BTS3256D

HITFET™ Smart Low Side Power Switch BTS3256D 10 mΩ smart power single channel low side switch with restart and variable slew rate Datasheet Rev. 1.0, 2009-05-05 Automotive Smart Low Side Power Switch HITFET - BTS 3256D Table of Contents Table of Contents Table of Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 1 2 2.1 3 3.1 3.2 4 4.1 4.2 4.3 5 5.1 5.1.1 5.2 5.3 6 6.1 6.2 6.3 6.4 7 7.1 7.2 7.3 8 8.1 8.2 8.3 8.4 9 9.1 9.2 10 11 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 BTS 3256D Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Voltage and current naming definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Pin Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Pin Assignment BTS 3256D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Pin Definitions and Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 General Product Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Functional Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Thermal Resistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Supply and Input Stage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Supply Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Under Voltage Lock Out / Power On Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Input Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Electrical Characteristics - Supply and Input Stages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Power Stage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Output On-state Resistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Output Timings and Slopes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Inductive Output Clamp . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Electrical Characteristics - Power Stage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Control and Diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Readout of Fault Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Adjustable Slew Rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Electrical Characteristics - Diagnostic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Protection Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Thermal Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Over Voltage Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Short Circuit Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Electrical Characteristics - Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 7 8 8 10 10 10 10 12 13 13 14 14 17 20 20 20 21 22 22 22 23 25 Application Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Dimensioning of serial Resistor at IN pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Further Application Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 Package Outlines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 Datasheet 2 Rev. 1.0, 2009-05-05 Smart Low Side Power Switch BTS3256D BTS 3256D 1 Overview The BTS 3256D is a single channel low-side power switch in PG-TO-252-5-11 package providing embedded protective functions. This HITFET™ is designed for automotive and industrial applications with outstanding protection and control features. The power transistor is a N-channel vertical power MOSFET. The device is controlled by a chip in Smart Power Technology. PG-TO-252-5-11 Basic Features • • • • • • • • • • Slew rate control by dedicated pin enabling EMC optimized switching or PWM operation Max. switching Frequency 12kHz Clear detection of digital fault signal also during fast PWM operation due to restart delay time Thermal and overload protection with time controlled auto restart behavior Time and Power limited active current limitation Minimum RDS(on) achieved with 3.3V or 5V logic input Electrostatic discharge protection (ESD) Very low leakage current Green Product (RoHS compliant) AEC (Automotive Electronics Council) Stress Test Qualification Basic Electrical Data VSOP VD (AZ) RDS(ON,typ) ID(nom) ID(lim) 5.5 V.... 30 V 40 V 10 mΩ 7.5 A 42 A Table 1 Operating voltage Over voltage protection Maximum ON State resistance at Tj = 150°C Typical ON State resistance at Tj = 25°C Nominal load current Minimum current limitation RDS(ON,max) 20 mΩ Type BTS 3256D Datasheet 3 Package PG-TO-252-5-11 Rev. 1.0, 2009-05-05 Smart Low Side