19-6032; Rev 9/11 DS1672 I C 32-Bit Binary Counter RTC 2 GENERAL DESCRIPTION FEATURES The DS1672 incorporates a 32-bit counter and power-monitoring functions. The 32-bit counter is designed to count seconds and can be used to derive time-of-day, week, month, month, and year by using a software algorithm. A precision, temperature-compensated reference and comparator circuit monitors the status of VCC. When an out-of-tolerance condition occurs, an internal power-fail signal is generated that forces the reset to the active state. When VCC returns to an in-tolerance condition, the reset signal is kept in the active state for a period of time to allow the power supply and processor to stabilize. 32-Bit Counter I2C Serial Interface Automatic Power-Fail Detect and Switch Circuitry Power-Fail Reset Output Low-Voltage Oscillator Operation (1.3V min) Trickle-Charge Capability Underwriters Laboratories (UL) Recognized -40C to +85C Operating Range PIN CONFIGURATION TOP VIEW TYPICAL OPERATING CIRCUIT X1 1 DS1672 1 of 15 VCC X2 2 7 RST VBACKUP 3 6 SCL GND 4 5 SDA PDIP SO SOP . 8 DS1672 ORDERING INFORMATION PART TEMP RANGE VOLTAGE (V) PIN-PACKAGE TOP MARK* DS1672-2+ -40C to +85C 2.0 8 PDIP (300 mils) DS1672-2 DS1672-3+ -40C to +85C 3.0 8 PDIP (300 mils) DS1672-3 DS1672-33+ -40C to +85C 3.3 8 PDIP (300 mils) DS1672-33 DS1672S-2+ -40C to +85C 2.0 8 SO (150 mils) D1672-2 DS1672S-3+ -40C to +85C 3.0 8 SO (150 mils) D1672-3 DS1672S-33+ -40C to +85C 3.3 8 SO (150 mils) D167233 DS1672S-3+T&R -40C to +85C 3.0 DS1672S-33+T&R -40C to +85C 3.3 DS1672U-2+ -40C to +85C 2.0 DS1672U-3+ -40C to +85C 3.0 DS1672U-33+ -40C to +85C 3.3 DS1672U-33+T&R -40C to +85C 3.3 8 SO (150 mils)/Tape D1672-3 and Reel 8 SO (150 mils)/Tape D167233 and Reel 1672 8 SOP(3mm) rr -2 1672 8 SOP(3mm) rr -3 1672 8 SOP(3mm) rr -33 8 SOP(3mm)/Tape 1672 rr -33 and Reel + Denotes a lead-free/RoHS-compliant device. * A "+" anywhere on the top mark denotes a lead-free device. rr = 2-digit alphanumeric revision code. 2 of 15 DS1672 ABSOLUTE MAXIMUM RATINGS Voltage Range on Any Pin Relative to Ground.....................................................-0.5V to +6.0V Operating Temperature Range (noncondensing) ...................................................-40C to +85C Storage Temperature Range.........................................................................-55C to +125C Soldering Temperature (reflow)....................................................................... +260C Lead Temperature (soldering, 10s) .......................................................................... +260C This is a stress rating only and functional operation of the device at these or any other conditions beyond those indicated in the operation sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods of time can affect device reliability. RECOMMENDED OPERATING CONDITIONS (TA = -40C to +85C) (Note 1) PARAMETER DS1672-2 Supply DS1672-3 Voltage DS1672-33 Logic 1 Logic 0 Backup Supply Voltage SYMBOL VCC VCC VCC VIH VIL VBACKUP MIN 1.8 2.7 2.97 0.7 x VCC -0.5 1.3 TYP 2.0 3.0 3.3 3.0 MAX 5.5 5.5 5.5 VCC + 0.5 +0.3 x VCC 3.63 MIN TYP UNITS V V V V Note 1: All voltages referenced to ground. DC ELECTRICAL CHARACTERISTICS (VCCMIN < VCC < VCCMAX, TA = -40C to +85C.) (Note 1) PARAMETER Active Supply Current (Note 2) Standby Current (Note 3) Power-Fail Voltage VBACKUP Leakage Current Logic 0 Output (Note 4) Logic 0 Output (Note 4, DS1672-2 Only) SYMBOL CONDITIONS ICCA -2: VCC = 2.2V -3: VCC = 3.3V -33: VCC = 3.63V ICCS -2: VCC = 2.2V -3: VCC = 3.3V -33: VCC = 3.63V VPF -2: -3: -33: IBACKUPLKG IOL VOL = 0.4V IOL VCC > 2V; VOL = 0.4V VCC < 2V; VOL = VCC * 0.2 2.70 2.45 1.58 2.88 2.60 1.70 25 Note 1: All voltages referenced to ground. Note 2: ICCA specified with SCL clocking at max frequency (400kHz), trickle charger