SLE4501 SIEMENS | Alldatasheet
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Features
@ Internal generation of programming voltage @ Counting range 22 binary bits, nonvolatile storage @ Count output in serial binary code @ Counting operation is executed under on-chip control and cannot be influenced externally @ Disconnection of the operating voltage, even during a counting operation, has no effect on the stored count @ Once the fusible link has been blown, the count is protected against manipulation by internal safety logic. @ Additional 64x8 bit EEPROM area with serial access (byte organization) @ Non-volatile reprogramming of EEPROM area and count through on-chip control onto defined viewport, thus reliable data storage is ensured. @ Extended temperature range from —40°C to +110°C. Pin Configuration Pin Description top vie — — —— (top view) Pin Symbol Function Yop! [eve 1 Vss. | Ground o2f] ste []770 ca ° Clock input - - o3[} 4501 Den 3 ° __| Data input/output ai F]sct 4 v Chip select for data input (active high) and indication of storage operation (active low) 5 cl Count pulse input {active high) 6 71 Fusible link
7 TO Control input test operation
8 Veo Operating range
Siemens Aktiengeselischaft 866
The nonvolatile counter (NC) has a counting range of 22 binary bits and retains its count even after the operating voltage has been disconnected. The safety logic of the device prevents any alteration other than the intended incrementing of the count, which might be caused by supply voltage failures, e.g. during a counting operation. Before the fusible link blows, a desired count can be preset in a test operation. After the fusible link has blown, the count can only be altered by a count request. Thus it is only possible to increment the counter. The count is binary coded and can be serially sampled via a three-wire bus (section 4). A counting operation has priority in any case and will terminate any readout operation that has been started. The 64x8 bit EEPROM area (NVM) is addressed serially by a 1-byte OP code (see program- ming and readout operation). Addresses 16 through 63 can no longer be reprogrammed after the fusible link is blown. Before the fusible link blows, test input TO should be set low for normal operation. An on-chip reset circuit ensures operational reliability. Its functioning is described on page 870. Counting Operation (figure 1c) The integrated circuit consists of a 22-step, asynchronous counter and a nonvolatile, electri- cally reprogrammable memory (EEPROM) for nonvolatile storage of the counter contents. For reasons of operational reliability, the counting operation is executed entirely under on-chip control, The device includes the necessary sequence control for which it generates an internal clock of approx. 50 kHz. A pulse at input Cl causes the asynchronous counter to be incremented by 1. The new count is stored as nonvolatile information. This storage operation is indicated by low at input/output L. During storage no other count events are registered, resulting in a dead time of max. 100 ms in the rated-voltage range. The operating voltage must be main- tained in the rated-voltage range for at least another 10 ms after the start of a storage operation, or else the last count event might not be permanently stored (response time). Counts that have already been stored are not at all affected if the operating voltage is switched off during a storage operation and thus cannot be manipulated. If the operating voltage is reduced during the counting operation, the dead time and the response time will increase, but storage reliability is not affected due to the integrated programming-duration control. The device is inactive outside the operating-voltage window defined by the reset circuit. The nonvolatile safety counter includes overflow protection. If all counter bits are 1, any further count pulses are ignored. Siemens Aktiengeselischaft 867
Count Readout (figure 1d) For sampling the count, input/output L is first set low and then the two instruction bits BO, B1 are clocked in. Afterwards pin L is set high.again. With the trailing edge of any further clock pulse @ the bits appear consecutively at pin D, starting with the most significant bit. The entire count is read out with 22 clock pulses. A low pulse at input/output L switches pin D back to high impedance. A storage operation (nonvolatile counter or 64x8 bit EEPROM) indicated by a low level at pin L has always priority. During this time the device cannot be addressed. A count request will terminate any readout operation that has already been started. Programming of NVM (figure 1a) The input/output C must be set low. Then the 8-bit data word (DO as the 1st bit) is first clocked in, followed by the 8-bit instruction word (consisting of six address bits AO through A5 and two instruction bits BO, B1). After pin L has been set high again, the programming operation, indicated by low at the input/output L, begins subsequently to another clock pulse 9. When the internally controlled storage operation has been completed, L returns to high. In the rated-voltage range the maximum programming time t, is 10 ms. Readout of NVM (figure 1b) The input/output C must be set low. Then the 8-bit instruction word (consisting of 6 address bits AO through AS and two instruction bits BO, B1) is clocked in. After pin L has been set high again, one bit (beginning with DO) of the respective data word appears at pin D with the trailing edge of any further clock pulse $. The entire data word is read out with eight clock pulses. A low pulse at input/output L switches pin D back to high impedance. Fusible Link (figure 4) Blowing of the fusible link has the following irreversible effects: a) The count can now only be altered by count pulses at count input Cl. 