Power Switch HITFET - BTS 3256D Overview Digital Diagnostic Features • • • • Over temperature Over load Short circuit Clear detection due to a restart delay time Protection Functions • • • • • Enhanced short circuit protection with time and power limited active current limitation Under voltage lock out Over temperature with time and temperature controlled auto restart Over load with power and time controlled auto restart ESD protection Application • • • • • • All types of resistive, inductive and capacitive loads Suitable for loads with inrush current, such as motors, coils, solenoids or lamps Suitable for EMC optimized switching in slow operation mode Suitable for higher speed PWM controlled loads in fast operation mode Replacement of electromechanical relays, fuses and discrete circuits Micro controller compatible low side power switch with digital feedback for 12V loads Detailed Description The BTS 3256D is an autorestart single channel low-side power switch in PG-TO-252-5-11 package providing embedded protective functions. The device is able to switch all kind of resistive, inductive and capacitive loads. The ESD protection of the VS and IN/Fault pin is referenced to GND. The BTS 3256D is supplied by the VS Pin. This Pin should be connected to a reverse protected battery line. The supply voltage is monitored by the under voltage lock out circuit. The Gate driving unit allows the device to operate in the lowest ohmic range independent of the input signal level, 3.3 V or 5 V . For slow PWM application the device offers smooth turn-on and off due to the embedded edge shaping function, to reduce EMC noise. Furthermore the SRP pin can be used to customize the slew rate of the device in a wide range. The Device is designed for driving automotive loads like motors,valves, coils or bulbs in continous or PWM mode. The over voltage protection is for protection during load-dump or inductive turn off conditions. The power MOSFET is limiting the Drain-Source voltage to a specified level. This function is available even without any supply. The over temperature protection prevents the device from overheating due to overload and/or bad cooling conditions. In order to reduce the device stress the edge shaping is disabled during thermal shutdown. After thermal shutdown the device stays off for the specified restart delay time to enable a clear feedback readout on the microcontroller. After this time the device follows the IN signal state. At high dynamic overload conditions, such as short circuit, the device will either turn off immediately due to the implemented over power limitation, or limit the current for a specified time and then switch off for the restart delay time. Shutdown of the device is triggered if the power dissipation during limitation is above the over power threshold. The short circuit shutdown is a timed restart function. The device will stay off for the specified time and afterwards follow the IN signal state. In order to reduce the device stress the edge shaping is disabled during protective turn off. Datasheet 4 Rev. 1.0, 2009-05-05 Smart Low Side Power Switch HITFET - BTS 3256D BTS 3256D Block Diagram 2 BTS 3256D Block Diagram VS SRP Slew rate control D rain Under voltage lockout Overvoltage Protection Overtemperature Protection IN / Fault Gate Driving Unit ϑ ESD protection Overload Protection Short circuit Protection GND BlockDiagram.emf Figure 1 Block Diagram for the BTS3256D 2.1 Voltage and current naming definition Following figure shows all the terms used in this datasheet, with associated convention for positive values. Vbb V bb IS VS SRP VSRP VIN I IN IN / Fault GND I GND GND Terms.emf VS Drain ID VD RL Figure 2 Terms Datasheet 5 Rev. 1.0, 2009-05-05 Smart Low Side Power Switch HITFET - BTS 3256D Pin Configuration 3 3.1 Pin Configuration Pin Assignment BTS 3256D (top view ) 5 4 GND SRP Drain IN VS PinConfiguration.emf Drain 6 ( Tab) 3 2 1 Figure 3 Pin Configuration 3.2 Pin 1 2 3, Tab 4 5 Pin Definitions and Functions Symbol Function Supply Voltage; Connected to Battery Voltage with Reverse protection Diode and Filter against EMC Control Input and Status Feedback; Digital input 3.3 V or 5 V logic. Drain output; Protected low side power output channel, usually