disabled. Note 3: ICCS specified with VCC = VCCTYP and SDA, SCL = VCCTYP, trickle charger disabled. Note 4: SDA and RST. 3 of 15 MAX 600 UNITS A 500 A 2.97 2.70 1.80 50 3 3 V nA mA mA DS1672 DC ELECTRICAL CHARACTERISTICS (VCC = 0V, TA = -40C to +85C.) (Note 5) PARAMETER VBACKUP Current (Oscillator On) VBACKUP Current (Oscillator Off) SYMBOL MIN IBACKUPOSC IBACKUP TYP MAX UNITS 0.425 1 200 A nA MAX UNITS kHz k pF Note 5: Using the recommended crystal on X1 and X2. CRYSTAL SPECIFICATIONS* PARAMETER Nominal Frequency Series Resistance Load Capacitance SYMBOL fO ESR CL MIN TYP 32.768 45 6 *The crystal, traces, and crystal input pins should be isolated from RF generating signals. Refer to Application Note 58: Crystal Considerations for Dallas Real-Time Clocks for additional specifications 4 of 15 DS1672 AC ELECTRICAL CHARACTERISTICS (VCC = 0V, TA = -40C to +85C.) PARAMETER SCL Clock Frequency Bus Free Time Between a STOP and START Condition Hold Time (Repeated) START Condition (Note 6) SYMBOL tBUF tHD:STA HIGH Period of SCL Clock tHIGH Setup Time for a Repeated START Condition tSU:STA Data Hold Time (Notes 7, 8) tHD:DAT Data Setup Time (Note 9) tSU:DAT Capacitive Load for Each Bus Line (Note 10) I/O Capacitance Fast mode 100 TYP MAX kHz 1.3 Standard mode 4.7 Fast mode 0.6 Standard mode 4.0 Fast mode 1.3 Standard mode 4.7 Fast mode 0.6 Standard mode 4.0 Fast mode 0.6 Standard mode 4.7 Fast mode 0 Standard mode 0 Fast mode 100 Standard mode 250 tSU:STO s s s s s 0.9 300 Standard mode 1000 Standard mode 300 0.6 Standard mode 4.0 ns s CB 400 CI/O ns 300 20 + 0.1CB Fast mode s ns 20 + 0.1CB Fast mode tF 100 Fast mode Fast mode tR UNITS 400 Standard mode tLOW Setup Time for STOP Condition MIN fSCL LOW Period of SCL Clock Rise Time of Both SDA and SCL Signals (Note 10) Fall Time of Both SDA and SCL Signals (Note 10) CONDITIONS 10 pF pF Note 6: After this period, the first clock pulse is generated. Note 7: A device must internally provide a hold time of at least 300ns for the SDA signal (referenced to the VIHMIN of the SCL signal) in order to bridge the undefined region of the falling edge of SCL. Note 8:The maximum tHD:DAT has only to be met if the device does not stretch the LOW period (tLOW) of the SCL signal. Note 9: A fast-mode device can be used in a standard-mode system, but the requirement tSU:DAT to 250ns must then be met. This will automatically be the case if the device does not stretch the LOW period of the SCL signal. If such a device does stretch the LOW period of the SCL signal, it must output the next data bit to the SDA line tR max + tSU:DAT = 1000 + 250 = 1250ns before the SCL line is released. Note 10: CB-Total capacitance of one bus line in pF. 5 of 15 DS1672 POWER-UP/POWER-DOWN CHARACTERISTICS (TA = -40C to +85C) PARAMETER SYMBOL MIN TYP MAX UNITS 10 s VCC Detect to RST (VCC Falling) VCC Detect to RST (VCC Rising) (Note 11) VCC Fall Time; VPF(MAX) to VPF(MIN) tRPU tF 300 s VCC Rise Time; VPF(MIN) to VPF(MAX) tR 0 s tRPD 250 ms Note 11: If the EOSC bit in the control register is set to logic 1, tRPU is equal to 250ms plus the startup time of the crystal oscillator. Warning: Negative undershoots below -0.3V while the part is in battery-backed mode can cause loss of data. Figure 1. Timing Diagram SDA tBUF tLOW tF tHD:STA SCL tHD:STA tSU:STA tHD:DAT STOP tHIGH tSU:DAT tSU:STO REPEATED START START Figure 2. Power-Up/Power-Down Timing VCC VPF(max) VPF(min) tF tR tPD tRPU tRPD RST INPUTS DON'T CARE RECOGNIZED RECOGNIZED HIGH IMPEDANCE OUTPUTS VALID VALID 6 of 15 DS1672 PIN DESCRIPTION PIN NAME 1, 2 X1, X2 3 VBACKUP 4 GND 5 SDA 6 SCL 7 RST 8 VCC FUNCTION Connections for Standard 32.768kHz Quartz Crystal. The internal oscillator circuitry is designed for operation with a crystal having a specified load capacitance (CL) of 6pF. For more