maximum Ratings@25 unless otherwise specified Parameter Peak pulse power (tp=8/20us) see fig 1. Operating Temperature Storage Temperature Symbol Value Units PPP 400 Watts TJ -55 ~150 °C TSTG -55 ~150 °C ③ Pin Identification 1,2 Input lines 3 Ground ① ② E1506F3C-STD-FW-003 Futurewafer Tech Co., Ltd FM712 For extended common-mode RS-485 Electrical Characteristics Pin 1 to 3 and 2 to 3 (12V TVS) Pin 3 to 1 and 3 to 2 (7V TVS) Units Parameter Symbol Condition VRWM Pin 3 to 1 or pin 2 to 1 VBR IZ=1mA Reverse Leakage Current IR VR=VRWM Forward Voltage VF IF=15mA Clamping Voltage VC Reverse Stand-off Voltage Reverse Breakdown Voltage Junction Capacitance C I/O-I/O Min. Typ. Max. Min. 12 13.3 Typ. Max. 7 7.5 1 V V 20 uA 1.15 V V pf IPP=5A 20 IPP=17A, 26 10 12 Vdc=0V, f=1MHZ 75 75 Rating and characteristic curve Figure 1 Non-repetitive peak pulse power vs. pulse time E1506F3C-STD-FW-003 Futurewafer Tech Co., Ltd FM712 For extended common-mode RS-485 Figure 3 Power derating Curve Figure 4 Capacitance vs.Reverse voltage Applications information Device connection for protectoion of two RS485 data lines EIA RS-485 specifies a +-7v ground difference between devices on the bus.This permits the bus voltage to range from +12v to -7v. The FM712 is designed to protect two RS485 data line in extended common mode applications. The FM712 may be used to protect devices from transient voltage resulting from ESD,EFT,and lightning. The device is designed with asymmetrical operating voltages for optimum protection. The tvs diodes at pins 1 and 2 have a working voltage of 12 volts.These pins are connected to the differential data line pairs. The tvs diodes at pin 3 have a working voltage of 7 volts. Pin 3 is connected to ground. The internal tvs diodes of the FM712 will protect the transceiver input from positive transient voltage spikes greater than 12v and negative spikes greater than 7v. A series current limiting resistor may be added in applications requiring enhanced surge immunity. E1506F3C-STD-FW-003 Futurewafer Tech Co., Ltd FM712 For extended common-mode RS-485 Tape&Reel information E1506F3C-STD-FW-003 Futurewafer Tech Co., Ltd FM712 For extended common-mode RS-485 Package information Mounting pad Ordering information Part No FM712 Marking Code 712 Packing 7” Reel/3,000pcs Futurewafer Technology Co., Ltd 台灣未來芯航電股份有限公司 Tel ：+886-3-3573583/Tel ：+886-3-3574065 Futurewafer.com.tw 桃園市桃園區中正路 987 巷 50 弄 2 號 E1506F3C-STD-FW-003 Futurewafer Tech Co., Ltd