connected via load to battery Slew Rate Preset; Used to define slew rate, see Chapter 7.2 for details Ground; Power ground, pin connection needs to carry the load current from Drain VS IN Drain SRP GND Datasheet 6 Rev. 1.0, 2009-05-05 Smart Low Side Power Switch HITFET - BTS 3256D General Product Characteristics 4 4.1 General Product Characteristics Absolute Maximum Ratings Absolute Maximum Ratings 1) Tj = -40 °C to +150 °C All voltages with respect to ground, positive current flowing into pin (unless otherwise specified) Pos. Voltages 4.1.1 4.1.2 4.1.3 4.1.4 4.1.5 4.1.6 Energies 4.1.7 Unclamped single pulse inductive energy Junction Temperature Storage Temperature ESD Resistivity on input pins (IN,SRP,VS) on Drain and GND pins 1) 2) 3) 4) 5) Parameter Symbol Limit Values Min. Max. 30 452) 40 30 5.5 5.5 0.3 3) Unit Conditions Supply voltage Supply voltage during active clamping Drain voltage Logic input voltage Slew Rate Preset maximum voltages VS VS(pulse) -0.3 -0.3 -0.3 0 -0.3 -0.3 0 V V V V V V J – – – 4) VD VIN VSRP EAS Drain voltage for short circuit protection VD(SC) – 5) ID = 22 A; Vbb = 30 V Temperatures 4.1.8 4.1.9 4.1.10 Tj Tstg VESD IN OUT -40 -55 150 150 °C °C kV – – HBM6) ESD Susceptibility -4 -8 4 8 Not subject to production test, specified by design. Not for DC operation, only for short pulse (i.e. loaddump) for a total of 100 h in full device life. Active clamped. The Device can not be switched on if VD > VD(SC) SRP Pin is driven by an internal current source, so active driving from outside is not required,it may affect lifetime and could cause parameter shifts outside the range given in datasheet 6) ESD susceptibility, HBM according to EIA/JESD 22-A114B, section4 Note: Stresses above the ones listed here may cause permanent damage to the device. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. Note: Integrated protection functions are designed to prevent IC destruction under fault conditions described in the data sheet. Fault conditions are considered as “outside” normal operating range. Protection functions are not designed for continuous repetitive operation. Datasheet 7 Rev. 1.0, 2009-05-05 Smart Low Side Power Switch HITFET - BTS 3256D General Product Characteristics 4.2 Pos. 4.2.1 4.2.2 Functional Range Parameter Supply Voltage Supply current in on Symbol Min. Limit Values Max. 30 3 V mA – – 5.5 – Unit Conditions VS IS Note: Within the functional range the IC operates as described in the circuit description. The electrical characteristics are specified within the conditions given in the related electrical characteristics table. 4.3 Pos. 4.3.1 4.3.2 Thermal Resistance Parameter Junction to Case1) Junction to ambient 1) Symbol Min. Limit Values Typ. 0.9 80 45 Max. 1.1 – – – – – Unit K/W K/W K/W Conditions – @min. footprint @ 6 cm² cooling area, see Figure 4 RthjC RthjA 1) Not subject to production test, specified by design Datasheet 8 Rev. 1.0, 2009-05-05 Smart Low Side Power Switch HITFET - BTS 3256D General Product Characteristics K/W 100 0.5 0.2 0.1 Z thJA 0.05 10 1 0.02 0.01 Single pulse 0.1 -6 10 Figure 4 10 -5 10 -4 10 -3 10 tp -2 10 -1 1 10 10 2 10 s Zth.emf 3 Device on 50 mm × 50 mm × 1.5 mm epoxy PCB FR4 with 6 cm2 (one layer, 70 µm thick) copper area for drain connection. PCB mounted vertical without blown air. Typical transient thermal impedance ZthJA = f(tp) , Pulse D = tp/T, Ta = 25 °C Datasheet 9 Rev. 1.0, 2009-05-05 Smart Low Side Power Switch HITFET - BTS 3256D Supply and Input Stage 5 5.1 Supply and Input Stage Supply Circuit The Supply pin VS is protected against ESD pulses as shown in Figure 5. Due to an internal voltage regulator the device can be supplied from a reverse polarity protected battery line. 5.5V .. 