'b) It is no longer possible to program the entire NVM in one operation. c) Addresses 16 through 63 of the NVM can no longer be reprogrammed. In order to blow the fusible link, the following conditions must prevail at the inputs (cf. figure 4): a) Test input TO to 17 V b) Test input T1 to 17 V with max. 1 js edge rise time. The fusible link melts within 100 ms. At test input TO there is a temporary peak current of up to 100 mA which can be taken from a storage capacitor, for instance. For the blowing process, test input TO must be connected according to figure 4b, otherwise the device might be destroyed. Siemens Aktiengeselischaft 868
Test Operation (figure 2a, 2b, 2c) Provided the fusible link has not blown the following test operations are possible (T1 must always be kept low and TO high): a) Presetting of count (figure 2a) The input/output L is set low and then the 22 bits constituting the required count are clocked in, starting with the most significant bit. Here it should be noted that the counter bits CBO through CB3 can only be programmed uniformly as 0 or 1. After the two bits of the instruction code have been clocked in, pin L is set high again. Differing values for CBO through CB3 will lead to undefined counts. A high on count input Cl starts the programming operation, which is indicated by a low at pin L. In order to activate the safety logic for the preset count, TO must then be set low and the supply voltage switched off briefly. b) Erasure of entire NVM (figure 2b) Writing into entire NVM (figure 2c) Input/output L is set low and the two bits BO, B1 of the instruction code are clocked in. After switching pin L to high, a high at input #will start the programming operation which is indicated by a low at input/output L. Input # must be kept high for at least 50 ms because the internal timing control for the NVM is switched off and the programming duration (tgp.) is defined for the length of the ® pulse. Siemens Aktiengesellschaft 869
a) TO low or after blowing the fusible link: Function Bo | B1 Program NVM. 1 (0 Read out NVM 1 |1 Read out counter 0 1 b) TO high (test operation): Started by pulse at Cl Function BO BI Preset counter 0 0 Started by clock pulse® Function BO B1 Erase entire NVM 1 0 Write into entire NVM 1 Reset Function For reasons of operational reliability the device contains an internal reset circuit that limits the active range to that of a voltage window. The lower limit is at a maximum of 4.5 V and the upper limit at a minimum of 5.5 V. If the supply voltage is outside the window, even if only because of spikes, the device will reset. As soon as the prescribed voltage window has been reached again, a reset routine runs automatically, this being indicated by a low at input/output L resulting in a dead time of max. 100 ms in the rated-voltage range. Siemens Aktiengesellschaft 870
Description Symbol | min Unit Supply voltage | Veo -03 v Input voltage vi -03 v Thermal resistance system ~ air Kw Operating Range Siemens Aktiengeselischaft 871
Description | Symbot_| min | typ max | Unit Supply voltage Veo 475 [ses fv ‘Supply current Tec 7 1.10 mA Inputs’) v, | 05 To 8 v (@.0,C1, 0,71) Va 22 Voc v (TO) Va | 4.95 Veo Vv (@,C,.c1,0,71) In 10 yA (70) My 100 | WA Outputs (D, L) I, 1 mA (open drain, V,= 0.5 V) In A Counting dead time laeas 100 ms ‘Counting response time tress 40 ms Clock th 5 1000 us t 5 Hs t 1 ys Interval start pulse/ trailing edge C tet | 5 us Count input Cl to, 5 us Programming time NVM (per byte) 10 ms Programming time NVM (total memory) topr 50 100 ms Blowing of fusible link: To Ya 167 173 v Iy | 100 mA aal Va 16.7 173 Vv Ty 10 pA | 1 us i 100 ms 1) The following particular level conditions apply to the input @ in case of test operating modes: © (test operation) yw | 05 06 v Ye 30 | Mee vo ‘Siemens Aktiengesellschaft 872
Generation EEPROM Controt Fusible Link a Da ou 22-Bit Shift Register Register {> | (Instruction Code) Programming Read Circuit Power-On r4 I] Detection 22- Bit Register 1 22-Bit Register 2 | « | Nonvolatile Nonvotatile (Redundant } (Redundant) Yoo Vos Siemens Aktiengesellschaft 873
Figure 2a Presetting Count on NC Forced a Pleternatty at it Figure 2b Erasure of Entire NVM TO J L eo ny
0 ZA e1_ LZ ZA
i Figure 2c Writing into Entire NVM o_O i Me ee SA TLS fone Intern Vite et he Siemens Aktiengeselischaft 875