MC33298 Motorola, MC33298 Datasheet
MC33298
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MC33298 Summary of contents
Page 1
... Octal Serial Switch with Serial Peripheral Interface I/O The MC33298 is an eight output low side power switch with 8 bit serial input control. The MC33298 is a versatile circuit designed for automotive applications, but is well suited for other environments. The MC33298 incorporates SMARTMOS technology, with CMOS logic, bipolar/MOS analog circuitry, and DMOS power MOSFETs ...
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... Only the output experiencing an over current condition shuts down at 3 6.0 A after 100 s delay, with SFPD pin grounded. All outputs will continue to operate in a current limit mode, with no shutdown, if the SPFD pin MC33298 Figure 1. Simplified Block Diagram V PWR Voltage ...
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... See Figure 20 for Thermal Model. 12. Thermal resistance from Junction–to–Ambient with all outputs “on” and dissipating equal power. 13. Thermal resistance from Junction–to–Ambient with a single output “on.” MOTOROLA ANALOG IC DEVICE DATA MC33298 Symbol Value V PWR(sus) –1.5 to 26.5 V PWR(pk) – ...
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... Output “Off” Open Load Detect Current is the current required to flow through the load for the purpose of detecting the existence of an open condition when the specific output is commanded to be “off.” 6. Output leakage current measured with output “off” and This parameter is guaranteed by design but is not production tested. 4 MC33298 (Characteristics noted under conditions of 4.5 V Symbol Min V PWR(qf) 5 ...
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... V DD Figure 2. Input Timing Switch Characteristics RSTB 0 wRSTB CSB 0 lead 0 SCLK SI Don’t Care MOTOROLA ANALOG IC DEVICE DATA MC33298 (Characteristics noted under conditions of 4.5 V Symbol I(hys RSTB I SFPD V SOH V DD –1 SOL SOT – ...
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... Time required for output status data to be terminated at SO. 5. Time required to obtain valid data out from SO following the rise of SCLK. 6. Clock period includes 75 ns rise plus 75 ns fall transition time in addition to clock high and low time. 6 MC33298 (Characteristics noted under conditions of 4.5 V Symbol t r ...
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... SO (low–to–high) waveform is for SO output with internal conditions such that SO output is high except when an output is disabled as a result of detecting a circuit fault with CSB in a High Logic state (e.g., shorted load 5 Pull– 2.0 k MC33298 SO Under Test fSI ...
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... CSB rises. Represents an output commanded “on” while having an existing output short (overcurrent) to supply. 2. SFPD pin Delay Test Circuit 5 PWR = 2.0 A (Output “On”) MC33298 Output Under Test Delay Waveforms t fSI ...
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... This would represent a very large amount of power to be consumed by the device itself and not available for load use. In operation the MC33298 functions as an eight output serial switch serving as a microcontroller (MCU) bus expander and buffer with fault management and fault reporting features ...
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... MCUs available from Motorola and other semiconductor manufacturers. SPI reduces the number of pins necessary for input/output (I/O) on the MC33298. It also offers an easy means of expanding the I/O function using few MCU pins. The SPI system of communication consists of the MCU transmitting, and in return, receiving one databit of information per clock cycle ...
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... If the SFPD pin is tied 5.0 V the MC33298 output(s) will remain “on” current limited mode of operation upon encountering a load short to supply. If the SFPD pin is grounded, a short circuit will immediately shut down only the output affected ...
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... MC33298 Figure 16. MOTOROLA ANALOG IC DEVICE DATA ...
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... MCU, at the end of the repeated word, serves as a confirmation of data bus integrity (1). At startup, the MC33298 will take 25 to 100 s before a repeat of the first word can give the actual status of the outputs. Therefore, the first word should be repeated at least 100 s later to verify the status of the outputs ...
Page 14
... Output Off Open Load Fault is indicated when the output voltage is less than the Output Threshold Voltage (V Thres ) of 0 Since the MC33298 outputs function as switches, during normal operation, each MOSFET output should either be completely turned “on” or “off.” By design the threshold voltage was selected to be between the “ ...