30V BTS3256 D VS ZD Regulator GND Figure 5 Supply Circuit Supply .emf 5.1.1 Under Voltage Lock Out / Power On Reset In order to ensure a stable device behavior under all allowed conditions the Supply voltage VS is monitored by the under voltage lock out circuit. All device functions are only given for supply voltages above under voltage lockout. There is no failure feedback for VS < VSUVON. Device functional off VSUVOFF V SUVON UVLO.emf Figure 6 Under Voltage Lock Out 5.2 Input Circuit Figure 7 shows the input circuit of the BTS 3256D. It’s ensured that the device switches off in case of open input pin. A Zener structure protects the input circuit against ESD pulses. As the BTS 3256D has a supply pin, the operation of the power MOS can be maintained regardless of the voltage on the IN pin, therefore a digital status feedback down to logic low is realized. For readout of the fault information, please refer to Diagnosis “Readout of Fault Information” on Page 20. Datasheet 10 Rev. 1.0, 2009-05-05 Smart Low Side Power Switch HITFET - BTS 3256D Supply and Input Stage IN/Fault 20µA : 100µA GND Figure 7 Input Circuit 1.0mA : 3.0mA input.emf Datasheet 11 Rev. 1.0, 2009-05-05 Smart Low Side Power Switch HITFET - BTS 3256D Supply and Input Stage 5.3 Electrical Characteristics - Supply and Input Stages VS = 5.5 V to 30 V, Tj = -40 °C to +150 °C All voltages with respect to ground, positive current flowing into pin (unless otherwise specified) Pos. Parameter Symbol Min. Under Voltage Lockout Limit Values Typ. – – 0.2 – – 50 2 Max. 5.6 5.5 – 0.8 5.5 100 3 Unit Conditions 5.3.1 5.3.2 5.3.3 5.3.4 5.3.5 5.3.6 5.3.7 UV-switch-on voltage UV-switch-off voltage UV-switch-off hysteresis Low level voltage High level voltage Input pull down current Input pull down current in Fault VSUVON VSUVOFF VSUVHY VINL VINH IIN IIN-Fault – 4.0 – -0.3 2.0 20 1 V V V V V µA mA – – VSUVON - VSUVOFF Digital Input / Fault Feedback – – VIN = 5.3 V; no fault condition VIN = 5.3 V; all fault conditions Datasheet 12 Rev. 1.0, 2009-05-05 Smart Low Side Power Switch HITFET - BTS 3256D Power Stage 6 Power Stage The power stage is built by a N-channel vertical power MOSFET (DMOS). 6.1 Output On-state Resistance The on-state resistance depends on the junction temperature TJ. Figure 8 shows this dependence for the typical on-state resistance RDS(on). 18 16 RDS(on) [ mΩ ] 14 12 10 8 6 -50 -25 0 25 50 75 100 125 150 175 rdson_Tj.emf typ. T [ °C ] Figure 8 Typical On-State Resistance RDSon = f(TJ), VS = 10 V, VIN = high 31 RDS(on) [ mΩ ] 26 21 16 11 6 0 10 20 30 rdson_Vs.emf typ. VS [ V ] Figure 9 Datasheet Typical On-State Resistance RDSon = f(VS), VIN = high, Tambient = 25 °C 13 Rev. 1.0, 2009-05-05 Smart Low Side Power Switch HITFET - BTS 3256D Power Stage 6.2 Output Timings and Slopes A high signal on the input pin causes the power MOSFET to switch on with a dedicated slope which is optimized for low EMC emission. Figure 10 shows the timing definition. IN High Low VD V bb 90 % 80 % |dv/dt|on 20 % 10 % |dv/dt|shaping |dv/dt|off |dv/dt| shaping t OutputTiming.em |dv/dt| shaping tond ton toffd toff t Figure 10 Definition of Power Output Timing for Resistive Load In order to minimize the emission during switching, the BTS 3256D limits the slopes during turn on and off at slow slew rate settings. For best performance of the edge shaping, the supply pin VS should be connected to battery voltage. For supply voltages other than nominal battery, the edge shaping can differ from the Values in the electrical characteristics table below. 6.3 Inductive Output Clamp When switching off inductive loads with low-side switches, the Drain Source voltage VD rises above battery potential, because the inductance intends to continue driving the current. The BTS 3256D is equipped with a voltage clamp mechanism that keeps the Drain-Source voltage VD at a certain level. See Figure 11 for more details. Drain GND output_clamp_curcuitemf . Figure 11 Output Clamp Datasheet 14 Rev. 1.0, 2009-05-05 Smart Low Side Power Switch HITFET - BTS 3256D Power Stage IN High Low ID Overtemperature or short circuit detected t Von VD A Z t V bb t inductive_output_clamp .emf Figure 12 Switching off an inductive Load While demagnetization of inductive loads, energy has to be dissipated in the BTS 3256D. This energy can be calculated with following equation: V bb – V D (AZ)  RL ⋅ IL  L E = V D(AZ) ⋅ ------------------------------- ⋅ ln 1 – ---------------------------------  + I L ⋅ -----RL RL V bb – V D ( AZ )   Following equation simplifies under assumption of RL = 0  V bb 2 1 E = -- LI L ⋅  1 – -------------------------------  2 V bb – V D(AZ)   Figure 13 shows the inductance / current combination the BTS 3256D can handle. For maximum single avalanche energy please also refer to EAS