information about crystal selection and crystal layout considerations, refer to Application Note 58: Crystal Considerations with Dallas Real-Time Clocks. The DS1672 can also be driven by an external 32.768kHz oscillator. In this configuration, the X1 pin is connected to the external oscillator signal and the X2 pin is left unconnected. Battery Input for Any Standard 3V Lithium Cell or Other Energy Source. Battery voltage must be held between 1.3V and 3.63V for proper operation. Diodes placed in series between the power source and the VBACKUP pin may result in improper operation. If a backup supply is not required, VBACKUP must be grounded. UL recognized to ensure against reverse charging current when used in conjunction with a lithium battery (charger disabled). See "Conditions of Acceptability" at www.maxim-ic.com/qa/info/ul. Ground. Serial-Data Input/Output. SDA is the input/output pin for the I2C serial interface. The SDA pin is open drain and requires an external pullup resistor. I2C Serial-Clock Input. SCL is used to synchronize data movement on the serial interface and requires an external pullup resistor. Active-Low Reset Output. It functions as a microprocessor reset signal. This pin is an open-drain output and requires an external pullup resistor. Power pin for Primary Power Supply. When VCC is applied within normal limits, the device is fully accessible and data can be written and read. When VCC is below VPF, reads and writes are inhibited. Figure 3. Recommended Layout for Crystal LOCAL GROUND PLANE (LAYER 2) X1 CRYSTAL X2 GND 7 of 15 DS1672 Detailed Description The DS1672 provides a 32-bit counter that increments once-per-second. The counter data is accessible via an I2C serial interface. A precision, temperature-compensated, voltage reference and comparator circuit monitors VCC. When VCC drops below VPF, RST becomes active and the interface is disabled to prevent data corruption. The device switches to the backup supply input, which maintains oscillator and counter operation while VCC is absent. When VCC rises above VPF, RST remains low for a period of time (tRPU) to allow VCC to stabilize. The block diagram in Figure 4 shows the main elements of the DS1672. As shown, communications to and from the DS1672 occur serially over a I2C, bidirectional bus. The DS1672 operates as a slave device on the I2C bus. Access is obtained by implementing a START condition and providing a device identification code followed by a register address. Subsequent registers can be accessed sequentially until a STOP condition is executed. Figure 4. Block Diagram X1 X2 1Hz Oscillator and divider CL CL 32-Bit Counter (4 Bytes) Control Trickle Charger VCC VBACKUP Power Control GND RST Control Logic Dallas Semiconductor DS1672 N SCL I2C Interface Address Register SDA Oscillator Circuit The DS1672 uses an external 32.768kHz crystal. The oscillator circuit does not require any external resistors or capacitors to operate. Table 1 specifies several crystal parameters for the external crystal. Figure 4 shows a functional schematic of the oscillator circuit. If using a crystal with the specified characteristics, the startup time is usually less than one second. Table 1. Crystal Specifications* PARAMETER SYMBOL MIN TYP MAX UNITS NOTES Nominal Frequency FO 32.768 kHz Series Resistance ESR 45 k Load Capacitance CL 6 pF * The crystal, traces, and crystal input pins should be isolated from RF generating signals. Refer to Application Note 58: Clock Accuracy The accuracy of the clock is dependent upon the accuracy of the crystal and the accuracy of the match between the capacitive load of the oscillator circuit and the capacitive load for which the crystal was 8 of 15 DS1672 trimmed. Additional error will be added by crystal frequency drift caused by temperature