IS42SM16200C IS42RM16200C IS42VM16200C 1M x 16Bits x 2Banks Low Power Synchronous DRAM Description These IS42SM/RM/VM16200C are low power 33,554,432 bits CMOS Synchronous DRAM organized as 2 banks of 1,048,576 words x 16 bits. These products are offering fully synchronous operation and are referenced to a positive edge of the clock. All inputs and outputs are synchronized with the rising edge of the clock input. The data paths are internally pipelined to achieve high bandwidth. All input and output voltage levels are compatible with LVCMOS. Features JEDEC standard 3.3V, 2.5V, 1.8V power supply. • Auto refresh and self refresh. • All inputs and outputs referenced to the positive edge of the system clock. • All pins are compatible with LVCMOS interface. • Data mask function by DQM. • 4K refresh cycle / 64ms. • Internal dual banks operation. • Programmable Burst Length and Burst Type. • Burst Read Single Write operation. - 1, 2, 4, 8 or Full Page for Sequential Burst. - 4 or 8 for Interleave Burst. • Programmable CAS Latency : 2,3 clocks. • Programmable Driver Strength Control - Full Strength or 1/2, 1/4, 1/8 of Full Strength • Special Function Support. - PASR(Partial Array Self Refresh) - Auto TCSR(Temperature Compensated Self Refresh) • Automatic precharge, includes CONCURRENT Auto Precharge Mode and controlled Precharge. • Deep Power Down Mode. Copyright © 2010 Integrated Silicon Solution, Inc. All rights reserved. ISSI reserves the right to make changes to this specification and its products at any time without notice. ISSI assumes no liability arising out of the application or use of any information, products or services described herein. Customers are advised to obtain the latest version of this device specification before relying on any published information and before placing orders for products. Integrated Silicon Solution, Inc. does not recommend the use of any of its products in life support applications where the failure or malfunction of the product can reasonably be expected to cause failure of the life support system or to significantly affect its safety or effectiveness. Products are not authorized for use in such applications unless Integrated Silicon Solution, Inc. receives written assurance to its satisfaction, that: a.) the risk of injury or damage has been minimized; b.) the user assume all such risks; and c.) potential liability of Integrated Silicon Solution, Inc is adequately protected under the circumstances Rev. A | Mar. 2011 www.issi.com - [email protected] 1 IS42SM/RM/VM16200C Figure1: 54Ball FBGA Ball Assignment 1 2 3 4 5 6 7 8 9 A VSS DQ15 VSSQ VDDQ DQ0 VDD B DQ14 DQ13 VDDQ VSSQ DQ2 DQ1 C DQ12 DQ11 VSSQ VDDQ DQ4 DQ3 D DQ10 DQ9 VDDQ VSSQ DQ6 DQ5 E DQ8 NC VSS VDD LDQM DQ7 F UDQM CLK CKE /CAS /RAS /WE G NC NC A9 BA NC /CS A8 A7 A6 A0 A1 A10 VSS A5 A4 A3 A2 VDD H J [Top View] Rev. A | Mar. 2011 www.issi.com - [email protected] 2 IS42SM/RM/VM16200C Table2: Pin Descriptions Pin Pin Name Descriptions CLK System Clock The system clock input. All other inputs are registered to the SDRAM on the rising edge CLK. CKE Clock Enable Controls internal clock signal and when deactivated, the SDRAM will be one of the states among power down, suspend or self refresh. /CS Chip Select Enable or disable all inputs except CLK, CKE and DQM. BA Bank Address Selects bank to be activated during RAS activity. Selects bank to be read/written during CAS activity. A0~A10 Address Row Address Column Address Auto Precharge /RAS, /CAS, /WE Row Address Strobe, Column Address Strobe, Write Enable RAS, CAS and WE define the operation. Refer function truth table for details. LDQM,UDQM Data Input/Output Mask Controls output buffers in read mode and masks input data in write mode. DQ0~DQ15 Data Input/Output Data input/output pin. VDD/VSS Power Supply/Ground Power supply for internal circuits and input buffers. VDDQ/VSSQ Data Output Power/Ground Power supply for output buffers. NC No Connection No connection. Rev. A | Mar. 2011 www.issi.com - [email protected] : RA0~RA10 : CA0~CA8 : A10 3 IS42SM/RM/VM16200C Figure2: Functional Block Diagram EXTENDED MODE REGISTER CLK CLOCK GENERATOR CKE TCSR PASR ADDRESS ROW DECODER ROW DECODER MODE REGISTER ROW ADDRESS BUFFER & REFRESH COUNTER BANK B BANK A SENSE AMPLIFIER /CAS /WE CONTROL LOGIC /RAS COMMAND DECODER /CS COLUMN DECODER & LATCH CIRCUIT COLUMN ADDRESS BUFFER & BURST COUNTER DATA CONTROL CIRCUIT DQM LATCH CIRCUIT INPUT & OUTPUT BUFFER DQ Rev. A | Mar. 2011 www.issi.com - [email protected] 4 IS42SM/RM/VM16200C Figure3: Simplified State Diagram EXTENDED MODE REGISTER SET MODE REGISTER SET SELF REFRESH MRS ACT DEEP POWER DOWN POWER DOWN ROW ACTIVE WRITE A SUSPEND CKE ↓ CKE CKE ↓ ACTIVE POWER DOWN READ PRE WRITE WRITE SUSPEND CBR REFRESH REF IDLE CKE ↓ READ WRITE READ WRITE CKE CKE CKE ↓ CKE ↓ WRITE A READ A CKE POWER ON CKE PRECHARGE READ SUSPEND READ A SUSPEND PRECHARGE Automatic Sequence Manual Input Rev. A | Mar. 2011 www.issi.com - [email protected] 5 IS42SM/RM/VM16200C Figure4: Mode Register Definition BA A10 A9 A8 A7 A6 A5 A4 A3 A2 A1 A0 Address Bus 11 0 10 9 8 WB 0 7 0 6 5 4 CAS Latency 0 3 BT 2 1 0 Mode Register (Mx) Burst Length M9 Write Burst Mode M6 M5 M4 CAS Latency M3 Burst Type 0 Burst Read and Burst Write 0 0 0 Reserved 0 Sequential 1 Burst Read and Single Write 0 0 1 - 1 Interleave 0 1 0 0 1 1 M2 M1 M0 0 0 2 0 1 3 0 0 1 0 1 1 Burst Length M3 = 0 M3 = 1 0 1 1 0 1 2 2 0 1 0 4 4 Reserved 0 1 1 8 8 1 Reserved 1 0 0 Reserved Reserved 1 0 Reserved 1 0 1 Reserved Reserved 1 1 Reserved 1 1 0 Reserved Reserved 1 1 1 Full Page Reserved Note: M11(BA) must be set to “0” to select Mode Register (vs. the Extended Mode Register) Burst Type Accesses within a given burst may be programmed to be either sequential or interleaved; this is referred to as the burst