value in “Energies” on Page 7. Datasheet 15 Rev. 1.0, 2009-05-05 Smart Low Side Power Switch HITFET - BTS 3256D Power Stage 10,00 Max. 1,00 L [ mH ] 0,10 0,01 10 ID [ A ] 50 EAS .emf Figure 13 Maximum allowed inductance values for single switch off (EAS) L=f (IL), Tj,start= 150 °C, Vbb=30V, RL= 0 Ω Datasheet 16 Rev. 1.0, 2009-05-05 Smart Low Side Power Switch HITFET - BTS 3256D Power Stage 6.4 Electrical Characteristics - Power Stage VS = 5.5 V to 30 V, Tj = -40 °C to +150 °C All voltages with respect to ground, positive current flowing into pin (unless otherwise specified) Pos. Parameter Symbol Min. Power Supply 6.4.1 On-state resistance RDS(on) Limit Values Typ. 10 Max. – Unit Conditions – mΩ TJ = 25 °C; ID = 20 A; VIN = high VS = 1 0 V TJ = 150 °C; ID = 20 A; VIN = high VS = 1 0 V TJ < 150 °C; TA 85 °C SMD2); VIN = high; VS ≥ 10 V; VDS = 0.5 V TJ < 150 °C; TC = 85 °C; VIN = high VS ≥ 10 V; VDS = 0.5 V; VD = 32 V; VIN = low TJ = 85 °C; VD = 13.5 V; VIN = low – 16 20 mΩ 6.4.2 Nominal load current1) ID(nom) 7.5 8.7 – A 6.4.3 ISO load current1) ID(ISO) 31 33 – A 6.4.4 6.4.5 Off state drain current IDSS – – 6 1 12 2 µA µA1) Dynamic Characteristics 6.4.6 power up settling time tinit – 10 25 µs Vs > 6V first rising edge on IN pin. RL = 2.2 Ω; RSRP = OPEN; Vbb = VS = 13.5 V; see Figure 10 RL = 2.2 Ω; RSRP = OPEN; Vbb = VS = 13.5 V; see Figure 10 RL = 2.2 Ω; RSRP = OPEN; Vbb = VS = 13.5 V; see Figure 10 Timings with fastest slew rate setting 6.4.7 Turn-on delay tond_fast – 4 10 µs 6.4.8 Turn-on time ton_fast – 11 22 µs 6.4.9 Turn-off delay toffd_fast 4 10 15 µs Datasheet 17 Rev. 1.0, 2009-05-05 Smart Low Side Power Switch HITFET - BTS 3256D Power Stage VS = 5.5 V to 30 V, Tj = -40 °C to +150 °C All voltages with respect to ground, positive current flowing into pin (unless otherwise specified) Pos. 6.4.10 Parameter Turn-off time Symbol Min. toff_fast Limit Values Typ. 16 Max. 24 9 Unit µs Conditions RL = 2.2 Ω; RSRP = OPEN; Vbb = VS = 13.5 V; see Figure 10 RL = 2.2 Ω; RSRP = OPEN; Vbb = VS = 13.5 V; see Figure 10 RL = 2.2 Ω; RSRP = OPEN; Vbb = VS = 13.5 V; see Figure 10 RL = 2.2 Ω RSRP = OPEN; Vbb = VS = 13.5 V; see Figure 10 RL = 2.2 Ω; RSRP = GND; Vbb = VS = 13.5 V see Figure 10 RL = 2.2 Ω; RSRP = GND; Vbb = VS = 13.5 V see Figure 10 RL = 2.2 Ω; RSRP = GND; Vbb = VS = 13.5 V see Figure 10 RL = 2.2 Ω; RSRP = GND; Vbb = VS = 13.5 V see Figure 10 1) 6.4.11 Slew rate on -dVD/dton_fast 1.2 2.2 3.8 V/µs 6.4.12 Slew rate off dVD/dtoff_fast 1.2 2.2 3.8 V/µs 6.4.13 Slew rate during edge shaping |dV/dt|shaping_fast – 0.66 – V/µs Timings with slowest slew rate setting 6.4.14 Turn-on delay tond_slow – 22 60 µs 6.4.15 Turn-on time ton_slow – 85 200 µs 6.4.16 Turn-off delay toffd_slow – 75 110 µs 6.4.17 Turn-off time toff_slow 40 150 220 µs Datasheet 18 Rev. 1.0, 2009-05-05 Smart Low Side Power Switch HITFET - BTS 3256D Power Stage VS = 5.5 V to 30 V, Tj = -40 °C to +150 °C All voltages with respect to ground, positive current flowing into pin (unless otherwise specified) Pos. 6.4.18 Parameter Slew rate on Symbol Min. -dVD/dton_slow 0.08 Limit Values Typ. 0.2 Max. 0.6 V/µs RL = 2.2 Ω; RSRP = GND; Vbb = VS = 13.5 V see Figure 10 RL = 2.2 Ω; RSRP = GND; Vbb = VS = 13.5 V see Figure 10 RL = 2.2 Ω; RSRP = GND; Vbb = VS = 13.5 V see Figure 10 ID = -12 A; VS = 0 V ; VIN = 0.0 V 1) Unit Conditions 6.4.19 Slew rate off dVD/dtoff_slow 0.08 0.2 0.6 V/µs 6.4.20 Slew rate during edge shaping |dV/dt|shaping_slow – 0.088 – V/µs Inverse Diode 6.4.21 Inverse Diode forward voltage VD -0.3 -1.0 -1.5 V 1) Not subject to production test, specified by Design. 2) Device mounted according to EIA/JESD 52_2, FR4, 50 × 50 × 1.5 mm; 35µ Cu, 5µ Sn; 6 cm2 . PCB mounted without blown air Datasheet 19 Rev. 1.0, 2009-05-05 Smart Low Side Power Switch HITFET - BTS 3256D Control and Diagnosis 7 Control and Diagnosis The BTS3256D provides digital fault feedback on the IN pin without the need of an ADC. Additonally the device features an adjustable slew rate via the SRP pin. 7.1 Readout of Fault Information The BTS 3256D provides digital status information via an increased current on the IN / Fault pin. The voltage on this pin is pulled down to logic low when a fitting serial resistor is used. An example for the required circuitry