DS1610 Partitioned NV Controller www.dalsemi.com FEATURES PIN ASSIGNMENT Converts CMOS RAMs into nonvolatile memories SOIC version is pin-compatible with the Dallas Semiconductor DS1210 NV Controller Unconditionally write protects all of memory when VCC is out of tolerance Write protects selected blocks of memory regardless of VCC status when programmed Automatically switches to battery backup supply when power-fail occurs Provides for multiple batteries Consumes less than 100 nA of battery current Test battery on power-up by inhibiting the second memory cycle Optional 5% or 10% power-fail detection 16-pin DIP or 16-pin SOIC surface-mount package Low forward voltage drop on the VCC switch with currents of up to 150 mA Optional industrial temperature range of -40°C to +85°C AW 1 16 PFO VCCO 2 15 VCCI AX 3 14 AZ VBAT1 AY 4 13 VBAT2 5 12 WEO TOL 6 11 CEO DIS 7 10 WEI GND 8 9 CEI 16-Pin DIP and 16-Pin SOIC PIN DESCRIPTION VCCI VBAT1 VBAT2 VCCO GND CEI CEO WEI WEO TOL AW - AZ DIS PFO - Input +5 Volt Supply - + Battery 1 Input - + Battery 2 Input - RAM Power (VCC) Supply - Ground - Chip Enable Input - Chip Enable Output - Write Enable Input - Write Enable Output - Power Supply Tolerance Select - Address Inputs - Memory Partition Disable - Power-Fail Output DESCRIPTION The DS1610 is a low-power CMOS circuit which solves the application problems of converting CMOS RAMS into nonvolatile memories. In addition the device has the ability to unconditionally write protect blocks of memory so that inadvertent write cycles do not corrupt program and special data space. The power supply incoming voltage at the VCCI input pin is constantly monitored for an out-of-tolerance condition. When such a condition is detected, both the chip enable and write enable outputs are inhibited to protect stored data. The battery inputs are used to supply VCCO with power when VCCI is less than the battery input voltages. Special circuitry uses a low leakage CMOS process which affords precise voltage detection at extremely low current consumption. By combining the DS1610 Partitioned NV Controller chip with a CMOS memory and batteries, nonvolatile RAM operation can be achieved. The DS1610 Partitioned NV Controller functions like the Dallas Semiconductor DS1210 NV controller when the ( DIS ) disable pin is grounded. An internal pulldown resistor to ground on the DIS pin of the DS1610S allows it to retrofit into DS1210S applications. When the DIS pin is grounded the address inputs AW - AZ and the write enable input WEI are ignored. Also the power-fail output PFO and the write enable output WEO are tristated. 1 of 10 111999 DS1610 OPERATION - DISABLE PIN CONNECTED TO VCCO The DS1610 performs five circuit functions required to battery backup a RAM. First, a switch is provided to direct power from the battery or the incoming power supply (VCCI) depending on which is greater. This switch has a voltage drop of less than 0.2 volts. The second function provided by the DS1610 is powerfail detection. The incoming supply (VCCI) is constantly monitored. When the supply goes out of tolerance a precision comparator detects power failure and inhibits both the chip enable output ( CEO ) and the write enable output ( WEO ). A third function of write protection is accomplished by holding both the chip enable output CEO and write enable output WEO to within 0.2 volts of VCCO when VCCI is out of tolerance. If CEI is low at the time that power-fail detection occurs the CEO signal is kept low until CEI is