type and is selected via bit M3. The ordering of accesses within a burst is determined by the burst length, the burst type and the starting column address, as shown in Table 3. Table 3: Burst Definition Burst Length Starting Column Order of Access Within a Burst Address Sequential Interleaved A2 A1 A0 2 4 8 Full Page 0 0-1 0-1 1 1-0 1-0 0 0 0-1-2-3 0-1-2-3 0 1 1-2-3-0 1-0-3-2 1 0 2-3-0-1 2-3-0-1 1 1 3-0-1-2 3-2-1-0 0 0 0 0-1-2-3-4-5-6-7 0-1-2-3-4-5-6-7 0 0 1 1-2-3-4-5-6-7-0 1-0-3-2-5-4-7-6 0 1 0 2-3-4-5-6-7-0-1 2-3-0-1-6-7-4-5 0 1 1 3-4-5-6-7-0-1-2 3-2-1-0-7-6-5-4 1 0 0 4-5-6-7-0-1-2-3 4-5-6-7-0-1-2-3 1 0 1 5-6-7-0-1-2-3-4 5-4-7-6-1-0-3-2 1 1 0 6-7-0-1-2-3-4-5 6-7-4-5-2-3-0-1 1 1 1 7-0-1-2-3-4-5-6 7-6-5-4-3-2-1-0 n=A0-8 (Location 0-511) Cn, Cn+1. Cn+2, Cn+3, Cn+4… …Cn-1, Cn... Not Supported Rev. A | Mar. 2011 Note : 1. For full-page accesses: y = 512 2. For a burst length of two, A1-A8 select the blockof-two burst; A0 selects the starting column within the block. 3. For a burst length of four, A2-A8 select the blockof-four burst; A0-A1 select the starting column within the block. 4. For a burst length of eight, A3-A8 select the block-of-eight burst; A0-A2 select the starting column within the block. 5. For a full-page burst, the full row is selected and A0-A8 select the starting column. 6. Whenever a boundary of the block is reached within a given sequence above, the following access wraps within the block. 7. For a burst length of one, A0-A8 select the unique column to be accessed, and mode register bit M3 is ignored. www.issi.com - [email protected] 6 IS42SM/RM/VM16200C Figure5: Extended Mode Register BA A10 A9 A8 A7 A6 A5 A4 A3 A2 A1 A0 Address Bus 11 1 10 0 9 0 E6 E5 Driver Strength 0 0 Full Strength 0 1 1/2 Strength 1 0 1/4 Strength 1 1 1/8 Strength 8 0 7 6 0 5 4 3 2 TCSR DS 1 PASR 0 Extended Mode Register (Ex) E4 E3 Maximum Case Temp. 0 0 85° 0 1 70° 1 0 45° 1 1 Auto E2 E1 E0 0 0 0 All Banks 0 0 1 One Bank (BA=0) 0 1 0 Reserved 0 1 1 Reserved 1 0 0 Reserved 1 0 1 Half of One Bank (BA=0, Row Address MSB=0) 1 1 0 Quarter of One Bank (BA=0, Row Address 2 MSB=0) 1 1 1 Reserved Self Refresh Coverage Note: E11(BA) must be set to “1” to select Extend Mode Register (vs. the base Mode Register) Rev. A | Mar. 2011 www.issi.com - [email protected] 7 IS42SM/RM/VM16200C Functional Description In general, this 32Mb SDRAM (1M x 16Bits x 2banks) is a dual-bank DRAM that operates at 3.0V/3.3V and includes a synchronous interface (all signals are registered on the positive edge of the clock signal, CLK). Each of the 16,777,216-bit banks is organized as 2,048 rows by 512 columns by 16-bits Read and write accesses to the SDRAM are burst oriented; accesses start at a selected location and continue for a programmed number of locations in a programmed sequence. Accesses begin with the registration of an ACTIVE command, which is then followed by a READ or WRITE command. The address bits registered coincident with the ACTIVE command are used to select the bank and row to be accessed (BA select the bank, A0-A10 select the row). The address bits (BA select the bank, A0-A8 select the column) registered coincident with the READ or WRITE command are used to select the starting column location for the burst access. Prior to normal operation, the SDRAM must be initialized. The following sections provide detailed information covering device initialization, register definition, command descriptions and device operation. Power up and Initialization SDRAMs must be powered up and initialized in a predefined manner. Operational procedures other than those specified may result in undefined operation. Once power is applied to VDD and VDDQ(simultaneously) and the clock is stable(stable clock is defined as a signal cycling within timing constraints specified for the clock pin), the SDRAM requires a 100µs delay prior to issuing any command other than a COMMAND INHIBIT or NOP. CKE must be held high during the entire initialization period until the PRECHARGE command has been issued. Starting at some point during this 100µs period and continuing at least through the end of this period, COMMAND INHIBIT or NOP commands should be applied. Once the 100µs delay has been satisfied with at least one COMMAND INHIBIT or NOP command having been applied, a PRECHARGE command should be applied. All banks must then be precharged, thereby placing the device in the all banks idle state. Once in the idle state, two AUTO REFRESH cycles must be performed. After the AUTO REFRESH cycles are complete, the SDRAM is ready for mode register programming. Because the mode register will power up in an unknown state, it should be loaded prior to applying any operational command. And a extended mode register set command will be issued to program specific mode of self refresh operation(PASR). The following these cycles, the Low Power SDRAM is ready for normal operation. Register Definition Mode Register The mode register is used to define the specific mode of operation of the SDRAM. This definition includes the selection of a burst length, a burst type, a CAS latency, an operating mode and a write burst mode. The mode register is programmed via the LOAD MODE REGISTER command and will retain the stored information until it is programmed again or the device loses power. Mode register bits M0-M2 specify the burst length, M3 specifies the type of burst (sequential or interleaved), M4-M6 specify the CAS latency, M7 and M8 specify the operating mode, M9 specifies the write burst mode, and M10 should be set to zero. M11 should be set to zero to prevent extended mode register. The mode register must be loaded when all banks are idle, and the controller must wait the specified time before initiating the subsequent operation. Violating either of these requirements