L9700D

L9700 ® HEX PRECISION LIMITER . .. . .. HIGH PERFORMANCE CLAMPING AT GROUND AND POSITIVE REFERENCE VOLTAGE FAST ACTIVE CLAMPING OPERATING RANGE 4.75 - 5.25 V SINGLE VOLTAGE FOR SUPPLY AND POSITIVE REFERENCE LOW QUIESCENT CURRENT LOW INPUT LEAKAGE CURRENT ) s ( ct u d o r P e t e l o DESCRIPTION The L9700 is a monolithic circuit which is suited for input protection and voltage clamping purpose. The limiting function is referred to ground and the positive supply voltage. One single element contains six independent channels. Very fast speed is achieved by internal feedback and the application of a new vertical PNP-transistor with isolated collector. ) (s MINIDIP s b O SO8 ORDERING NUMBERS: L9700 (DIP) L9700D (SO8) t c u BLOCK DIAGRAM d o r P e t e l o s b O September 2000 This is advanced information on a new product now in development or undergoing evaluation. Details are subject to change without notice. 1 L9700 ABSOLUTE MAXIMUM RATINGS Symbol Parameter Value 20 30 Unit V mA –55 to 150 °C mW Supply Voltage Input Current per Channel VCC IIN Tj, Tstg Ptot Junction and Storage Temperature 650 Total Power Dissipation (Tamb = 85°C) Note: The circuit is ESD protected according to MIL-STD-883C THERMAL DATA Symbol Rth j-amb Parameter Thermal Resistance Junction to Ambient Max. MINIDIP SO8 Unit 100 200 °C/W ) s ( ct u d o PIN CONNECTION r P e t e l o ) (s s b O t c u d o r ELECTRICAL CHARACTERISTICS (VCC = 5V, TJ = –40 to 125°C unless otherwise specified) P e Symbol Parameter Supply Voltage VCC ICC Supply Current Vcis Static Input Clamping Voltage t e l o s b O IIN Vcld (*) tS (*) RIN (*) Test condition Min. 4.75 Typ. 1.5 Negative IIN = –10mA Positive IIN = +10mA –250 VCC Max. 5.25 3 0 VCC +250 Unit V mA mV Input Current (static) VIN = 0 VIN = VCC VIN = 50mV VIN = VCC –50mV 15 15 5 5 µA µA µA µA Dynamic Input Clamping Voltage IIN = ± 10mA, tR = 5ns Positive Overshoot Negative Overshoot See fig. 2 400 400 mV mV 20 5 ns Setting Time Dynamic Input Resistance Ω (*) Design limits are guaranteed by statistical control on production samples over the indicated temperature and supply voltage ranges. These limits are not used to calculate outgoing quality levels. 2/8 L9700 Figure 1 : DC INPUT CHARACTERISTIC Limit Points of the Characteristic Approximation. ) s ( ct u d o r P e Figure 2 : Dynamical Input Characteristics. 2a ) (s t e l o s b O t c u d o r P e t e l o s b O 3/8 L9700 Figure 2 : Dynamical Input Characteristics (continued) . 2b ) s ( ct u d o r P e t e l o APPLICATION INFORMATION Most integrated circuits, both HNMOS and bipolar, are very sensitive to positive and negative overvoltages on the supply and at the inputs. These transients occur in large numbers and with different magnitudes in the automotive environment, making adequate protection for devices ai-med at it indispensible. Overvoltages on the supply line are faced through high voltage integration technologies or through external protection (transil, varistor). Signal inputs are generally protected using clamp diodes to the supply and ground, and a current limiter resistor. However, such solutions do not always completely satisfy the protection specifications in terms of intervention speed, negative clamping and current leakage high enough to change analog signals. The L9700 device combines a high intervention speed with a high precision positive and negative )- s ( t c u d o r P e t e l o s b O 4/8 s b O clamp and a low current leakage providing the optimal solution to the problems of the automotive environment. The high intervention speed, due to the pre-bias of the limiter stage and internal feedback, limits the voltage overshoot and avoid the use of external capacitors for the limitation of the transient rise times. Figure 3 illustrates a typical automotive application scheme. The resistor RS limits the input current of the device and is therefore dimensioned considering the characteristics of the transients to be eliminated. Consequently : RS = Vtransient Peak IIN MAX The CIN capacitors must be used only on analog inputs because they present a low impedance during the sampling period. L9700 Figure 3 : Typical Application. ) s ( ct u d o r P e The minimum value for CIN is determined by the accuracy required, the time taken to sample the input and the input impedance during that time, while the maximum value is determined by the required frequency response and the value of RS. Thus for a resistive input A/D connector where : TS = Sample time (Seconds) RD = Device input resistance (Ohms) VIN = Input voltage (Volts) k = Required accuracy (%) Q1 = Charge on capacitor before sampling Q2 = Charge on capacitor after sampling ID = Device input current (Amps) Thus : k ⋅ Q1 Q1– Q2 = 100 ) (s t c u d o r let P e O o s b t e l o s b O but and so that and so Q1 = CIN VIN Q1– Q2 = ID – TS k ⋅ CIN – VIN 100 ID ⋅ TS CIN (min) = Farad VIN ⋅ k 100 ⋅ TS CIN (min) = Farad k ⋅ RD ID TS = The calculation for a sample and hold type convertor is even simpler : k = Required accuracy (%) CH = Hold capacitor (Farad) CIN (min) = 100 ⋅ CH Farad k 5/8 L9700 mm DIM. MIN. A TYP. inch MAX. MIN. 3.32 TYP. 0.131 a1 0.51 B 1.15 1.65 0.045 0.065 b 0.356 0.55 0.014 0.022 b1 0.204 0.304 0.008 0.012 0.020 D 10.92 E 7.95 9.75 0.313 0.384 2.54 0.100 e3 7.62 0.300 e4 7.62 0.300 6.6 0.260 I 5.08 0.200 3.81 Z 0.125 1.52 0.150 0.060 ) (s t c u d o r P e t e l o s b O 6/8 u d o F 3.18 ) s ( ct 0.430 e L OUTLINE AND MECHANICAL DATA MAX. r P e s b O t e l o Minidip L9700 mm DIM. MIN. TYP. A inch MAX. MIN. TYP. a1 1.75 0.1 0.25 a2 0.069 0.004 0.010 1.65 0.065 a3 0.65 0.85 0.026 0.033 b 0.35 0.48 0.014 0.019 b1 0.19 0.25 0.007 0.010 C 0.25 0.5 0.010 0.020 c1 OUTLINE AND MECHANICAL DATA MAX. ) s ( ct 45° (typ.) D (1) 4.8 5.0 0.189 0.197 E 5.8 6.2 0.228 0.244 e 1.27 0.050 e3 3.81 0.150 F (1) 3.8 4.0 0.15 0.157 L 0.4 1.27 0.016 0.050 M 0.6 0.024 8 ° (max.) S (1) D and F do not include mold flash or protrusions. Mold flash or potrusions shall not exceed 0.15mm (.006inch). ) (s u d o r P e s b O t e l o SO8 t c u d o r P e t e l o s b O 7/8 L9700 ) s ( ct u d o r P e t e l o ) (s s b O t c u d o r P e t e l o s b O Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specification mentioned in this publication are subject to change without notice. This publication supersedes and replaces all information previously supplied. STMicroelectronics products are not authorized for use as critical components in life support devices or systems without express written approval of STMicroelectronics. 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