Smart Highside High Current Power Switch

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1 Smart Highside High Current Power Switch Features Overload protection Current limitation Short circuit protection Overtemperature protection Overvoltage protection (including load dump) Clamp of negative voltage at output Fast deenergizing of inductive loads 1) Low ohmic inverse current operation Reverse battery protection Diagnostic feedback with load current sense Open load detection via current sense Loss of bb protection 2) Electrostatic discharge (ESD) protection Product Summary Overvoltage protection bb(az) 62 Output clamp ON(CL) 42 Operating voltage bb(on) On-state resistance RON 2.9 mω Load current (O) IL(O) 158 A Short circuit current limitation IL(SCp) 4 A Current sense ratio IL : I 3 TO-218AB/5 Application Power switch with current sense diagnostic feedback for 12 and 24 DC grounded loads Most suitable for loads with high inrush current like lamps and motors; all types of resistive and inductive loads Replaces electromechanical relays, fuses and discrete circuits 1 Straight leads 5 General Description N channel vertical power FET with charge pump, current controlled input and diagnostic feedback with load current sense, integrated in Smart SIPMOS chip on chip technology. Fully protected by embedded protection functions. 3 & Tab + bb oltage source Overvoltage protection Current limit Gate protection R bb 2 ESD oltage sensor Logic Charge pump Level shifter Rectifier Limit for unclamped ind. loads Output oltage detection Current Sense 1, 5 I L Load I Temperature sensor I 4 Load GND R Logic GND 1 ) With additional external diode. 2) Additional external diode required for energized inductive loads (see page 8). Semiconductor Group Page 1 of Dec-21

2 Pin Symbol Function 1 O Output to the load. The pins 1 and 5 must be shorted with each other especially in high current applications! 3) 2 I Input, activates the power switch in case of short to ground 3 bb + 4 S 5 O Positive power supply voltage, the tab is electrically connected to this pin. In high current applications the tab should be used for the bb connection instead of this pin 4). Diagnostic feedback providing a sense current proportional to the load current; zero current on failure (see Truth Table on page 6) Output to the load. The pins 1 and 5 must be shorted with each other especially in high current applications! 3) Maximum Ratings at Tj = 25 C unless otherwise specified Parameter Symbol alues Unit Supply voltage (overvoltage protection see page 4) bb 42 Supply voltage for full short circuit protection with bb 34 resistive load, for L see diagram on page 9 T j,start = C: Load current (short circuit current, see page 4) I L self-limited A Load dump protection LoadDump = U A + s, U A = ) R I = 2 Ω, R L =.1 Ω, t d = 2 ms, 6) Load dump 8, = open or grounded Operating temperature range T j C Storage temperature range T stg Power dissipation (DC), T C 25 C P tot 31 W Inductive load switch-off energy dissipation, single pulse bb = 12, T j,start = 15 C, T C = 15 C const., E AS 3 J I L = 2 A, Z L = 15 mh, Ω, see diagrams on page 9 Electrostatic discharge capability (ESD) ESD 4. k Human Body Model acc. MIL-STD883D, method and ESD assn. std. S , C = 1 pf, R = 1.5 kω Current through input pin (DC) Current through current sense status pin (DC) see internal circuit diagrams on page 7 I I +15, , -25 ma 3) Not shorting all outputs will considerably increase the on-state resistance, reduce the peak current capability and decrease the current sense accuracy 4) Otherwise add up to.5 mω (depending on used length of the pin) to the R ON if the pin is used instead of the tab. 5) R I = internal resistance of the load dump test pulse generator. 6) Load dump is setup without the DUT connected to the generator per O and D Semiconductor Group Page Dec-21