will result in unspecified operation. Extended Mode Register The Extended Mode Register controls the functions beyond those controlled by the Mode Register. These additional functions are special features of the BATRAM device. They include Temperature Compensated Self Refresh (TCSR) Control, and Partial Array Self Refresh (PASR) and Driver Strength (DS). The Extended Mode Register is programmed via the Mode Register Set command (BA=1) and retains the stored information until it is programmed again or the device loses power. The Extended Mode Register must be programmed with M7 through M10 set to “0”. The Extended Mode Register must be loaded when all banks are idle and no bursts are in progress, and the controller must wait the specified time before initiating any subsequent operation. Violating either of these requirements results in unspecified operation. Rev. A | Mar. 2011 www.issi.com - [email protected] 8 IS42SM/RM/VM16200C Burst Length Read and write accesses to the SDRAM are burst oriented, with the burst length being programmable, as shown in Figure 4. The burst length determines the maximum number of column locations that can be accessed for a given READ or WRITE command. Burst lengths of 1, 2, 4 or 8 locations are available for both the sequential and the interleaved burst types, and a full-page burst is available for the sequential type. The full-page burst is used in conjunction with the BURST TERMINATE command to generate arbitrary burst lengths. Reserved states should not be used, as unknown operation or incompatibility with future versions may result. When a READ or WRITE command is issued, a block of columns equal to the burst length is effectively selected. All accesses for that burst take place within this block, meaning that the burst will wrap within the block if a boundary is reached. The block is uniquely selected by A1-A8 when the burst length is set to two; by A2-A8 when the burst length is set to four; and by A3-A8 when the burst length is set to eight. The remaining (least significant) address bit(s) is (are) used to select the starting location within the block. Full-page bursts wrap within the page if the boundary is reached. Bank(Row) Active The Bank Active command is used to activate a row in a specified bank of the device. This command is initiated by activating CS, RAS and deasserting CAS, WE at the positive edge of the clock. The value on the BA selects the bank, and the value on the A0-A10 selects the row. This row remains active for column access until a precharge command is issued to that bank. Read and write operations can only be initiated on this activated bank after the minimum tRCD time is passed from the activate command. Read The READ command is used to initiate the burst read of data. This command is initiated by activating CS, CAS, and deasserting WE, RAS at the positive edge of the clock. BA input select the bank, A0-A8 address inputs select the starting column location. The value on input A10 determines whether or not Auto Precharge is used. If Auto Precharge is selected the row being accessed will be precharged at the end of the READ burst; if Auto Precharge is not selected, the row will remain active for subsequent accesses. The length of burst and the CAS latency will be determined by the values programmed during the MRS command. Write The WRITE command is used to initiate the burst write of data. This command is initiated by activating CS, CAS, WE and deasserting RAS at the positive edge of the clock. BA input select the bank, A0-A8 address inputs select the starting column location. The value on input A10 determines whether or not Auto Precharge is used. If Auto Precharge is selected the row being accessed will be precharged at the end of the WRITE burst; if Auto Precharge is not selected, the row will remain active for subsequent accesses. Rev. A | Mar. 2011 www.issi.com - [email protected] 9 IS42SM/RM/VM16200C CAS Latency The CAS latency is the delay, in clock cycles, between the registration of a READ command and the availability of the first piece of output data. The latency can be set to two or three clocks. If a READ command is registered at clock edge n, and the latency is m clocks, the data will be available by clock edge n + m. The DQs will start driving as a result of the clock edge one cycle earlier (n + m 1), and provided that the relevant access times are met, the data will be valid by clock edge n + m. For example, assuming that the clock cycle time is such that all relevant access times are met, if a READ command is registered at T0 and the latency is programmed to two clocks, the DQs will start driving after T1 and the data will be valid by T2, as shown in Figure 6. Reserved states should not be used as unknown operation or incompatibility with future versions may result. Figure6: CAS Latency T0 T1 T3 T2 CLK COMMAND NOP READ NOP tOH tLZ DQ Dout tAC CAS Latency=2 T0 T1 T2 T3 T4 CLK COMMAND READ NOP NOP tLZ DQ NOP tOH Dout tAC CAS Latency=3 DON’T CARE UNDEFINED Operating Mode The normal operating mode is selected by setting M7 and M8 to zero; the other combinations of values for M7 and M8 are reserved for future use and/or test modes. The programmed burst length applies to both READ and WRITE bursts. Test modes and reserved states should not be used because unknown operation or incompatibility with future versions may result. Write Burst Mode When M9 = 0, the burst length programmed via M0-M2 applies to both READ and WRITE bursts; when M9 = 1, the programmed burst length applies to READ bursts, but write accesses are single-location (nonburst) accesses. Rev. A | Mar. 2011 www.issi.com - [email protected] 10 IS42SM/RM/VM16200C Table4: Command Truth Table Function CKEn-1 CKEn /CS /RAS /CAS /WE DQM Command Inhinit (NOP) H X