is shown in Figure 14. The increased current IIN(fault) is one order of magnitude above the normal operation current IIN. A 3k3 for a 3.3V µC or 5k6 for a 5V µC is recommended. For detailed calculation please refer to “Dimensioning of serial Resistor at IN pin” on Page 26. . V bb V CC V CC Micro controller DO Fault =1 0 0 VS BTS3256 I DO R1 I IN IN/Fault 0 DI GND VDI GND GND Fault_readoutemf . Figure 14 Readout of feedback information and XOR logic in micro 7.2 Adjustable Slew Rate In order to optimize electromagnitic emission, the switching speed of the MOSFET can be adjusted by connecting an external resistor between SRP pin and GND. This allows for balancing between electromagnetic emissions and power dissipation. RSRP-min represents the minimum slew rate Slew ratemin and RSRP-max represents the maximum slew rate Slew ratemax. A short to GND causes the minimum slew rate Slew ratemin. Open pin condition causes the maximum Slew rate Slew ratemax. Figure 15 shows the relation between the resistor value and the slew rate of BTS 3256D. Datasheet 20 Rev. 1.0, 2009-05-05 Smart Low Side Power Switch HITFET - BTS 3256D Control and Diagnosis 7.3 Electrical Characteristics - Diagnostic VS = 5.5 V to 30 V, Tj = -40 °C to +150 °C All voltages with respect to ground, positive current flowing into pin (unless otherwise specified) Pos. Parameter Symbol Min. Slew rate control 7.3.1 Slew ratemin Slew ratemin Slew rate15k Slew rate30k Slew ratemax Limit Values Typ. 0.2 Max. 0.6 Unit Conditions 0.08 V/µs RSRP = 0 Ohm VS = 13.5 V; ohmic load RSRP = 15 kOhm VS = 13.5 V; ohmic load RSRP = 30 kOhm VS = 13.5 V; ohmic load SRP pin open VS = 13.5 V; ohmic load 7.3.2 Slew rate15k 0.2 0.6 – V/µs 7.3.3 Slew rate30k 0.7 1.45 – V/µs 7.3.4 Slew ratemax 1.2 2.2 3.8 V/µs 2,5 2 S lew rate [ V/µs ] 1,5 1 0,5 0 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 R SRP [ kΩ ] Slewrate.emf Figure 15 Typical relation between slew rate and resistor values used on RSRP (Vbat=13.5V) Datasheet 21 Rev. 1.0, 2009-05-05 Smart Low Side Power Switch HITFET - BTS 3256D Protection Functions 8 Protection Functions The device provides embedded protection functions against over temperature, over load and short circuit. Note: Integrated protection functions are designed to prevent IC destruction under fault conditions described in the data sheet. Fault conditions are considered as “outside” normal operation. 8.1 Thermal Protection The device is protected against over temperature resulting from overload and / or bad cooling conditions. The BTS 3256D has a thermal restart function. When overheating occurs, the device switches off for the restart delay time trestart. After this time the device restarts if the temperature is below threshold and the IN has logic high level. The fault feedback is activated during over temperature situation. See Figure 16 for the restart behavior. The diagram naming refers to Figure 14. After delay time , IN is high Over temperature is gone Thermal shutdown IN High Low TJ TJ SD ∆TJSD Don’t care t IIN IINfault IINnom 0 VDI high low trestart t t t thermal fault_autorestart.emf _ Figure 16 Status Feedback via Input Current at Over temperature 8.2 Over Voltage Protection The BTS 3256D is equipped with a voltage clamp mechanism that keeps the Drain-Source voltage VD at a certain level. This stage is also used for inductive clamping. See “Inductive Output Clamp” on Page 14 for details. Datasheet 22 Rev. 1.0, 2009-05-05 Smart Low Side Power Switch HITFET - BTS 3256D Protection Functions 8.3 Short Circuit Protection The condition short circuit is an overload condition of the device. In a short circuit condition, the resulting dI / dt is a function of the short circuit resistance. The BTS3256D incorporates 2 shut down strategies for maximum robustness in the presence of short circuits: - immediate shut down in the case of low ohmic shorts by power detection exceeding Pmax - over temperature shut down in the case of an overload condition The additional feature of this device is a limitation of the load current to Ilim for a maximum time of tlim. If the condition is normalized in a shorter time than tlim, the device stays on, if not the device switch off for trestart and tries to restart in case the IN