L9822N octal serial solenoid driver . eight low r dson dmos outputs (0.5 w at i o = 1a @ 25 c v cc = 5v 5%) . 8 bit serial input data (spi) . 8 bit serial diagnostic output for overload and open circuit conditions . output short circuit protection . chip enable select function (active low) . internal 35v clamping for each out- put . cascadable with another octal driver . low quiescent current (10ma max.) . package power so20 description the L9822N is an octal low side solenoid driver rea lized in multipower-bcd technology particularly suited for driving lamps, relays and solenoids in au- block diagram powerso20 ordering number: L9822N tomotive environment. the dmos outpts L9822N has a very low power consumption. data is transmitted serially to the device using the serial peripheral interface (spi) protocol. the L9822N features the outputs status monitoring function. multipower bcd technology october 1997 1/9
pin connections (top view) gnd so v cc reset out7 out5 out6 out4 n.c. n.c. out3 out2 out0 out1 ce sclk si gnd 1 3 2 4 5 6 7 8 9 18 17 16 15 14 12 13 11 19 10 20 gnd gnd d94at119a thermal data symbol parameter value unit r th j-case thermal resistance junction-case max. 1.5 c/w r th j-amb thermal resistance junction-ambient max. 60 c/w absolute maximum ratings symbol parameter value unit v cc dc logic supply C 0.7 7 v v o output voltage C 0.7 40 v i i input transient current (ce, si, sclk, reset, so) : duration time t = 1s, v i < 0 v i > v cc C 25 + 25 ma ma t j , t stg junction and storage temperature range C 40 150 c L9822N 2/9
v cc logic supply voltage - nominally 5v ground device ground. this ground applies for the logic cir- cuits as well as the power output stages. reset asynchronous reset for the output stages, the paral- lel latch and the shift register inside the L9822Nsp. this pin is active low and it must not be left floating. a power on clear function may be implemented con- necting this pin to v cc with an external resistor and to ground with an external capacitor. ce chip enable. data is transferred from the shift regi- sters to the outputs on the rising edge of this signal. the falling edge of this signal sets the shift register with the output voltage sense bits coming from the output stages. the output driver for the so pin is enabled when this pin is low. so serial output. this pin is the serial output from the shift register and it is tri-stated when ce is high. a high for a data bit on this pin indicates that the par- ticular output is high. a low on this pin for a data bit indicates that the output is low. comparing the serial output bits with the previous serial input bits the external microcontroller imple- ments the diagnostic data supplied by the l9822. si serial input. this pin is the serial data input. a high on this pin will program a particular output to be off, while a low will turn it on. sclk serial clock. this pin clocks the shift register. new so data will appear on every rising edge of this pin and new si data will be latched on every sclks fal- ling edge into the shift register. outputs 00-07 power output pins. the input and output bits corres- ponding to 07 are sent and received first via the spi bus and 00 is the last. the outputs are provided with current limiting and voltage sense functions for fault indication and pro- tection. the nominal load current for these outputs is 500ma. the outputs also have on board clamps set at about 36v for recirculation of inductive load current. pin description electrical characteristics (v cc = 5v 5%. t j = C 40 to 125 c ; unless otherwise speciifed) symbol parameter test conditions min. typ. max. unit v oc output clamping volt. i o = 0.5a, output programmed off 30 35 40 v e oc out. clamping energy i o = 0.5a, when on 20 mj i off out. leakage current v o = 24v, output progr. off 1 ma r dson on resistance output progr. on i o = 0.5a i o = 0.75a i o = 1a with fault reset disabled 0.53 0.53 0.53 1 1 1 w w w t phl turn-on delay i o = 500ma no reactive load 10 m s t p turn-off delay i o = 500ma no reactive load 10 m s v oref fault refer. voltage output progr. off fault detected if v o > v oref 1.6 2 v t ud fault reset delay (after ce l to h transition) see fig. 3 75 250 m s v off output off voltage output pin floating.coutput progr. off, 1.0 v L9822N 3/9