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... Proper operation at V PWR voltages below 5.5 V cannot be guaranteed. Deciphering Fault Type The MC33298 SO pin can be used to understand what kind of system fault has occurred. With eight outputs having open load, over current and over temperature faults, a total of 25 different faults are possible. The SO status word received by the MCU will be compared with the word sent to the MC33298 during the previous write cycle ...
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... Thermal Performance Figure 20 shows the worst case thermal component parameters values for the MC33298 in the 20 pin plastic power DIP and the SOP–24 wide body surface mount package. The power DIP package has Pins 5, 6, 15, and 16 connected directly to the lead frame flag ...
Page 17
... Pin DIP 7.0 0.002 SOP–24L 7.0 0.002 * = C/ PWR = W, and MOTOROLA ANALOG IC DEVICE DATA MC33298 Junction Temperature Node (Volts represent Die Surface Temperature) Output Flag Temperature Node C pkg = C flag + C PC Board Ambient Temperature Node ...
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... AMBIENT TEMPERATURE ( C) Figure 23. Maximum Output “On” Resistance 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 – MC33298 Figure 22. Maximum SOP Package Steady State Ouput Current versus Ambient Temperature 2.5 1 Output “On” (40 C/W) 2.0 4 Outputs “On” (35 C/W) 1.5 1.0 8 Outputs “On” (34 C/W) 0.5 0 100 125 150 – 50 – ...
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... Other noteworthy advantages the MC33298 offers are conservation of power and board space, requirement of fewer application components, and enhanced application reliability. The MC33298 is available at a fraction of the cost required for discrete component implementation and represents true value. The MC33298 represents a cost effective device having advanced performance and features and worthy of consideration ...
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... SELECT THE DESIRED OUTPUTS TOP LDA #$55 Select outputs of MC33298 to be turned “on.” This instruction is left inside the loop to include STA VALUE changes while running the program. A set bit will cause the associated MC33298 output to be “off.” The value register is uncorrupted by the serial–to–parallel conversion. ...
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... One, so set the DATA OUT bit. GOON BSET 6,PORTA ;Set the SCLK. Serial Output pin of the MC33298 changes state on the rising edge of the SCLK. Read the next bit coming from the MC33298. BRCLR 0,PORTA, ;Read the bit and branch if Zero. LSB of DATAIN is already cleared due to the ASL above. ...
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... Inner Loop Count INNRLP DECX ;0–FF, FF–FE, BNE INNRLP ;6CYC* 256* 1.0 s/CYC = 1.53 ms DECA ;4–3. 3–2, 2–1, 1–0 BNE OUTLP ;1545CYC* 4*1.0 s/CYC = 6.18 ms LDA DATA1 ;Recover Accumulator value. RTS ;Return from subroutine. ORG $1FF FDB INIT 22 MC33298 1–0 256 loops. MOTOROLA ANALOG IC DEVICE DATA ...
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... 0.25 (0.010) –A– 24X 0.010 (0.25 –T– SEATING PLANE G 22X MOTOROLA ANALOG IC DEVICE DATA MC33298 OUTLINE DIMENSIONS P SUFFIX PLASTIC PACKAGE CASE 738–03 DIP (16+2+2) ISSUE 0.25 (0.010 SUFFIX PLASTIC PACKAGE CASE 751E– ...
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... JAPAN: Nippon Motorola Ltd.; Tatsumi–SPD–JLDC, 6F Seibu–Butsuryu–Center, 3–14–2 Tatsumi Koto–Ku, Tokyo 135, Japan. 03–81–3521–8315 ASIA/PACIFIC: Motorola Semiconductors H.K. Ltd.; 8B Tai Ping Industrial Park, 51 Ting Kok Road, Tai Po, N.T., Hong Kong. 852–26629298 MOTOROLA ANALOG IC DEVICE DATA *MC33298/D* MC33298/D ...