H X X X X X No Operation (NOP) H X L H H H X X Mode Register Set H X L L L L X OP CODE 4 Extended Mode Register Set H X L L L L X OP CODE 4 Active (select bank and activate row) H X L L H H X Bank/Row Read H X L H L H L/H Bank/Col L 5 Read with Autoprecharge H X L H L H L/H Bank/Col H 5 Write H X L H L L L/H Bank/Col L 5 Write with Autoprecharge H X L H L L L/H Bank/Col H 5 Precharge All Banks H X L L H L X X H Precharge Selected Bank H X L L H L X Bank L Burst Stop H H L H H L X X Auto Refresh H H L L L H X X 3 Self Refresh Entry H L L L L H X X 3 Self Refresh Exit L H H X X X L H H H X X 2 Precharge Power Down Entry H L H X X X L H H H X X Precharge Down Exit L H H X X X L H H H X X Clock Suspend Entry H L H X X X L V V V X X Clock Suspend Exit L H X X Deep Power Down Entry H L X X Deep Power Down Exit L H X X X L H H X L ADDR A10 Note 6 Note : 1. CKEn is the logic state of CKE at clock edge n; CKEn-1 was the state of CKE at the previous clock edge. H: High Level, L: Low Level, X: Don't Care, V: Valid 2. Exiting Self Refresh occurs by asynchronously bringing CKE from low to high and will put the device in the all banks idle state once tXSR is met. Command Inhibit or NOP commands should be issued on any clock edges occuring during the tXSR period. A minimum of two NOP commands must be provided during tXSR period. 3. During refresh operation, internal refresh counter controls row addressing; all inputs and I/Os are “Don’t Care” except for CKE. 4. A0-A10 define OP CODE written to the mode register, and BA must be issued 0 in the mode register set, and 1 in the extended mode register set. 5. DQM “L” means the data Write/Ouput Enable and “H” means the Write inhibit/Output High-Z. Write DQM Latency is 0 CLK and Read DQM Latency is 2 CLK. 6. Standard SDRAM parts assign this command sequence as Burst Terminate. For Bat Ram parts, the Burst Terminate command is assigned to the Deep Power Down function. Rev. A | Mar. 2011 www.issi.com - [email protected] 11 IS42SM/RM/VM16200C Table5: Function Truth Table Current State Idle Row Active Read Command Action Note Mode Register Set Set the Mode Register 14 X Auto or Self Refresh Start Auto or Self Refresh 5 BA X Precharge No Operation H BA Row Add. Bank Activate Activate the Specified Bank and Row L L BA Col Add./ A10 Write/WriteAP ILLEGAL 4 H L H BA Col Add./ A10 Read/ReadAP ILLEGAL 4 L H H H X X No Operation No Operation 3 H X X X X X Device Deselect No Operation or Power Down 3 L L L L Mode Register Set ILLEGAL 13,14 L L L H X X Auto or Self Refresh ILLEGAL 13 L L H L BA X Precharge Precharge 7 L L H H BA Row Add. Bank Activate ILLEGAL 4 L H L L BA Col Add./A10 Write/Write AP Start Write : Optional AP(A10=H) 6 L H L H BA Col Add./A10 Read/Read AP Start Read : Optional AP(A10=H) 6 L H H H X X No Operation No Operation H X X X X X Device Deselect No Operation L L L L Mode Register Set ILLEGAL 13,14 L L L H X X Auto or Self Refresh ILLEGAL 13 L L H L BA X Precharge Termination Burst : Start the Precharge L L H H BA Row Add. Bank Activate ILLEGAL L H L L BA Col Add./A10 Write/WriteAP Termination Burst : Start Write(AP) 8,9 L H L H BA Col Add./A10 Read/Read AP Terimination Burst : Start Read(AP) 8 L H H H X X No Operation Continue the Burst H X X X X X Device Deselect Continue the Burst /CS /RAS /CAS /WE L L L L L L L H X L L H L L L H L H L Rev. A | Mar. 2011 BA A0-A10 OP CODE OP CODE OP CODE Description www.issi.com - [email protected] 4 12 IS42SM/RM/VM16200C Table5: Function Truth Table Current State Command /CS /RAS /CAS /WE L L L L L L L H X L L H L L L H L H L Write Read with Auto Precharge Write with Auto Precharge Rev. A | Mar. 2011 BA A0-A10 OP CODE Description Action Note Mode Register Set ILLEGAL 13,14 X Auto or Self Refresh ILLEGAL 13 BA X Precharge Termination Burst : Start the Precharge 10 H BA Row Add. Bank Activate ILLEGAL 4 L L BA Col Add./A10 Write/WriteAP Termination Burst : Start Write(AP) 8 H L H BA Col Add./A10 Read/ReadAP Terimination Burst : Start READ(AP) 8,9 L H H H X X No Operation Continue the Burst H X X X X X Device Deselect Continue the Burst L L L L Mode Register Set ILLEGAL 13,14 L L L H X X Auto or Self Refresh ILLEGAL 13 L L H L BA X Precharge ILLEGAL 4,12 L L H H BA Row Add. Bank Activate ILLEGAL 4,12 L H L L BA Col Add./A10 Write/WriteAP ILLEGAL 12 L H L H BA Col Add./A10 Read/ReadAP ILLEGAL 12 L H H H X X No Operation Continue the Burst H X X X X X Device Deselect Continue the Burst L L L L Mode Register Set ILLEGAL 13,14 L L L H X X Auto or Self Refresh ILLEGAL 13 L L H L BA X Precharge ILLEGAL 4,12 L L H H BA Row Add. Bank Activate ILLEGAL 4,12 L H L L BA Col Add./A10 Write/WriteAP ILLEGAL 12 L H L H BA Col Add./A10 Read/ReadAP ILLEGAL 12 L H H H X X No Operation Continue the Burst H X X X X X Device Deselect Continue the Burst OP CODE OP CODE www.issi.com - [email protected] 13 IS42SM/RM/VM16200C Table5: Function Truth Table Current State Command /CS /RAS /CAS /WE L L L L L L L H X L L H L L L H L H L Precharging Row Activating Write Recovering Rev. A | Mar. 2011 BA A0-A10 OP CODE Description Action Note Mode Register Set ILLEGAL 13,14 X Auto or Self Refresh ILLEGAL 13 BA X Precharge No Operation : Bank(s) Idle after tRP H BA Row Add. Bank Activate ILLEGAL 4,12 L L BA Col Add./ A10 Write/WriteAP ILLEGAL 4,12 H L H BA Col Add./ A10 Read/ReadAP ILLEGAL 4,12 L H H H X X No Operation No Operation : Bank(s) Idle after tRP H X X X X X Device Deselect No Operation : Bank(s) Idle after tRP L L L L Mode Register Set ILLEGAL 13,14 L L L H X X Auto or Self Refresh ILLEGAL 13 L L H L BA X Precharge ILLEGAL 4,12 L L H H BA Row Add. Bank Activate ILLEGAL 4,11,12 L H L L BA Col Add./A10 Write/Write AP ILLEGAL 4,12 L H L H BA Col Add./A10 Read/Read AP ILLEGAL 4,12 L H H H X X No Operation No Operation : ROw Active after tRCD H X