brought high again. However, CEO is forced high after 1.5 µs regardless of the state of CEI . Similarly, if WEI is low at the time that power fail detection occurs, the WEO signal will remain low until WEI is brought high or 1.5 µs elapses. The delay of write protection until the current memory cycle is complete prevents corrupted data. Power-fail detection occurs in the range of 4.75 to 4.5 volts with the tolerance pin TOL grounded. If the tolerance pin is connected to VCCO then power-fail detection occurs in the range of 4.5 volts to 4.25 volts. The PF0 signal is driven low and remains low until VCCI returns to nominal conditions. During nominal supply conditions CEO will follow CEI and WEO will follow WEI . The fourth function which the DS1610 performs is a battery status warning so that potential data loss is avoided. Each time VCCI is applied to the device battery status is checked with a precision comparator. If during battery backup no switch occurred from one battery to the other, the voltage of the battery supplying power when VCCI is applied is checked. If this voltage is less than 2.0 volts the second chip enable cycle after power is applied is inhibited. If any switch from one battery to another did occur the voltage of both batteries is checked. If either voltage is less than 2.0 volts the second chip enable cycle will be inhibited. Battery status can therefore be determined by performing a read cycle after power up to any location in memory, verifying that memory location’s contents. A subsequent write cycle can then be executed to the same memory location altering the data. If the next read cycle fails to verify the written data then the data is in danger of being corrupted. The fifth function of the DS1610 provides for battery redundancy. When data integrity is extremely important it is wise to use two batteries to insure reliability. The DS1610 controller provides an internal isolation switch which allows the connection of two batteries. When entering battery backup operation, the battery with the highest voltage is selected for use. If one battery should fail, the other would then supply energy to the connected load. The switch to a redundant battery is transparent to circuit operation and to the user. In applications where battery redundancy is not a major concern a single battery should be connected to the BAT1 pin. The BAT2 battery pin must be grounded. When batteries are first connected to one or both of the VBAT pins VCCO will not show the battery potential until VCCI is applied and removed for the first time. OPERATION - WRITE PROTECTION PROGRAMMING MODE When the disable pin is connected to VCCI or VCCO, the DS1610 performs all of the functions described earlier with the addition of a partition switch which selectively write protects blocks of memory. The state of the DIS pin is strobed and latched as VCCI crosses the power-fail trip point so that the DS1610 maintains its configuration during power loss. If the strobed value of DIS is a high the internal pulldown resistor on the DIS pin will be disconnected in the power-fail state to eliminate the possibility of battery discharge. The register controlling the partition switch is selected by recognition of a specific binary pattern which is sent on address lines AW -AZ. These address lines are normally the four upper order address lines being sent to RAM. The pattern is sent by 20 consecutive read cycles with the exact pattern as shown in Table 1. Pattern matching must be