errata revision: * c may 02, 2007 ram9 qdr-i/ddr-i/qdr-ii/ddr- ii errata cy7c129*dv18/cy7c130*dv2 5 cy7c130*bv18/cy7c130*bv25/cy7c132*bv2 5 cy7c131*bv18 / cy7c132*bv18/cy7c139*bv1 8 cy7c191*bv18/cy7c141*av18 / cy7c142*av18 / cy7c151*v18 /cy7c152*v1 8 cypress semiconductor corporation ? 198 champion court san jose , ca 95134-1709 408-943-2600 document #: 001-06217 rev. *c revised:- may 02, 2007 this document describes the doff issue for qdrii/ddrii and the output buffer and jtag issues for qdri/ddri/qdrii/ddrii. details include trigger conditions, possible workarounds and silicon revision applicability. this document should be used to compare to the respective datasheet for the devices to fully describe the device functionality. please contact your local cypress sales representative for availability of the fixed devices and any other questions. devices affected table 1. list of affected devices product status all of the above densities and revisions are available in sample as well as production quantities. qdr/ddr doff pin, output buffer and jtag issues errata summary the following table defines the issues and the fix status for the different devices which are affected. density & revision part numbers architecture 9mb - ram9(90 nm) cy7c130*dv25 qdri/ddri 9mb - ram9(90 nm) cy7c129*dv18 qdrii 18mb - ram9(90nm) cy7c130*bv18 cy7c130*bv25 cy7c132*bv25 qdri/ddri 18mb - ram9(90nm) cy7c131*bv18 cy7c132*bv18 cy7c139*bv18 cy7c191*bv18 qdrii/ddrii 36mb - ram9(90nm) cy7c141*av18 cy7c142*av18 qdrii/ddrii 72mb -ram9(90nm) cy7c151*v18 cy7c152*v18 qdrii/ddrii item issue device fix status 1. doff pin is used for enabling/dis- abling the dll circuitry within the sram. to enable the dll circuitry, doff pin must be externally tied high. the qdr-ii/ddr-ii devices have an internal pull down resistor of ~5k . the value of the external pull- up resistor should be 500 or less in order to ensure dll is enabled. 9mb - ?d? rev - ram9 18mb - ?b? rev - ram9 36mb - ?a? rev - ram9 72mb - ram9 qdr-ii/ddr-ii devices the fix involved removing the in- ternal pull-down resistor on the doff pin. the fix has been im- plemented on the new revision and is now available. ? ?
document #: 001-06217 rev. *c page 2 of 8 table 2. issue definition and fix status for different devices 1. doff pin issue issue definition this issue involves the dll not turning on properly if a large resistor is used (eg:-10k ) as an external pullup resistor to enable the dll. if a 10k or higher pullup resistor is used externally, the voltage on doff is not high enough to enable the dll. parameters affected the functionality of the device will be affected because of the dll is not turning on properly. when the dll is enabled, all ac and dc parameters on the datasheet are met. trigger condition(s) having a 10k or higher external pullup resistor for disabling the doff pin. scope of impact this issue will alter the normal functionality of the qdrii/ddrii devices when the dll is disabled. ? explanation of issue figure 1 shows the doff pin circuit with an internal 5k internal resistor. the fix planned is to disable the internal 5k leaker. workaround 2. o/p buffer enters a locked up unde- fined state after controls or clocks are left floating. no proper read/write access can be done on the device until a dummy read is performed. 9mb - ?d? rev - ram9 18mb - ?b? rev - ram9 36mb - ?a? rev - ram9 72mb - ram9 qdr-i/ddr-i/ qdr-ii/ddr-ii devices the fix has been implemented on the new revision and is now avail- able. 3. the extest function in the jtag test fails when input k clock is floating in the jtag mode. 9mb - ?d? rev - ram9 18mb - ?b? rev - ram9 36mb - ?a? rev - ram9 72mb - ram9 qdr-i/ddr-i/ qdr-ii/ddr-ii devices the fix involved bypassing the zq circuitry in jtag mode. this was done by overriding the zq circuit- ry by the jtag signal. the fix has been implemented on the new re- vision and is now available. figure 1. doff pin with the 5k internal resistor item issue device fix status ? ? ? ? ? ?