X X X X Device Deselect No Operation : ROw Active after tRCD L L L L Mode Register Set ILLEGAL 13,14 L L L H X X Auto or Self Refresh ILLEGAL 13 L L H L BA X Precharge ILLEGAL 4,13 L L H H BA Row Add. Bank Activate ILLEGAL 4,12 L H L L BA Col Add./A10 Write/WriteAP Start Write : Optional AP(A10=H) L H L H BA Col Add./A10 Read/Read AP Start Write : Optional AP(A10=H) L H H H X X No Operation No Operation : Row Active after tDPL H X X X X X Device Deselect No Operation : Row Active after tDPL OP CODE OP CODE www.issi.com - [email protected] 9 14 IS42SM/RM/VM16200C Table5: Function Truth Table Current State Command /CS /RAS /CAS /WE L L L L L L L H X L L H L L L H L H L Write Recovering with Auto Precharge Refreshing Mode Register Accessing Rev. A | Mar. 2011 BA A0-A10 OP CODE Description Action Note Mode Register Set ILLEGAL 13,14 X Auto or Self Refresh ILLEGAL 13 BA X Precharge ILLEGAL 4,13 H BA Row Add. Bank Activate ILLEGAL 4,12 L L BA Col Add./ A10 Write/WriteAP ILLEGAL 4,12 H L H BA Col Add./ A10 Read/ReadAP ILLEGAL 4,9,12 L H H H X X No Operation No Operation : Precharge after tDPL H X X X X X Device Deselect No Operation : Precharge after tDPL L L L L Mode Register Set ILLEGAL 13,14 L L L H X X Auto or Self Refresh ILLEGAL 13 L L H L BA X Precharge ILLEGAL 13 L L H H BA Row Add. Bank Activate ILLEGAL 13 L H L L BA Col Add./A10 Write/Write AP ILLEGAL 13 L H L H BA Col Add./A10 Read/Read AP ILLEGAL 13 L H H H X X No Operation No Operation : Idle after tRC H X X X X X Device Deselect No Operation : Idle after tRC L L L L Mode Register Set ILLEGAL 13,14 L L L H X X Auto or Self Refresh ILLEGAL 13 L L H L BA X Precharge ILLEGAL 13 L L H H BA Row Add. Bank Activate ILLEGAL 13 L H L L BA Col Add./A10 Write/WriteAP ILLEGAL 13 L H L H BA Col Add./A10 Read/Read AP ILLEGAL 13 L H H H X X No Operation No Operation : Idle after 2 Clock Cycle H X X X X X Device Deselect No Operation : Idle after 2 Clock Cycle OP CODE OP CODE www.issi.com - [email protected] 15 IS42SM/RM/VM16200C Note : 1. H: Logic High, L: Logic Low, X: Don't care, BA: Bank Address, AP: Auto Precharge. 2. All entries assume that CKE was active during the preceding clock cycle. 3. If both banks are idle and CKE is inactive, then in power down cycle 4. Illegal to bank in specified states. Function may be legal in the bank indicated by Bank Address, depending on the state of that bank. 5. If both banks are idle and CKE is inactive, then Self Refresh mode. 6. Illegal if tRCD is not satisfied. 7. Illegal if tRAS is not satisfied. 8. Must satisfy burst interrupt condition. 9. Must satisfy bus contention, bus turn around, and/or write recovery requirements. 10. Must mask preceding data which don't satisfy tDPL. 11. Illegal if tRRD is not satisfied 12. Illegal for single bank, but legal for other banks in multi-bank devices. 13. Illegal for all banks. 14. Mode Register Set and Extended Mode Register Set is same command truth table except BA. Rev. A | Mar. 2011 www.issi.com - [email protected] 16 IS42SM/RM/VM16200C Table6: CKE Truth Table Current State Self Refresh CKE Command /CS /RAS /CAS /WE BA A0-A10 H X X X X X X X INVALID 2 L H H X X X X X Exit Self Refresh with Device Deselect 3 L H L H H H X X Exit Self Refresh with No Operation 3 L H L H H L X X ILLEGAL 3 L H L H L X X X ILLEGAL 3 L H L L X X X X ILLEGAL 3 L L X X X X X X Maintain Self Refresh H X X X X X X X INVALID 2 L H H X X X X X L H H H X X Power Down Mode Exit, All Banks Idle 3 L X X X X X L X X X X X L X X L All Banks Idle Any State other than listed above Note Current Cycle Power Down Deep Power Down Action Prev Cycle H L ILLEGAL 3 L L X X X X X X Maintain Power Down Mode H X X X X X X X INVALID 2 L H X X X X X X Deep Power Down Mode Exit 6 L L X X X X X X Maintain Deep Power Down Mode H H H X X X H H L H X X H H L L H X H H L L L H H H L L L L H L H X X X H L L H X X H L L L H X H L L L L H H L L L L L L X X X X X X X Power Down H H X X X X X X Refer to Operations of the Current State Truth Table H L X X X X X X Begin Clock Suspend next cycle L H X X X X X X Exit Clock Suspend next cycle L L X X X X X X Maintain Clock Suspend Rev. A | Mar. 2011 Refer to the Idle State section of the Current State Truth Table 4 4 4 X X OP CODE Auto Refresh Mode Register Set 5 Refer to the Idle State section of the Current State Truth Table 4 4 4 X X Entry Self Refresh OP CODE Mode Register Set www.issi.com - [email protected] 5 5 17 IS42SM/RM/VM16200C Note : 1. H: Logic High, L: Logic Low, X: Don't care 2. For the given current state CKE must be low in the previous cycle. 3. When CKE has a low to high transition, the clock and other inputs are re-enabled asynchronously. When exiting power down mode, a NOP (or Device Deselect) command is required on the first positive edge of clock after CKE goes high. 4. The address inputs depend on the command that is issued. 5. The Precharge Power Down mode, the Self Refresh mode, and the Mode Register Set can only be entered from the all banks idle state. 