pin is still high. From first switch off the fault feedback will be activated during trestart and continues until the IN pin goes low or normal condition is reached. Figure 18 shows the behavior mentioned above. In this example first a shorted load occurs which causes the device to limit the current. The device stays on, because the load current returns to normal condition before trestart. In the second switch on, the short circuit is permanent and the device switches OFF after maximum limiting time, stays OFF for the blanking time regardless of the input pin condition and then stays OFF according to the IN pin low condition. The definitions of voltages and currents are in respect to Figure 14. The behavior of VDI also depends on RIN. 70 60 ID [ A ] 50 40 30 20 10 0 Protective Shut Down Safe operation area 10 20 30 Power_limitation.emf VDrain [ V ] Figure 17 Typical Power limitation behavior IDS / VDS Datasheet 23 Rev. 1.0, 2009-05-05 Smart Low Side Power Switch HITFET - BTS 3256D Protection Functions V IN high low ID Inrush Overload Overload situation overload shut off D on’t care t Ilim t lim IDnom tlim IIN IINfault IINnom 0 VDI high low t res tart t t t protection_behaviour.emf Figure 18 Short Circuit during On State, Typical Behavior for Ohmic Loads The case when the device switches on into an existing short circuit - Short circuit type 1- is shown in Figure 17. The test setup for short circuit characterization is shown in Figure 19. The BTS 3256D is a low side switch. Therefore it can be assumed that the micro controller and device GND connection have a low impedance. All impedance in the short circuit path is merged in the short circuit resistance RSC and short circuit inductance LSC. RSC LSC ID Vcc VS IN Drain Vb b 5V Control circuit SRP GND RSR P GND short_circuit_schematic.emf Figure 19 Test Setup for Short Circuit Characterization Test Datasheet 24 BTS3256 Rev. 1.0, 2009-05-05 Smart Low Side Power Switch HITFET - BTS 3256D Protection Functions 8.4 Electrical Characteristics - Protection VS = 5.5 V to 30 V, Tj = -40 °C to +150 °C All voltages with respect to ground, positive current flowing into pin (unless otherwise specified) Pos. Parameter Symbol Min. Thermal Protection 8.4.1 8.4.2 8.4.3 Thermal shut down junction temperature Thermal hysteresis Drain source clamp voltage TJSD Limit Values Typ. 1751) 10 44 Max. – – - Unit Conditions 150 – 40 °C K V – 1) ∆TJSD VD(AZ) Over Voltage Protection ID = 10 mA; VS = 0.0 V; VIN = 0.0 V ID = 8 A ; VS = 0.0 V; VIN = 0.0 V – 45 49 V Short Circuit Protection 8.4.4 8.4.5 8.4.6 8.4.7 current limitation level max. power switch OFF threshold max. time for current limitation before shut OFF restart delay time ID(lim) Pmax tlim trestart 42 300 3.5 50 55 400 5 70 72 650 6.5 100 A W ms ms ohmic load – 2) resistive load – 1) Not subject to production test, specified by design. 2) In case of inductive loads the device needs to increase the VDS voltage during current limitation. This can trigger the over Power protection switch off earlier as tlim. Datasheet 25 Rev. 1.0, 2009-05-05 Smart Low Side Power Switch HITFET - BTS 3256D Application Information 9 Application Information Note: The following information is given as a hint for the implementation of the device only and shall not be regarded as a description or warranty of a certain functionality, condition or quality of the device. 9.1 Dimensioning of serial Resistor at IN pin In order to use the digital feedback function of the device, there must be a serial resistor used between the IN pin and the driver (micro controller). To calculate this serial resistor on the input pin, three device conditions and of course the driver (micro controller) abilities need to be taken into account. Figure 20 shows the circuit used for reading out the digital status. V bb Microcontroller DO I DO V CC V CC VRIN RIN IIN VS IN/Fault BTS3256 DI Fault information 1.0mA SRP : 3.0mA R S RP V DO GND GND VDI 20µA : 100µA GND Fault_R1dim.emf Figure 20 Circuitry to readout fault information Note: This is a very simplified example of an application circuit. The function must be verified in the real application. Conditions to be meet by the circuitry: During normal operation VIN must be higher than VINH,min to switch