3 Thermal Characteristics Parameter and Conditions Symbol alues Unit min typ max Thermal resistance chip - case: R thjc 7).4 K/W junction - ambient (free air): R thja 3 Electrical Characteristics Parameter and Conditions Symbol alues Unit at Tj = C, bb = 12 unless otherwise specified min typ max Load Switching Capabilities and Characteristics On-state resistance (Tab to pins 1,5, see measurement circuit page 7) I L = 3 A, T j = 25 C: =, I L = 3 A, T j = 15 C: R ON I L = 18 A, T j = 15 C: 5. bb = 6 8), I L = 2 A, T j = 15 C: R ON(Static) Nominal load current 9) (Tab to pins 1,5) I L(O) A O /6.7: ON =.5, Tc = 85 C 1) Maximum load current in resistive range (Tab to pins 1,5) ON = 1.8, Tc = 25 C: see diagram on page 12 ON = 1.8, Tc = 15 C: Turn-on time 11) I to 9% : Turn-off time I to 1% : R L = 1 Ω, T j = C Slew rate on 11) (1 to 3% ) R L = 1 Ω Slew rate off 11) (7 to 4% ) R L = 1 Ω I L(Max) 45 3 t on 12 t off 5 mω A 6 µs 24 d/dt on.8 /µs -d/dt off.8 /µs Inverse Load Current Operation On-state resistance (Pins 1,5 to pin 3) b = 12, I L = - 3 A T j = 25 C: R ON(inv) mω see diagram on page 9 T j = 15 C: Nominal inverse load current (Pins 1,5 to Tab) I L(inv) A ON = -.5, Tc = 85 C 1 Drain-source diode voltage (out > bb) I L = - 2 A, I =, Tj = +15 C - ON.6 7) Thermal resistance R thch case to heatsink (about.25 K/W with silicone paste) not included! 8) Decrease of bb below 1 causes slowly a dynamic increase of R ON to a higher value of R ON(Static). As long as b > b(u) max, R ON increase is less than 1 % per second for T J < 85 C. 9) Not tested, specified by design. 1) T J is about 15 C under these conditions. 11) See timing diagram on page 13. Semiconductor Group Page Dec-21

4 Parameter and Conditions Symbol alues Unit at Tj = C, bb = 12 unless otherwise specified min typ max Operating Parameters Operating voltage ( = ) 12) bb(on) Undervoltage shutdown 13) b(u) Undervoltage start of charge pump see diagram page 14 b(ucp) Overvoltage protection 14) T j =-4 C: b(z) 6 I bb = 15 ma T j = C: Standby current T j = C: I bb(off) µa I = T j = 15 C: 25 6 Protection Functions Short circuit current limit (Tab to pins 1,5) ON = 12, time until shutdown max. 3 µs T c =-4 C: T c =25 C: T c =+15 C: Short circuit shutdown delay after input current positive slope, ON > ON(SC) min. value valid only if input "off-signal" time exceeds 3 µs Output clamp 15) I L = 4 ma: (inductive load switch off) Output clamp (inductive load switch off) at = bb - ON(CL) (e.g. overvoltage) I L = 4 ma I L(SCp) t d(sc) 8 3 µs - (CL) ON(CL) Short circuit shutdown detection voltage (pin 3 to pins 1,5) ON(SC) 6 A 12) If the device is turned on before a bb -decrease, the operating voltage range is extended down to b(u). For the voltage range..34 the device is fully protected against overtemperature and short circuit. 13) b = bb - see diagram on page 7. When b increases from less than b(u) up to b(ucp) = 5 (typ.) the charge pump is not active and bb ) See also ON(CL) in circuit diagram on page 8. 15) This output clamp can be "switched off" by using an additional diode at the -Pin (see page 7). If the diode is used, is clamped to bb - ON(CL) at inductive load switch off. Semiconductor Group Page Dec-21