6. When CKE has a low to high transition, the clock and other inputs are re-enabled asynchronously. When exiting deep power down mode, a NOP (or Device Deselect) command is required on the first positive edge of clock after CKE goes high and is maintained for a minimum 100usec. Rev. A | Mar. 2011 www.issi.com - [email protected] 18 IS42SM/RM/VM16200C Table7A: 3.3V Absolute Maximum Rating Parameter Symbol Ambient Temperature (Industrial) Rating -40 ~ 85 TA Ambient Temperature (Commercial) Unit °C 0 ~ 70 TSTG -55 ~ 150 °C VIN, VOUT -1.0 ~ 4.6 V VDD, VDDQ -1.0 ~ 4.6 V Short Circuit Output Current IOS 50 mA Power Dissipation PD 1 W Storage Temperature Voltage on Any Pin relative to VSS Voltage on VDD relative to VSS Note : Stresses greater than those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress rating only, and functional operation of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect reliability. Table8A: 3.3V Capacitance (TA=25 °C, f=1MHz, VDD=3.3V) Parameter Input Capacitance Pin Symbol Min Max Unit CLK CI1 2 4 pF A0~A10, BA, CKE, /CS, /RAS, /CAS, /WE, L(U)DQM CI2 2 4 pF DQ0~DQ15 CIO 3 5 pF Data Input/Output Capacitance Table9A: 3.3V DC Operating Condition (Voltage referenced to VSS=0V, TA= -40 ~ 85 °C) Parameter Symbol Min Typ Max Unit VDD 2.7 3.3 3.6 V VDDQ 2.7 3.3 3.6 V 1 Input High Voltage VIH 2.2 - VDDQ+0.3 V 2 Input Low Voltage VIL -0.3 0 0.5 V 3 Output High Voltage VOH 2.4 - - V IOH= -0.1mA Output Low Voltage VOL - - 0.4 V IOL= +0.1mA Input Leakage Current ILI -1 - 1 uA 4 Output Leakage Current ILO -1.5 1.5 uA 5 Power Supply Voltage Note Note : 1. VDDQ must not exceed the level of VDD 2. VIH(max) = 5.3V AC. The overshoot voltage duration is ≤ 3ns. 3. VIL(min) = -2.0V AC. The overshoot voltage duration is ≤ 3ns. 4. Any input 0V ≤ VIN ≤ VDDQ. Input leakage currents include Hi-Z output leakage for all bi-directional buffers with tri-state outputs. 5. DOUT is disabled, 0V ≤ VOUT ≤ VDDQ. Rev. A | Mar. 2011 www.issi.com - [email protected] 19 IS42SM/RM/VM16200C Table10A: 3.3V AC Operating Condition (TA= -40 ~ 85 °C, VDD = 2.7V-3.6V, VSS=0V) Parameter Symbol Value Unit VIH / VIL 2.4 / 0.4 V Input Timing Measurement Reference Level Voltage VTRIP 0.5 x VDDQ V Input Rise / Fall Time tR / tF 1/1 ns VOUTREF 0.5 x VDDQ V CL 30 pF AC Input High/Low Level Voltage Output Timing Measurement Reference Level Voltage Output Load Capacitance for Access Time Measurement VTT=0.5 x VDDQ VDDQ 1200Ω Output 50Ω Output 870Ω 30pF 30pF DC Output Load Circuit Rev. A | Mar. 2011 Z0=50Ω AC Output Load Circuit www.issi.com - [email protected] 20 IS42SM/RM/VM16200C Table7B: 2.5V Absolute Maximum Rating Parameter Symbol Ambient Temperature (Industrial) Rating -40 ~ 85 TA Ambient Temperature (Commercial) Unit °C 0 ~ 70 TSTG -55 ~ 150 °C VIN, VOUT -1.0 ~ 3.6 V VDD, VDDQ -1.0 ~ 3.6 V Short Circuit Output Current IOS 50 mA Power Dissipation PD 1 W Storage Temperature Voltage on Any Pin relative to VSS Voltage on VDD relative to VSS Note : Stresses greater than those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress rating only, and functional operation of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect reliability. Table8B: 2.5V Capacitance (TA=25 °C, f=1MHz, VDD=2.5V) Parameter Input Capacitance Pin Symbol Min Max Unit CLK CI1 2 4 pF A0~A10, BA, CKE, /CS, /RAS, /CAS, /WE, L(U)DQM CI2 2 4 pF DQ0~DQ15 CIO 3 5 pF Data Input/Output Capacitance Table9B: 2.5V DC Operating Condition (Voltage referenced to VSS=0V, TA= -40 ~ 85 °C) Parameter Symbol Min Typ Max Unit VDD 2.3 2.5 3.0 V VDDQ 2.3 2.5 3.0 V 1 Input High Voltage VIH 0.8 x VDDQ - VDDQ+0.3 V 2 Input Low Voltage VIL -0.3 0 0.3 V 3 Output High Voltage VOH 0.9 x VDDQ - - V IOH= -0.1mA Output Low Voltage VOL - - 0.2 V IOL= +0.1mA Input Leakage Current ILI -1 - 1 uA 4 Output Leakage Current ILO -1.5 1.5 uA 5 Power Supply Voltage Note Note : 1. VDDQ must not exceed the level of VDD 2. VIH(max) = VDDQ+1.5V AC. The overshoot voltage duration is ≤ 3ns. 3. VIL(min) = -1.0V AC. The overshoot voltage duration is ≤ 3ns. 4. Any input 0V ≤ VIN ≤ VDDQ. Input leakage currents include Hi-Z output leakage for all bi-directional buffers with tri-state outputs. 5. DOUT is disabled, 0V ≤ VOUT ≤ VDDQ. Rev. A | Mar. 2011 www.issi.com - [email protected] 21 IS42SM/RM/VM16200C Table10B: 2.5V AC Operating Condition (TA= -40 ~ 85 °C, VDD = 2.3V-3.0V, VSS=0V) Parameter Symbol Value Unit VIH / VIL 0.9 x VDDQ / 0.2 V Input Timing Measurement Reference Level Voltage VTRIP 0.5 x VDDQ V Input Rise / Fall Time tR / tF 1/1 ns VOUTREF 0.5 x VDDQ V CL 30 pF AC Input High/Low Level Voltage Output Timing Measurement Reference Level Voltage Output Load Capacitance for Access Time Measurement VTT=0.5 x VDDQ VDDQ 500Ω Output 50Ω Output 500Ω 30pF 30pF DC Output Load Circuit Rev. A | Mar. 2011 Z0=50Ω AC Output Load Circuit www.issi.com - [email protected] 22 IS42SM/RM/VM16200C Table7C: 1.8V Absolute Maximum Rating Parameter Symbol Ambient Temperature (Industrial) Rating -40 ~ 85 TA Ambient Temperature (Commercial) Unit °C 0 ~ 70 TSTG -55 ~ 150 °C VIN, VOUT -1.0 ~ 2.6 V VDD, VDDQ -1.0 ~ 2.6 V Short Circuit Output Current IOS 50 mA Power Dissipation PD 1 W Storage Temperature Voltage on Any Pin relative to VSS Voltage on VDD relative to VSS Note : Stresses greater than those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress rating only, and functional operation of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect reliability. Table8C: 1.8V Capacitance (TA=25 °C, f=1MHz, VDD=1.8V) Parameter Input Capacitance Pin Symbol Min Max Unit CLK CI1 2 4 pF A0~A10, BA, CKE, /CS, /RAS, /CAS, /WE, L(U)DQM CI2 2 4 pF DQ0~DQ15 CIO 3 5 pF Data Input/Output Capacitance Table9C: 1.8V DC Operating Condition (Voltage referenced to VSS=0V, TA= -40 ~ 85 °C) Parameter Symbol Min Typ Max Unit VDD 1.7 1.8 1.95 V VDDQ 1.7 1.8 1.95 V 1 Input High Voltage VIH 0.8 x VDDQ - VDDQ+0.3 V 2 Input Low Voltage VIL -0.3 0 0.3 V 3 Output High Voltage VOH 0.9 x VDDQ - - V IOH= -0.1mA Output Low Voltage VOL - - 0.2 V IOL= +0.1mA Input Leakage Current ILI -1 - 1 uA 4 Output Leakage Current ILO -1.5 1.5 uA 5 Power Supply Voltage Note Note : 1. VDDQ must not exceed the level of VDD 2. VIH(max) = VDDQ+1.5V AC. The overshoot voltage duration is ≤ 3ns. 3. VIL(min) = -1.0V AC. The overshoot voltage duration is ≤ 3ns. 4. Any input 0V ≤ VIN ≤ VDDQ. Input leakage currents include Hi-Z output leakage for all bi-directional buffers with tri-state outputs. 