ON. During fault condition the max. capability of the driver (micro controller) must not be exceeded and the logic low level at DI must be ensured by a voltage drop over the serial resistor RIN while the device fault current is flowing. Conditions in formulas: • µCoutput current,min > µCHIGH,max / RIN > IINFault_min with µCoutput current,min referring to the µC maximum output current capability with µCHIGH,max referring to the maximal high output voltage of the µC driving stage This condition is valid during status feedback operation mode • VIN = µCHIGH,min - (RIN * IIN,max) > VINH,min with µCHIGH,min referring to the minimal high output voltage of the µC driving stage This condition is valid during normal operation mode Datasheet 26 Rev. 1.0, 2009-05-05 Smart Low Side Power Switch HITFET - BTS 3256D Application Information • µCHIGH,max - (RIN * IIN-Fault,min) < µC(DI)L,max with µC(DI)L,max referring to the maximum logic low voltage of the µC input stage The maximum current is either defined by the BTS 3256D or the µC driving stage This condition is valid during status feedback operation mode Out of this conditions the minimum and maximum resistor values can be calculated. For a typical 5V micro controller with output current capability in the 3 mA range, a resistor range from 7.5 kΩ down to 4.5 kΩ can be used. For a typical 3.3V micro controller a range from 4.6 kΩ to 2.5 kΩ is suitable. 9.2 • Further Application Information For further information you may contact http://www.infineon.com/hitfet Datasheet 27 Rev. 1.0, 2009-05-05 Smart Low Side Power Switch HITFET - BTS 3256D Package Outlines 10 Package Outlines 6.5 +0.15 -0.10 2.3 +0.05 -0.10 B A 1 ±0.1 0...0.15 0.9 +0.08 -0.04 1 ±0.1 5.4 ±0.1 9.9 ±0.5 6.22 -0.2 0.8 ±0.15 (4.17) 0.15 max per side 0.51 min 5x0.6 ±0.1 1.14 0.5 +0.08 -0.04 0.1 4.56 0.25 M AB GPT09161 All metal surfaces tin plated, except area of cut. Figure 21 PG-TO-252-5-11 (Plastic Green Thin Outline Package) Green Product (RoHS compliant) To meet the world-wide customer requirements for environmentally friendly products and to be compliant with government regulations the device is available as a green product. Green products are RoHS-Compliant (i.e Pb-free finish on leads and suitable for Pb-free soldering according to IPC/JEDEC J-STD-020). You can find all of our packages, sorts of packing and others in our Infineon Internet Page “Products”: http://www.infineon.com/products. Datasheet 28 Dimensions in mm Rev. 1.0, 2009-05-05 Smart Low Side Power Switch HITFET - BTS 3256D Revision History 11 Version Rev. 1.0 Revision History Date 2009-05-05 Changes released Datasheet Datasheet 29 Rev. 1.0, 2009-05-05 Edition 2009-05-05 Published by Infineon Technologies AG 81726 Munich, Germany © Infineon Technologies AG 2009. All Rights Reserved. Legal Disclaimer The information given in this document shall in no event be regarded as a guarantee of conditions or characteristics (“Beschaffenheitsgarantie”). With respect to any examples or hints given herein, any typical values stated herein and/or any information regarding the application of the device, Infineon Technologies hereby disclaims any and all warranties and liabilities of any kind, including without limitation warranties of non-infringement of intellectual property rights of any third party. Information For further information on technology, delivery terms and conditions and prices please contact your nearest Infineon Technologies Office (www.infineon.com). Warnings Due to technical requirements components may contain dangerous substances. For information on the types in question please contact your nearest Infineon Technologies Office. Infineon Technologies Components may only be used in life-support devices or systems with the express written approval of Infineon Technologies, if a failure of such components can reasonably be expected to cause the failure of that life-support device or system, or to affect the safety or effectiveness of that device or system. Life support devices or systems are intended to be implanted in the human body, or to support and/or maintain and sustain and/or protect human life. If they fail, it is reasonable to assume that the health of the user or other persons may be endangered.