? cypress semiconductor corporation, 2005. the information contained herein is subject to change without notice. cypress semic onductor corporation assumes no responsibility for the use of any circuitry other than circuitry embodied in a cypress product. nor does it convey or imply any license under patent or ot her rights. cypress products are not warranted nor intended to be used for medical, life support, life saving, critical control or safety applications, unless pursuant to an express written agr eement with cypress. furthermore, cypress does not authorize its products for use as critical components in life-support systems where a malfunction or failure may reasonably be expected to re sult in significant injury to the user. the inclusion of cypress products in life-support systems application implies that the manufactur er assumes all risk of such use and in doing so indemni fies cypress against all charges. the workaround is to have a low value of external pullup resistor for the doff pin (recommended value is < 500 ). when doff pins from multiple qdr devices are connected through the same pull-up resistors on the board, it is recommended that this doff pin be directly connected to vdd due to the lower effective resistance since the "leakers" are in parallel. figure 2 shows the proposed workaround and the fix planned. fix status fix involved removing the internal pull-down resistor on the doff pin. the fix has been implemented on the new revision and is now available. the new revision is an increment of the existing revision. the following table lists the devices affected, current revision and the new revision after the fix. table 3. list of affected devices and the new revison 2.output buffer issue figure 2. proposed workaround with the 500 external pullup current revision new revision after the fix cy7c129*dv18 cy7c129*ev18 cy7c131*bv18 cy7c131*cv18 cy7c132*bv18 cy7c132*cv18 cy7c139*bv18 cy7c139*cv18 cy7c191*bv18 cy7c191*cv18 cy7c141*av18 cy7c141*bv18 cy7c142*av18 cy7c142*bv18 cy7c151*v18 cy7c151*av18 cy7c152*v18 cy7c152*av18 ? ?
document #: 001-06217 rev. *c page 4 of 8 issue definition this issue involves the output buffer entering an unidentified state when the input signals (only control signals or clocks) are floating during reset or initialization of the memory controller after power up. parameters affected no timing parameters are affected. the device may drive the outputs even though the read operation is not enabled. a dummy read is performed to clear this condition. trigger condition(s) input signals(namely rps# for qdr-i/qdrii , we# and ld# for ddr-i/ddrii) or clocks (k/k# and/or c/c#) are floating during reset or initialization of the memory controller after power up. scope of impact this issue will jeopardize any number of writes or reads which take place after the controls or clock are left floating. this can occur anywhere in the sram access ( all the way from power up of the memory device to transitions taking place for read/write accesses to the memory device) if the above trigger conditions are met. explanation of issue figure 3 shows the output register reset circuit with an sr latch circled. this latch has two inputs with one of them coming from some logic affected by th e clock and rps#(qdr) or we# and ld#(ddr).the issue happens when clocks are glitching/toggling with controls floating. this will cause the sr latch to be taken into an unidentified state. the sr latch will need to be reset by a dummy read operation if this happens. workaround this is viable only if the customer has the trigger conditions met during reset or initialization of the memory controller after power up. in order for the workaround to perform properly, cypress recommends the insertion of a minimum of 16 ?dummy? read operations to every sram device on the board prior to writing any meaningful data into the sram. after this one ?dummy? read operation, the device will perform properly. ?dummy? read is defined as a read operation to the device that is not meant to retrieve required data. the ?dummy? read can be to any address location in the sram. refer to figure 4 for the dummy read implemen- tation. figure 3. output register reset circuit sr latch sr latch
document #: 001-06217 rev. *c page 5 of 8 in systems where multiple srams with multiple rps# lines are used, a dummy read operation will have to be performed on every sram on the board. below is an example sequence of events that can be performed before valid access can be performed on the sram. 1) initialize the memory controller 2) assert rps# low for each of the memory devices note: for all devices with x9 bus configuration, the following sequence needs to be performed: 1) for the 72m / 36m / 18m x9 devices drive address pin a2 / a10 / a3 low respectively and perform dummy read. 2) for the 72m / 36m / 18m x9 devices drive address pin a2 / a10 / a3 high respectively and perform dummy read. if the customer has the trigger conditions met during normal access to the memory then there is no workaround at this point. fix status the fix has been implemented on the new revision and is now available. the new revision is an increment of the existing revision. please refer to table 4 for the list of devices affected, current revision and the new revision after the fix. 3. jtag mode issue issue definition if the input clock (k clock) is left floating when the device is in jtag mode, spurious high frequency noise on this input can be interpreted by the device as valid clocks. this could cause the impedance matching circuitry (zq) on the qdr/ddr devices to periodically load itself with incorrect values. these incorrect values in the zq register could force the outputs into a high-impedance state. the zq circuitry requires at least 1000 valid k clock cycles to drive the outputs from high impedance to low impedance levels. parameters affected figure 4. dummy read implementation /k a ce q(a) q(a+1) q(c) q(c+1) q(e) q(e+1) g k /rps address dataout (q) a ce dq(a) dq (a+1) dq(c) dq (c+1) dq(e) dq (e+1) g we# address dataout (q) dummy read qdrii operation ddrii operation /k a ce q(a) q(a+1) q(c) q(c+1) q(e) q(e+1) g k /rps address dataout (q) a ce dq(a) dq (a+1) dq(c) dq (c+1) dq(e) dq (e+1) g we# address dataout (q) dummy read qdrii operation ddrii operation