5. DOUT is disabled, 0V ≤ VOUT ≤ VDDQ. Rev. A | Mar. 2011 www.issi.com - [email protected] 23 IS42SM/RM/VM16200C Table10C: 1.8V AC Operating Condition (TA= -40 ~ 85 °C, VDD = 1.7V-1.95V, VSS=0V) Parameter Symbol Value Unit VIH / VIL 0.9 x VDDQ / 0.2 V Input Timing Measurement Reference Level Voltage VTRIP 0.5 x VDDQ V Input Rise / Fall Time tR / tF 1/1 ns VOUTREF 0.5 x VDDQ V CL 30 pF AC Input High/Low Level Voltage Output Timing Measurement Reference Level Voltage Output Load Capacitance for Access Time Measurement VTT=0.5 x VDDQ VDDQ 500Ω Output 50Ω Output 500Ω 30pF 30pF DC Output Load Circuit Rev. A | Mar. 2011 Z0=50Ω AC Output Load Circuit www.issi.com - [email protected] 24 IS42SM/RM/VM16200C Table11A: 3.3V DC Characteristic (DC operating conditions unless otherwise noted) Parameter Sym Test Condition Speed -60 -75 Operating Current ICC1 Burst Length=1, One Bank Active, tRC ≥ tRC(min) IOL = 0 mA 50 Precharge Standby Current in Power Down Mode ICC2P CKE ≤ VIL(max), tCK = 10ns 80 ICC2PS CKE & CLK ≤ VIL(max), tCK = ∞ 80 ICC2N CKE ≥ VIH(min), /CS ≥ VIH(min), tCK = 10ns Input signals are changed one time during 2 clks. 9 CKE ≥ VIH(min), CLK ≤ VIL(max), tCK = ∞ Input signals are stable. 5 Precharge Standby Current in Non Power Down Mode ICC2NS Active Standby Current in Power Down Mode Active Standby Current in Non Power Down Mode CKE ≤ VIL(max), tCK = 10ns 1.0 ICC3PS CKE & CLK ≤ VIL(max), tCK = ∞ 0.5 ICC3N CKE ≥ VIH(min), /CS ≥ VIH(min), tCK = 10ns Input signals are changed one time during 2 clks. 18 CKE ≥ VIH(min), CLK ≤ VIL(max), tCK = ∞ Input signals are stable. 10 Burst Mode Operating Current ICC4 tCK>tCK(min), IOL = 0 mA, Page Burst All Banks Activated, tCCD = 1 clk Auto Refresh Current (4K Cycle) ICC5 tRC ≥ tRFC(min), All Banks Active PASR Self Refresh Current 2 Banks 1 Bank Note mA 1 uA mA ICC3P ICC3NS Unit mA mA 60 55 40 mA 1 mA 2 TCSR 45~85°C -25~45°C 200 ICC6 CKE ≤ 0.2V 170 45~85°C 180 -25~45°C 150 Deep Power Down Mode Current ICC7 10 uA uA Note : 1. Measured with outputs open. 2. Refresh period is 64ms. Rev. A | Mar. 2011 www.issi.com - [email protected] 25 IS42SM/RM/VM16200C Table11B: 2.5V DC Characteristic (DC operating conditions unless otherwise noted) Parameter Sym Test Condition Speed -60 -75 Operating Current ICC1 Burst Length=1, One Bank Active, tRC ≥ tRC(min) IOL = 0 mA 50 Precharge Standby Current in Power Down Mode ICC2P CKE ≤ VIL(max), tCK = 10ns 80 ICC2PS CKE & CLK ≤ VIL(max), tCK = ∞ 80 ICC2N CKE ≥ VIH(min), /CS ≥ VIH(min), tCK = 10ns Input signals are changed one time during 2 clks. 9 CKE ≥ VIH(min), CLK ≤ VIL(max), tCK = ∞ Input signals are stable. 5 Precharge Standby Current in Non Power Down Mode ICC2NS Active Standby Current in Power Down Mode Active Standby Current in Non Power Down Mode CKE ≤ VIL(max), tCK = 10ns 1.0 ICC3PS CKE & CLK ≤ VIL(max), tCK = ∞ 0.5 ICC3N CKE ≥ VIH(min), /CS ≥ VIH(min), tCK = 10ns Input signals are changed one time during 2 clks. 18 CKE ≥ VIH(min), CLK ≤ VIL(max), tCK = ∞ Input signals are stable. 10 Burst Mode Operating Current ICC4 tCK>tCK(min), IOL = 0 mA, Page Burst All Banks Activated, tCCD = 1 clk Auto Refresh Current (4K Cycle) ICC5 tRC ≥ tRFC(min), All Banks Active Self Refresh Current PASR TCSR 2 Banks 45~85°C 1 Bank -25~45°C mA 1 uA mA mA 60 55 40 mA 1 mA 2 200 ICC6 CKE ≤ 0.2V 170 45~85°C 180 -25~45°C 150 Deep Power Down Mode Current Note mA ICC3P ICC3NS Unit ICC7 10 uA uA Note : 1. Measured with outputs open. 2. Refresh period is 64ms. Rev. A | Mar. 2011 www.issi.com - [email protected] 26 IS42SM/RM/VM16200C Table11C: 1.8V DC Characteristic (DC operating conditions unless otherwise noted) Parameter Sym Test Condition Speed -60 -75 Operating Current ICC1 Burst Length=1, One Bank Active, tRC ≥ tRC(min) IOL = 0 mA 50 Precharge Standby Current in Power Down Mode ICC2P CKE ≤ VIL(max), tCK = 10ns 80 ICC2PS CKE & CLK ≤ VIL(max), tCK = ∞ 80 ICC2N CKE ≥ VIH(min), /CS ≥ VIH(min), tCK = 10ns Input signals are changed one time during 2 clks. 9 ICC2NS CKE ≥ VIH(min), CLK ≤ VIL(max), tCK = ∞ Input signals are stable. 5 Precharge Standby Current in Non Power Down Mode Active Standby Current in Power Down Mode Active Standby Current in Non Power Down Mode CKE ≤ VIL(max), tCK = 10ns 1.0 ICC3PS CKE & CLK ≤ VIL(max), tCK = ∞ 0.5 ICC3N CKE ≥ VIH(min), /CS ≥ VIH(min), tCK = 10ns Input signals are changed one time during 2 clks. 18 ICC3NS CKE ≥ VIH(min), CLK ≤ VIL(max), tCK = ∞ Input signals are stable. 10 ICC4 tCK>tCK(min), IOL = 0 mA, Page Burst All Banks Activated, tCCD = 1 clk Auto Refresh Current (4K Cycle) ICC5 tRC ≥ tRFC(min), All Banks Active PASR Self Refresh Current 2 Banks 1 Bank Note mA 1 uA mA ICC3P Burst Mode Operating Current Unit mA mA 60 55 40 mA 1 mA 2 TCSR 45~85°C -25~45°C 200 ICC6 CKE ≤ 0.2V 170 45~85°C 180 -25~45°C 150 Deep Power Down Mode Current ICC7 10 uA uA Note : 1. Measured with outputs open. 2. Refresh period is 64ms. Rev. A | Mar. 2011 www.issi.com - [email protected] 27 IS42SM/RM/VM16200C Table12: AC Characteristic (AC operation conditions unless otherwise noted) Parameter CLK Cycle Time Access time from CLK (pos. edge) Sym -60 Min -75 Max Min CL = 3 tCK3 6.0 CL = 2 tCK2 10 CL = 3 tAC3 5.5 6 CL = 2 tAC2 8 8 1000 7.5 Max 10 Unit 1000 Note 1 2 CLK High-Level Width tCH 2.5 2.5 3 CLK Low-Level Width tCL 2.5 2.5 3 2.0 CKE Setup Time tCKS 1.5 CKE Hold Time tCKH 1.0 1.0 /CS, /RAS, /CAS, /WE, DQM Setup Time tCMS 1.5 2.0 /CS, /RAS, /CAS, /WE, DQM Hold Time tCMH 1.0 1.0 Address Setup Time tAS 1.5 2.0 Address Hold Time tAH 1.0 1.0 Data-In Setup Time tDS 1.5 2.0 Data-In Hold Time tDH 1.0 1.0 Data-Out High-Impedance Time from CLK (pos.edge) ns CL = 3 tHZ3 5.5 6 CL = 2 tHZ2 8 8 Data-Out Low-Impedance Time tLZ 1.0 1.0 Data-Out Hold Time (load) tOH 2.5 2.5 Data-Out Hold Time (no load) tOHN 1.8 ACTIVE to PRECHARGE command tRAS 42 PRECHARGE command period tRP 18 22.5 ACTIVE bank a to ACTIVE bank a command tRC 60 67.5 ACTIVE bank a to ACTIVE bank b command tRRD 12 15 4 1.8 100K 45 100K 5 ACTIVE