accomplished using read cycles; any write cycles will reset the pattern matching circuitry. If this pattern is matched perfectly, then the 21st through 24th read cycle will load the partition switch. Since there are 16 possible write protected partitions, the size of each partition is determined by the size of the memory. For example, a 128k X 8 memory would be divided into 16 partitions of 128k/16 or 8k X 8. Each partition is represented by one of the 16 bits contained in the 2 of 10 DS1610 21st through 24th read cycle as defined by AW through AZ and shown in Table 2. A logical 1 in a bit location sets that partition to write protect. A logical 0 in a bit location disables write protection. For example, if during the pattern match sequence bit 22 on address pin AX were a 1, this would cause the partition register location for partition 5 to be set to a 1. This in turn would cause the DS1610 to inhibit WEO from going low as WEI goes low whenever AZAYAXAW=0101. Note that while setting the partition register, data which is being accessed from the RAM should be ignored as the purpose of the 24 read cycles is to set the partition switch and not for the purpose of accessing data from RAM. Also note that on initial battery attach the partition register can power-up in any state. PATTERN MATCH TO WRITE PARTITION REGISTER Table 1 AW AX AY AZ 1 1 1 1 1 2 0 1 1 1 3 1 1 1 0 4 1 1 1 0 5 1 1 0 0 6 1 0 0 1 7 0 0 1 1 8 0 1 1 1 9 1 1 1 0 10 1 1 0 0 11 1 0 0 1 12 0 0 1 0 13 0 1 0 0 14 0 0 1 0 15 0 1 0 1 16 0 1 1 0 17 1 0 0 1 18 1 0 0 0 19 0 0 0 0 20 1 0 1 0 21 X X X X 22 X X X X 23 X X X X 24 X X X X PARTITION REGISTER MAPPING Table 2 Address Pin AW AX AY AZ AW AX AY AZ AW AX AY AZ AW AX AY AZ Bit number in pattern Match sequence BIT 21 BIT 21 BIT 21 BIT 21 BIT 22 BIT 22 BIT 22 BIT 22 BIT 23 BIT 23 BIT 23 BIT 23 BIT 24 BIT 24 BIT 24 BIT 24 Partition Number PARTITION 0 PARTITION 1 PARTITION 2 PARTITION 3 PARTITION 4 PARTITION 5 PARTITION 6 PARTITION 7 PARTITION 8 PARTITION 9 PARTITION 10 PARTITION 11 PARTITION 12 PARTITION 13 PARTITION 14 PARTITION 15 3 of 10 Address State Affected (AZ AY AX AW) 0000 0001 0010 0011 0100 0101 0110 0111 1000 1001 1010 1011 1100 1101 1110 1111 DS1610 ABSOLUTE MAXIMUM RATINGS* Voltage on Any Pin Relative to Ground Operating Temperature Storage Temperature Soldering Temperature * -0.5V to +7.0V 0°C to 70°C -55°C to +125°C 260°C for 10 seconds This is a stress rating only and functional operation of the device at these or any other conditions above those indicated in the operation sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods of time may affect reliability. RECOMMENDED DC OPERATING CONDITIONS PARAMETER Pin 6 = GND Supply Voltage Pin 6 = VCCO Supply Voltage Logic 1 Input Logic 0 Input Battery Input SYMBOL VCCI VCCI VIH VIL VBAT1, VBAT2 MIN 4.75 4.5 2.0 -0.3 2.0 TYP 5.0 5.0 (0°C to 70°C) MAX 5.5 5.5 VCC+0.3 +0.8 4.0 UNITS V V V V V NOTES 1 1 1 1 1, 2 UNITS mA µA V mA µA µA V V ȍ ȍ mA mA NOTES 3, 14 3, 15 1 4 DC ELECTRICAL CHARACTERISTICS (0°C to 70°C, VCCI WITHIN DC OPERATING CONDITIONS) PARAMETER Operating Current Standby Current Supply Voltage Supply Current Input Leakage Output Leakage VCC Trip Point (TOL=GND) VCC Trip Point (TOL=VCC) CEI to CEO Impedance DIS Pulldown Resistance PFO , WEO Output @ 2.4V PFO , WEO Output @ 0.4V SYMBOL ICC1 ICC2 VCCO ICCO1 IIL ILO VCCTP VCCTP ZCE RDIS IOH IOL MIN TYP VCC-0.2 -1.0 -1.0 4.50 4.25 4.62 4.37 50k -1.0 SYMBOL VOHL VOHL IBAT ICCO2 150 +1.0 +1.0 4.75 4.50 30 250k 4.0 DC ELECTRICAL