5 Parameter and Conditions Symbol alues Unit at Tj = C, bb = 12 unless otherwise specified min typ max Thermal overload trip temperature T jt 15 C Thermal hysteresis T jt 1 K Reverse Battery Reverse battery voltage 16) - bb 16 On-state resistance (Pins 1,5 to pin 3) T j = 25 C: R ON(rev) bb = -12, =, I L = - 3 A, R = 1 kω T j = 15 C: mω Integrated resistor in bb line R bb 12 Ω Diagnostic Characteristics Current sense ratio, static on-condition, k IL = I L : I, ON < ), < - 5 v, b > 4. see diagram on 11 I L = 18 A,T j =-4 C: T j =25 C: T j =15 C: I L = 3 A,T j =-4 C: T j =25 C: T j =15 C: I L = 16 A,T j =-4 C: T j =25 C: T j =15 C: I L = 8 A,T j =-4 C: T j =25 C: T j =15 C: k IL I = by I = (e.g. during deenergizing of inductive loads): Sense current saturation I,lim 6.5 ma Current sense leakage current I =, = : =, =, I L : I (LL) I (LH) 2.5 µa Current sense settling time 18) t s() 5 µs Overvoltage protection I bb = 15 ma T j =-4 C: T j = C: b(z) ) The reverse load current through the intrinsic drain-source diode has to be limited by the connected load (as it is done with all polarity symmetric loads). Note that under off-conditions (I = I = ) the power transistor is not activated. This results in raised power dissipation due to the higher voltage drop across the intrinsic drain-source diode. The temperature protection is not active during reverse current operation! Increasing reverse battery voltage capability is simply possible as described on page 8. 17) If ON is higher, the sense current is no longer proportional to the load current due to sense current saturation, see I,lim. 18) Not tested, specified by design. Semiconductor Group Page Dec-21

6 Parameter and Conditions Symbol alues Unit at Tj = C, bb = 12 unless otherwise specified min typ max Input Input and operating current (see diagram page 12) I (on) ma grounded ( = ) Input current for turn-off 19) I (off) 4 µa Truth Table Normal operation ery high load current Currentlimitation Short circuit to GND Overtemperature Short circuit to bb Open load Negative output voltage clamp Inverse load current Input current Output Current Sense level level I L H L H nominal Remark =I L / k ilis, up to I =I,lim up to H H I ON = ON(Fold back), lim I no longer proportional to I L H H ON > ON(Fold back) if ON > ON(SC), shutdown will occure L L H L L L H L L H H H <nominal 2) L Z 21 ) H H L L L H H H L = "Low" Level H = "High" Level Overtemperature reset via input: I =low and Tj < Tjt (see diagram on page14) Short circuit to GND: Shutdown remains latched until next reset via input (see diagram on page 13) 19) We recommend the resistance between and GND to be less than.5 kω for turn-on and more than 5kΩ for turn-off. Consider that when the device is switched off (I = ) the voltage between and GND reaches almost bb. 2) Low ohmic short to bb may reduce the output current I L and can thus be detected via the sense current I. 21) Power Transistor "OFF", potential defined by external impedance. Semiconductor Group Page Dec-21

7 Terms bb b R I 2 b 3 bb 4 I bb I D S R I L 1,5 Two or more devices can easily be connected in parallel to increase load current capability. R ON measurement layout 5.5 mm ON Current sense status output bb R bb I ZD Z, R Z, = 66 (typ.), R = 1 kω nominal (or 1 kω /n, if n devices are connected in parallel). I S = I L /k ilis can be only driven by the internal circuit as long as out - > 5. If you want to measure load currents up to I L(M), R should be less than bb 5. I L ( M ) / K ilis Note: For large values of R the voltage can reach almost bb. See also overvoltage protection. If you don t use the current sense output in your application, you can leave it open. Short circuit detection Fault Condition: ON > ON(SC) (6 typ.) and t> t d(sc) (8...3 µs). bb force contacts Out Force contacts (both out pins parallel) Sense contacts + bb ON Input circuit (ESD protection) bb Logic unit Short circuit detection Z, ZD R bb Inductive and overvoltage output clamp + bb b Z1 I ON ZG When the device is switched off (I = ) the voltage between and GND reaches almost bb. Use a mechanical switch, a bipolar or MOS transistor with appropriate breakdown voltage as driver. Z, = 66 (typ). D S ON is clamped to ON(Cl) = 42 typ. At inductive load switch-off without D S, is clamped to (CL) = -17 typ. via ZG. With D S, is clamped to bb - ON(CL) via Z1. Using D S gives faster deenergizing of Semiconductor Group Page Dec-21