electrical characteristics (continued) symbol parameter test conditions min. typ. max. unit input buffer (si, ce, sclk and reset pins) v tC threshold voltage at falling edge 0.2v cc v v t+ threshold voltage at rising edge 0.7v cc v v h hysteresis voltage v t+ C v tC 1.45 v i i input current v cc = 5.25v, 0 < v i < v cc C 10 + 10 m a c i input capacitance 0 < v i < v cc 20 pf output buffer (so pin) v sol output low voltage i o = 1.6ma 0.4 v v soh output high voltage i o = 0.8ma v cc C 1.3v v i sotl output tristate leakage current 0 < v o < v cc , ce pin held high, v cc = 5.25v C 10 10 m a c so output capacitance 0 < v o < v cc ce pin held high 20 pf i cc quiescent supply current at v cc pin all outputs progr. on. i o = 0.5a per output simultaneously 10 ma serial peripheral interface (see fig. 2, timing diagram) f op operating frequency d.c. 2 mhz t lead enable lead time 250 ns t lag enable lag time 250 ns t wsckh clock high time 200 ns t wsckl clock low time 200 ns t su data setup time 75 ns t h data hold time 75 ns t en enable time 250 ns t dis disable time 250 ns t v data valid time 100 ns t rso rise time (so output) v cc = 20 to 70% c l = 200pf 50 ns t fso fall time (so output) v cc = 70 to 20% c l = 200pf 50 ns t rsi rise time spi inputs (sck, si, ce) v cc = 20 to 70% c l = 200pf 200 ns t fsi fall time spi inputs (sclk, si, ce) v cc = 70 to 20% c l = 200pf 200 ns t ho output data hold time 0 ns L9822N 4/9
the L9822N dmos output is a low operating power device featu-ring, eight 1 w r dson dmos drivers with transient protection circuits in output stages. each channel is independently controlled by an out- put latch and a common reset line which disables all eight outputs. the driver has low saturation and short circuit protection and can drive inductive and re- sistive loads such as solenoids, lamps and relais. data is transmitted to the device serially using the se- rial peripheral interface (spi) protocol. the circuit re- ceives 8 bit serial data by means of the serial input (si) which is stored in an internal register to control the output drivers. the serial output (so) provides 8 bit of diagnostic data representing the voltage level at the driver output. this allows the microprocessor to diagnose the condition of the output drivers. the output saturation voltage is monitored by a comparator for an out of saturation condition and is able to unlatch the particular driver through the fault reset line. this circuit is also cascadable with ano- ther octal driver in order to jam 8 bit multiple data. the device is selected when the chip enable (ce) line is low. additionally the (so) is placed in a tri-state mode when the device is deselected. the negative edge of the (ce) transfers the voltage level of the drivers to the shift register and the positive edge of the (ce) latches the new data from the shift register to the dri- vers. when ce is low, data bit contained into the shift register is transferred to so output at every sclk positive transition while data bit present at si input is latched into the shift register on every sclk negative transition. internal blocks description the internal architecture of the device is based on the three internal major blocks : the octal shift regi- ster for talking to the spi bus, the octal latch for hol- ding control bits written into the device and the octal load driver array. shift register the shift register has both serial and parallel inputs and serial and parallel outputs. the serial input ac- cepts data from the spi bus and the serial output si- multaneously sends data into the spi bus. the parallel outputs are latched into the parallel latch in- side the L9822N at the end of a data transfer. the parallel inputs jam diagnostic data into the shift re- gister at the beginning of a data transfer cycle. parallel latch the parallel latch holds the input data from the shift register. this data then actuates the output stages. individual registers in the latch may be cleared by fault conditions in order to protect the overloaded output stages. the entire latch may also be cleared by the reset sig nal. output stages the output stages provide an active low drive signal suitable for 0.75a continuous loads. the outputs have internal zeners set to 36 volts to clamp induc- tive transients at turn-off. each output also has a voltage comparator observing the output node. if the voltage exceeds 1.8v on an on output pin, a fault condition is assumed and the latch driving this par- ticular stage is reset, turning the output off to pro- tect it. the timing of this action is described below. these comparators also provide diagnostic feed- back data to the shift register. additionally, the com- parators contain an internal pulldown current which will cause the cell to indicate a low output voltage if the output is programmed off and the output pin is open circuited. timing data transfer figure #2 shows the overall timing diagram from a byte transfer to and from the L9822Nsp using the spi bus. ce high to low transition the action begins when the chip enable (ce) pin is pulled low. the tri-state serial output (so) pin driver will be enabled entire time that ce is low. at the fal- ling edge of the ce pin, the diagnostic data from the voltage comparators in the output stages will be lat- ched into the shift register. if a particular