document #: 001-06217 rev. *c page 6 of 8 this issue only affects the extest command when the device is in the jtag mode. the normal functionality of the device will not be affected. trigger condition(s) extest command executed immediately after power-up without providing any k clock cycles. scope of impact this issue only impacts the extest command when device is tested in the jtag mode. normal functionality of the device is not affected. explanation of issue impedance matching circuitry (zq) is present on th e qdr/ddr devices to set the desired impedance on the outputs. this zq circuitry is updated every 1000 clock cycles of k clock to ensure that the impedance of the o/p is set to valid state. however, when the device is operated in the jtag mode immediately after power- up, high frequency noise on the input k clock can be treated by the zq circuitry as valid clocks thereby setting the outputs in to a high-impedance mode. if a minimum of 1000 valid k clocks are applied before performing the jtag test, this should clear the zq circuitry and ensure that the outputs are driven to valid impedance levels. workaround elimination of the issue: after power-up, before any valid operations are performed on the device, insert a minimum of 1000 valid clocks on k input. fix status the fix involved bypassing the zq circuitry in jtag mode. this was done by overriding the zq circuitry by the jtag signal. the fix has been implemented on the new revision and is now available. the new revision is an increment of the existing revision. please refer to table 4 for the list of devices affected, current revision and the new revision after the fix.. table 4. list of affected devices and the new revision current revision new revision after the fix cy7c129*dv18 cy7c129*ev18 cy7c130*dv25 cy7c130*ev25 cy7c130*bv18 cy7c130*cv18 cy7c130*bv25 cy7c130*cv25 cy7c132*bv25 cy7c132*cv25 cy7c131*bv18 cy7c131*cv18 cy7c132*bv18 cy7c132*cv18 cy7c139*bv18 cy7c139*cv18 cy7c191*bv18 cy7c191*cv18 cy7c141*av18 cy7c141*bv18 cy7c142*av18 cy7c142*bv18 cy7c151*v18 cy7c151*av18 cy7c152*v18 cy7c152*av18
document #: 001-06217 rev. *c page 7 of 8 references all 90nm qdri/ddri/qdrii/ddrii datasheets:- table 5. list of datasheet spec# for the affected devices spec# part# density architecture 38-05628 cy7c1304dv25 9-mbit qdr(tm) sram 4-word burst 38-05632 cy7c1308dv25 9-mbit ddr-i sram 4-word burst 001-00350 cy7c1292dv18/1294dv18 9-mbit qdr- ii(tm) sram 2-word burst 38-05621 cy7c1316bv18/1916bv18/1318bv18/1320bv18 18-mbit ddr-ii sram 2-word burst 38-05622 cy7c1317bv18/1917bv18/1319bv18/1321bv18 18-mbit ddr-ii sram 4-word burst 38-05623 cy7c1392bv18/1393bv18/1394bv18 18-mbit ddr-ii sio sram 2-word burst 38-05631 cy7c1323bv25 18-mbit ddr-i sram 4-word burst 38-05630 cy7c1305bv25/1307bv25 18-mbit qdr(tm) sram 4-word burst 38-05627 cy7c1303bv25/1306bv25 18-mbit qdr(tm) sram 2-word burst 38-05629 cy7c1305bv18/1307bv18 18-mbit qdr(tm) sram 4-word burst 38-05626 cy7c1303bv18/1306bv18 18-mbit qdr(tm) sram 2-word burst 38-05619 cy7c1310bv18/1910bv18/1312bv18/1314bv18 18-mbit qdr - ii (tm) sram 2-word burst 38-05620 cy7c1311bv18/1911bv18/1313bv18/1315bv18 18-mbit qdr - ii sram 4-word burst 38-05615 cy7c1410av18/1425av18/1412av18/ 1414av18 36-mbit qdr-ii(tm) sram 2-word burst 38-05614 cy7c1411av18/1426av18/1413av18/ 1415av18 36-mbit qdr(tm)-ii sram 4-word burst 38-05616 cy7c1416av18/1427av18/1418av18/1420av18 36-mbit ddr-ii sram 2-word burst 38-05618 cy7c1417av18/1428av18/1419av18/1421av18 36-mbit ddr-ii sram 4-word burst 38-05617 cy7c1422av18/1429av18/1423av18/1424av18 36-mbit ddr-ii sio sram 2-word burst 38-05489 cy7c1510v18/1525v18/1512v18/1514v18 72-mbit qdr-ii sram 2-word burst 38-05363 cy7c1511v18/1526v18/1513v18/1515v18 72-mbit qdr(tm)-ii sram 4-word burst 38-05563 cy7c1516v18/1527v18/1518v18/1520v18 72-mbit ddr-ii sram 2-word burst 38-05565 cy7c1517v18/1528v18/1519v18/1521v18 72-mbit ddr-ii sram 4-word burst 38-05564 cy7c1522v18/1529v18/1523v18/1524v18 72-mbit ddr-ii sio sram 2-word burst
document #: 001-06217 rev. *c page 8 of 8 document history page document title: ram9 qdr-i/ddr-i/qdr-ii/ddr- ii errata document #: 001-06217 rev. *c rev. ecn no. issue date orig. of change description of change ** 419849 see ecn ref new errata for ram9 qdr2/ddr2 srams. *a 493936 see ecn qks added output buffer and jtag mode issues, item#2 and #3 added 9mb qdr-ii burst of 2 and qdr-1/ddr-i part numbers. *b 733176 see ecn njy added missing part numbers in the title for spec#?s 38-05615,38-05614, 38-05363,38-05563 on table 5 on page 7. *c 1030020 see ecn tbe updated the fix status of the three issues, and modified the description for the output buffer workaround for x9 devices on page 5.
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