8 the inductive load, but higher peak power dissipation in the. Overvoltage protection of logic part R Z, Z, Logic R bb + bb bb disconnect with energized inductive load Provide a current path with load current capability by using a diode, a Z-diode, or a varistor. ( ZL < 72 or Zb < 3 if R =). For higher clamp voltages currents at and have to be limited to 25 ma. ersion a: bb bb R R Z, Signal GND R bb = 12 Ω typ., Z, = Z, = 66 typ., R = 1 kω nominal. Note that when overvoltage exceeds 71 typ. a voltage above 5 can occur between and GND, if R, Z, are not used. Reverse battery protection ersion b: ZL - bb bb bb R bb R Logic Power Transistor Zb D Signal GND D S R R R L Power GND R 1 kω, R = 1 kω nominal. Add R for reverse battery protection in applications with bb above 16 16) ; recommended value: = R R R.1A bb - 12 if D S is not used (or 1.1A = R bb - 12 if D S is used). To minimize power dissipation at reverse battery operation, the summarized current into the and pin should be about 12mA. The current can be provided by using a small signal diode D in parallel to the input switch, by using a MOSFET input switch or by proper adjusting the current through R and R. Note that there is no reverse battery protection when using a diode without additional Z-diode ZL, Zb. ersion c: Sometimes a neccessary voltage clamp is given by non inductive loads R L connected to the same switch and eliminates the need of clamping circuit: bb bb R L Semiconductor Group Page Dec-21

9 Inverse load current operation bb bb + - I L Maximum allowable load inductance for a single switch off L = f (I L ); T j,start = 15 C, bb = 12, R L = Ω L [µh] I R The device is specified for inverse load current operation ( > bb > ). The current sense feature is not available during this kind of operation (I = ). With I = (e.g. input open) only the intrinsic drain source diode is conducting resulting in considerably increased power dissipation. If the device is switched on ( = ), this power dissipation is decreased to the much lower value R ON() * I 2 (specifications see page 3). Note: Temperature protection during inverse load current operation is not possible! Inductive load switch-off energy dissipation E bb E AS I L [A] Externally adjustable current limit bb I bb R i (t) L L Z L { R L E Load E L E R If the device is conducting, the sense current can be used to reduce the short circuit current and allow higher lead inductance (see diagram above). The device will be turned off, if the threshold voltage of T2 is reached by I S *R. After a delay time defined by R *C T1 will be reset. The device is turned on again, the short circuit current is defined by I L(SC) and the device is shut down after t d(sc) with latch function. Energy stored in load inductance: bb E L = 1 /2 L I 2 L bb While demagnetizing load inductance, the energy dissipated in is E AS = E bb + E L - E R = ON(CL) i L (t) dt, R with an approximate solution for R L > Ω: E AS = IL L IL RL ( 2 R bb + (CL) ) ln (1+ L (CL) ) Signal Signal GND T1 C T2 R R load Power GND Semiconductor Group Page Dec-21

10 Options Overview Type BTS 55P 65P Overtemperature protection with hysteresis X X Tj >15 C, latch function 22) X Tj >15 C, with auto-restart on cooling X Short circuit to GND protection switches off when ON >6 typ. X X (when first turned on after approx. 18 µs) Overvoltage shutdown - - Output negative voltage transient limit to bb - ON(CL) X X to = -15 typ X 23) X 23) 22) Latch except when bb - < ON(SC) after shutdown. In most cases = after shutdown ( only if forced externally). So the device remains latched unless bb < ON(SC) (see page 4). No latch between turn on and t d(sc). 23) Can be "switched off" by using a diode DS (see page 7) or leaving open the current sense output. Semiconductor Group Page Dec-21