to READ or WRITE delay tRCD 18 22.5 READ/WRITE command to READ/WRITE command tCCD 1 1 WRITE command to input data delay tDWD 0 0 Data-in to PRECHARGE command tDPL 12 15 Data-in to ACTIVE command tDAL 30 37.5 DQM to data high-impedance during READs tDQZ 2 2 6 DQM to data mask during WRITEs tDQM 0 0 6 LOAD MODE REGISTER command to ACTIVE or REFRESH command tMRD 2 2 8 CL = 3 tROH3 3 3 CL = 2 tROH2 2 2 Last data-in to burst STOP command tBDL 1 1 6 Last data-in to new READ/WRITE command tCDL 1 1 6 tCKED 1 1 Data-out to high-impedance from PRECHARGE command CKE to clock disable or power-down entry mode tPED Refresh period (4,096 refresh cycles) tREF AUTO REFRESH period tRFC 80 80 Exit SELF REFRESH to ACTIVE command tXSR 80 80 tT 0.5 Rev. A | Mar. 2011 6 6 ns CLK 7 7 6 9 CLK CKE to clock enable or power-down exit setup mode Transition time CLK 1 1 64 1.2 9 64 0.5 www.issi.com - [email protected] ms 5 ns 5 1.2 28 IS42SM/RM/VM16200C Note : 1. The clock frequency must remain constant (stable clock is defined as a signal cycling within timing constraints specified for the clock pin) during access or precharge states (READ, WRITE, including tDPL, and PRECHARGE commands). CKE may be used to reduce the data rate. 2. tAC at CL = 3 with no load is 5.5ns and is guaranteed by design. Access time to be measured with input signals of 1V/ns edge rate, from 0.8V to 0.2V. If tR > 1ns, then (tR/2-0.5)ns should be added to the parameter. 3. AC characteristics assume tT = 1ns. If tR & tF > 1ns, then [(tR+tF)/2-1]ns should be added to the parameter. 4. tHZ defines the time at which the output achieves the open circuit condition; it is not a reference to VOH or VOL. The last valid data element will meet tOH before going High-Z. 5. Parameter guaranteed by design. 6. Required clocks are specified by JEDEC functionality and are not dependent on any timing parameter. 7. Timing actually specified by tDPL plus tRP; clock(s) specified as a reference only at minimum cycle rate 8. JEDEC and PC100 specify three clocks. 9. Timing actually specified by tCKs; clock(s) specified as a reference only at minimum cycle rate. 10. A new command can be given tRC after self refresh exit. Rev. A | Mar. 2011 www.issi.com - [email protected] 29 IS42SM/RM/VM16200C Special Operation for Low Power Consumption Temperature Compensated Self Refresh Temperature Compensated Self Refresh allows the controller to program the Refresh interval during SELF REFRESH mode, according to the case temperature of the Low Power SDRAM device. This allows great power savings during SELF REFRESH during most operating temperature ranges. Only during extreme temperatures would the controller have to select a TCSR level that will guarantee data during SELF REFRESH. Every cell in the DRAM requires refreshing due to the capacitor losing its charge over time. The refresh rate is dependent on temperature. At higher temperatures a capacitor loses charge quicker than at lower temperatures, requiring the cells to be refreshed more often. Historically, during Self Refresh, the refresh rate has been set to accommodate the worst case, or highest temperature range expected. Thus, during ambient temperatures, the power consumed during refresh was unnecessarily high, because the refresh rate was set to accommodate the higher temperatures. Setting M4 and M3, allow the DRAM to accommodate more specific temperature regions during SELF REFRESH. There are four temperature settings, which will vary the SELF REFRESH current according to the selected temperature. This selectable refresh rate will save power when the DRAM is operating at normal temperatures. Partial Array Self Refresh For further power savings during SELF REFRESH, the PASR feature allows the controller to select the amount of memory that will be refreshed during SELF REFRESH. The refresh options are Two Bank;all two banks, One Bank;bank a. WRITE and READ commands can still occur during standard operation, but only the selected banks will be refreshed during SELF REFRESH. Data in banks that are disabled will be lost. Deep Power Down Deep Power Down is an operating mode to achieve maximum power reduction by eliminating the power of the whole memory array of the devices. Data will not be retained once the device enters Deep Power Down Mode. This mode is entered by having all banks idle then /CS and /WE held low with /RAS and /CAS held high at the rising edge of the clock, while CKE is low. This mode is exited by asserting CKE high. Rev. A | Mar. 2011 www.issi.com - [email protected] 30 IS42SM/RM/VM16200C Figure7: Deep Power Down Mode Entry CLK CKE /CS /RAS /CAS /WE tRP Deep Power Down Entry Precharge if needed DON’T CARE Figure8: Deep Power Down Mode Exit CLK CKE /CS /RAS /CAS /WE 100 µ s Deep Power Down Exit tRP tRFC Auto Refresh All Banks Precharge Mode Register Set Auto Refresh New Command Extended Mode Register Set DON’T CARE Rev. A | Mar. 2011 www.issi.com - [email protected] 31 IS42SM/RM/VM16200C Rev. A | Mar. 2011 www.issi.com - [email protected] 32 IS42SM/RM/VM16200C Ordering Information – VDD = 1.8V Industrial Range: (-40oC to +85oC) Configuration Frequency (MHz) Speed (ns) Order Part No. Package 2Mx16 166 6 IS42VM16200C-6BLI 54-ball BGA, Lead-free 133 7.5 IS42VM16200C-75BLI 54-ball BGA, Lead-free Order Part No. Package Ordering Information – VDD = 2.5V Industrial Range: (-40oC to +85oC) Configuration Frequency (MHz) Speed (ns) 2Mx16 166 6 IS42RM16200C-6BLI 54-ball BGA, Lead-free 133 7.5 IS42RM16200C-75BLI 54-ball BGA, Lead-free Order Part No. Package Ordering Information – VDD = 3.3V Industrial Range: (-40oC to +85oC) Configuration Frequency (MHz) Speed (ns) 2Mx16 166 6 IS42SM16200C-6BLI 54-ball BGA, Lead-free 133 7.5 IS42SM16200C-75BLI 54-ball BGA, Lead-free Rev. A | Mar. 2011 www.issi.com - [email protected] 33