CHARACTERISTICS PARAMETER CEO Output WEO Output VBAT1or VBAT2 Battery Current Battery Backup Current @ VCCO = VBAT -0.2V MAX 5 200 MIN VBAT-0.2 VBAT-0.2 10, 16 10, 16 (0°C to 70°C; VCC<4.5V) TYP MAX 100 150 4 of 10 1, 16 1, 16 5 UNITS V V nA µA NOTES 2, 3 6, 7, 8 DS1610 CAPACITANCE PARAMETER Input Capacitance Output Capacitance (tA = 25°C) SYMBOL CIN COUT MIN TYP MAX 5 7 UNITS pF pF NOTES (0°C to 70°C; VCCI = 4.75V to 5.50V, TOL= GND) (VCCI = 4.50V to 5.50V, TOL-VCCO) AC ELECTRICAL CHARACTERISTICS PARAMETER Address Setup Address Hold Read Recovery CEI , WEI Pulse Width CEI to CEO Falling Propagation Delay Later of CEI , WEI to WEO Falling Propagation Delay CEI to CEO Rising Propagation Delay Earlier of CEI , WEI to WEO Rising Propagation Delay Write Recovery SYMBOL tAS tAH tRR tCW tPDF MIN 0 50 10 75 5 UNITS ns ns ns ns ns NOTES 9 9 9 9 10 tPDF 20 ns 10, 11 tPDR 5 ns 10 tPDR 5 ns 10, 11 ns 9, 11 tWR TYP 10 AC ELECTRICAL CHARACTERISTICS PARAMETER Recovery at Power-Up VCC Slew Rate Power-Down VCC Slew Rate Power-Down VCC Slew Rate Power-Up CEO Pulse Width WEO Pulse Width SYMBOL tREC tF tFB tF tWP, tCE tWP, tCE MAX (0°C to 70°C; VCC<4.5V) MIN 25 300 10 0 TYP MAX 125 1.5 1.5 5 of 10 UNITS ms µs µs µs µs µs NOTES 12 13 7, 8 7, 8 DS1610 TIMING DIAGRAM: POWER-UP TIMING DIAGRAM: POWER-DOWN 6 of 10 DS1610 TIMING DIAGRAM: LOADING PARTITION REGISTER OUTPUT LOAD Figure 1 7 of 10 DS1610 NOTES: 1. All voltages are reference to ground 2. Only one battery input is required. 3. Measured with outputs open circuited. 4. ICC01 is the maximum average load which the DS1610 can supply to the memories. 5. ZCE is an average input-to-output impedance as the input is swept from ground to VCCI and less than 4 mA is forced through ZCE. 6. ICC02 is the maximum average load current which the DS1610 can supply to the memories in the battery backup mode. 7. tCE max must be met to insure data integrity on power loss. 8. Chip Enable Output CEO can only sustain leakage current in the battery mode. 9. Applies only when loading partition switch. 10. Measured with a load as shown in Figure 1. 11. Measured with DIS at a logic high level. 12. CEO and WEO will be held high for a time equal to tREC (max = 125 ms) after VCCI crosses VCCTP. 13. tR is the slew rate of VCCI from 4.25V to 4.75V. 14. CEI , WEI , AW - AZ run at minimum timing set and at voltage levels of 0V to 3V. 15. All inputs within 0.3V of ground or VCCI and CEI within 0.3V of VCCI. 16. The power-fail output signal ( PFO ) is driven active (VOL = 0.4V) when the VCC trip point occurs. While active, the PFO pin can sink 4 mA and will maintain a maximum output voltage of 0.4 volts. When inactive, the voltage output of PFO is 2.4 volts minimum and will source a current of 1 mA. 8 of 10 DS1610 DS1610 16-PIN DIP (300-MIL) PKG DIM A IN. MM B IN. MM C IN. MM D IN. MM E IN. MM F IN. MM G IN. MM H IN. MM J IN. MM K IN. MM 16-PIN MIN MAX 0.740 0.780 18.80 19.81 0.240 0.260 6.10 6.60 0.120 0.140 3.05 3.56 0.300 0.325 7.62 8.26 0.015 0.040 0.38 1.02 0.120 0.140 3.04 3.56 0.090 0.110 2.29 2.79 0.320 0.370 8.13 9.40 0.008 0.012 0.20 0.30 0.015 0.021 0.38 0.53 9 of 10 DS1610 DS1610 16-PIN SOIC (300-MIL) PKG DIM A IN. MM B IN. MM C IN. MM E IN. MM F IN. MM G IN. MM H IN. MM J IN. MM K IN. MM L IN. MM PHI 16-PIN MIN MAX 0.402 0.412 10.21 10.46 0.290 0.300 7.37 7.65 0.089 0.095 2.26 2.41 0.004 0.012 0.102 0.30 0.094 0.105 2.38 2.68 .050 BSC 1.27 BSC 0.398 0.416 10.11 10.57 0.009 0.013 0.229 0.33 0.013 0.019 0.33 0.48 .016 .040 .40 1.02 0° 8° 10 of 10