11 Characteristics Current sense versus load current: I = f(i L ) I [ma] Current sense ratio: K IL = f(i L ), T J = 25 C k ilis max min 4 35 max 2 3 typ min I L [A] I L [A] Current sense ratio: K IL = f(i L ), T J = -4 C k ilis Current sense ratio: K IL = f(i L ), T J = 15 C k ilis max typ 35 3 max 25 2 min typ min I L [A] I L [A] Semiconductor Group Page Dec-21

12 Typ. current limitation characteristic I L = f (ON, T j ) I L [A] 1 Typ. input current I = f ( b ), b = bb - I [ma] ON > ON(SC) only for t < t d(sc) (otherwise immediate shutdown) T j = -4 C 25 C 85 C 15 C ON(FB) ON [] In case of ON > ON(SC) (typ. 6 ) the device will be switched off by internal short circuit detection. Typ. on-state resistance R ON = f ( bb, T j ); I L = 3 A; = R ON [mohm] b [] 5 static dynamic T j = 15 C 85 C 25 C -4 C bb [] Semiconductor Group Page Dec-21

13 Timing diagrams Figure 1a: Switching a resistive load, change of load current in on-condition: Figure 2b: Switching an inductive load: I I d/dtoff 9% t on 1% d/dton t off I L tslc() tslc() I L Load 1 Load 2 I t son() t soff() t I t The sense signal is not valid during a settling time after turn-on/off and after change of load current. Figure 2a: Switching motors and lamps: Figure 3a: Short circuit: shut down by short circuit detection, reset by I =. I I I L I L(SCp) t d(sc) I IL I >> = t I Sense current saturation can occur at very high inrush currents (see I,lim on page 5). t Shut down remains latched until next reset via input. Semiconductor Group Page Dec-21

14 Figure 4a: Overtemperature, Reset if (I =low) and (T j <T jt ) I I S T J t Figure 6a: Undervoltage restart of charge pump, overvoltage clamp = 6 4 dynamic, short Undervoltage not below b(u) ON(CL) 2 I = ON(CL) b(u) b(ucp) Semiconductor Group Page Dec-21

15 Package and Ordering Code All dimensions in mm TO-218AB/5 Option E3146 Ordering code BTS555 E3146 Q676-S6953A3 Published by Siemens AG, Bereich Halbleiter etrieb, Werbung, Balanstraße 73, D München Siemens AG All Rights Reserved Attention please! As far as patents or other rights of third parties are concerned, liability is only assumed for components, not for applications, processes and circuits implemented within components or assemblies. The information describes a type of component and shall not be considered as warranted characteristics. Terms of delivery and rights to change design reserved. For questions on technology, delivery and prices please contact the Semiconductor Group Offices in Germany or the Siemens Companies and Representatives worldwide (see address list). Due to technical requirements components may contain dangerous substances. For information on the types in question please contact your nearest Siemens Office, Semiconductor Group. Siemens AG is an approved CECC manufacturer. Packing: Please use the recycling operators known to you. We can also help you - get in touch with your nearest sales office. By agreement we will take packing material back, if it is sorted. You must bear the costs of transport. For packing material that is returned to us unsorted or which we are not obliged to accept, we shall have to invoice you for any costs incurred. Components used in life-support devices or systems must be expressly authorised for such purpose! Critical components 24) of the Semiconductor Group of Siemens AG, may only be used in life supporting devices or systems 25) with the express written approval of the Semiconductor Group of Siemens AG. 24) A critical component is a component used in a life-support device or system whose failure can reasonably be expected to cause the failure of that life-support device or system, or to affect its safety or effectiveness of that device or system. 25) Life support devices or systems are intended (a) to be implanted in the human body or (b) support and/or maintain and sustain and/or protect human life. If they fail, it is reasonably to assume that the health of the user or other persons may be endangered. Semiconductor Group Page Dec-21

Smart Highside High Current Power Switch

Smart Highside High Current Power Switch Reversave Reverse battery protection by self turn on of power MOSFET Features Overload protection Current limitation Short circuit protection Over temperature protection