output is high, a logic one will be jammed into that bit in the shift register. if the output is low, a logic zero will be loaded there. the most significant bit (07) should be presented at the serial input (si) pin. a zero at this pin will program an output on, while a one will pro- gram the output off. sclk transitions the serial clock (sclk) pin should then be pulled high. at this point the diagnostic bit from the most si- gnificant output (07) will appear at the so pin. a high here indicates that the 07 pin is higher than 1.8v. the sclk pin should then be toggled low then high. new so data will appear following every rising edge of sclk and new si data will be latched into the L9822N shift register on the falling edges. an unli- mited amount of data may be shifted through the de- vice shift register (into the si pin and out the so pin), allowing the other spi devices to be cascaded in a daisy chain with the L9822N. functional description L9822N 5/9
ce low to high transition once the last data bit has been shifted into the L9822Nsp, the ce pin should be pulled high. at the rising edge of ce the shift register data is lat- ched into the parallel latch and the output stages will be actuated by the new data. an internal 160 m s de- lay timer will also be started at this rising edge (see t ud ). during the 160 m s period, the outputs will be protected only by the analog current limiting circuits since the resetting of the parallel latches by faults conditions will be inhibited during this period. this al- lows the part to overcome any high inrush currents that may flow immediately after turn on. once the delay period has elapsed, the output voltages are sensed by the comparators and any output with vol- tages higher than 1.8v are latched off. it should be noted that the sclk pin should be low at both tran- sitions of the ce pin to avoid any false clocking of the shift register. the sclk input is gated by the ce pin, so that the sclk pin is ignored whenever the ce pin is high. fault conditions check checking for fault conditions may be done in the fol- lowing way. clock in a new control byte. wait 160 microseconds or so to allow the outputs to settle. clock in the same control byte and observe the diag- nostic data that comes out of the device. the diag- nostic bits should be identical to the bits that were first clocked in. any differences would point to a fault on that output. if the output was programmed on by clocking in a zero, and a one came back as the dia- gnostic bit for that output, the output pin was still high and a short circuit or overload condition exists. if the output was programmed off by clocking in a one, and a zero came back as the diagnostic bit for that output, nothing had pulled the output pin high and it must be floating, so an open circuit condition exists for that output. figure 1 : byte timing with asynchronous reset. L9822N 6/9
figure 2 : timing diagram. figure 3 : typical application circuit. n L9822N 7/9
e a2 a e a1 pso20mec detail a t d 110 11 20 e1 e2 h x 45 detail a lead slug a3 s gage plane 0.35 l detail b r detail b (coplanarity) gc -c- seating plane e3 b c n n powerso20 package mechanical data dim. mm inch min. typ. max. min. typ. max. a 3.60 0.1417 a1 0.10 0.30 0.0039 0.0118 a2 3.30 0.1299 a3 0 0.10 0 0.0039 b 0.40 0.53 0.0157 0.0209 c 0.23 0.32 0.009 0.0126 d (1) 15.80 16.00 0.6220 0.6299 e 13.90 14.50 0.5472 0.570 e 1.27 0.050 e3 11.43 0.450 e1 (1) 10.90 11.10 0.4291 0.437 e2 2.90 0.1141 g 0 0.10 0 0.0039 h 1.10 l 0.80 1.10 0.0314 0.0433 n 10 (max.) s 8 (max.) t 10.0 0.3937 (1) "d and e1" do not include mold flash or protrusions - mold flash or protrusions shall not exceed 0.15mm (0.006") L9822N 8/9
information furnished is believed to be accurate and reliable. however, sgs-thomson microelectronics 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 resu lt from its use. no license is granted by implication or otherwise under any patent or patent rights of sgs-thomson microelectronics. speci fication mentioned in this publication are subject to change without notice. this publication supersedes and replaces all information pr eviously supplied. sgs-thomson microelectronics products are not authorized for use as critical components in life support devices or sy stems without express written approval of sgs-thomson microelectronics. ? 1997 sgs-thomson microelectronics C printed in italy C all rights reserved powerso-20 ? is a trademark of sgs-thomson microelectronics sgs-thomson microelectronics group of companies australia - brazil - canada - china - france - germany - hong kong - italy - japan - korea - malaysia - malta - morocco - the netherlands - singapore - spain - sweden - switzerland - taiwan - thailand - united kingdom - u.s.a. L9822N 9/9
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