shifts. External circuit noise coupled into the oscillator circuit may result in the clock running fast. Refer to Application Note 5: "Crystal Considerations with Dallas Real-Time Clocks" for detailed information. Address Map The counter is accessed by reading or writing the first 4 bytes of the DS1672 (00h-03h). The control register and trickle charger are accessed by reading or writing the appropriate register bytes as illustrated in Table 2. If the master continues to send or request more data after the address pointer has reached 05h, the address pointer will wrap around to location 00h. Table 2. Registers ADDRESS 00h 01h 02h 03h 04h 05h B7 B6 B5 B4 B3 B2 B1 B0 LSB MSB EOSC TCS TCS TCS TCS DS DS RS RS FUNCTION Counter Byte 1 Counter Byte 2 Counter Byte 3 Counter Byte 4 Control Trickle Charger Power Control The device is fully accessible and data can be written and ready only when VCC is greater than VPF. However, when VCC falls below VPF, (point at which write protection occurs) the internal clock registers are blocked from any access. If VPF is less than VBACKUP, the device power is switched from VCC to VBACKUP when VCC drops below VPF. If VPF is greater than VBACKUP, the device power is switched from VCC to VBACKUP when VCC drops below VBACKUP. Oscillator and counter operation are maintained from the VBACKUP source until VCC is returned to nominal levels (see Table 3). Table 3. Power Control SUPPLY CONDITION VCC < VPF, VCC < VBACKUP VCC < VPF, VCC > VBACKUP VCC > VPF, VCC < VBACKUP VCC > VPF, VCC > VBACKUP READ/WRITE ACCESS No No Yes Yes RST POWERED BY Active Active Inactive Inactive VBACKUP VCC VCC VCC Oscillator Control The EOSC bit (bit 7 of the control register) controls the oscillator when in back-up mode. This bit when set to logic 0 will start the oscillator. When this bit is set to a logic 1, the oscillator is stopped and the DS1672 is placed into a low-power standby mode (IBACKUP) when in back-up mode. When the DS1672 is powered by VCC, the oscillator is always on regardless of the status of the EOSC bit; however, the counter is incremented only when EOSC is a logic 0. Microprocessor Monitor A temperature-compensated comparator circuit monitors the level of VCC. When VCC falls to the powerfail trip point, the RST signal (open drain) is pulled active, and read/write access is inhibited. When VCC returns to nominal levels, the RST signal is kept in the active state for tRPU (typically) to allow the power supply and microprocessor to stabilize. Note, however, that if the EOSC bit is set to a logic 1 (to disable the oscillator during write protection), the reset signal will be kept in an active state for tRPU plus the startup time of the oscillator. 9 of 15 DS1672 Trickle Charger The trickle charger is controlled by the trickle charge register. The simplified schematic of Figure 5 shows the basic components of the trickle charger. The trickle charge select (TCS) bit (bits 4-7) controls the selection of the trickle charger. In order to prevent accidental enabling, only a pattern on 1010 will enable the trickle charger. All other patterns will disable the trickle charger. The DS1672 powers up with the trickle charger disabled. The diode select (DS) bits (bits 2, 3) select whether or not a diode is connected between VCC and VBACKUP. If DS is 01, no diode is selected or if DS is 10, a diode is selected. The RS bits (bits 0, 1) select whether a resistor is connected between VCC and VBACKUP and what the value of the resistor is. The resistor selected by the resistor select (RS) bits and the diode selected by the diode select (DS) bits are as follows: TCS TCS TCS TCS DS DS RS RS X X X 1 1 1 1 1 1 0 X X X 0 0 0 0 0 0 0 X X X 1 1 1 1 1 1 0 X X X 0 0 0 0 0 0 0 0 1 X 0 1 0 1 0 1 0 0 1 X 1 0 1 0 1 0 0 X X 0 0 0 1 1 1 1 0 X X 0 1 1 0 0 1 1 0 FUNCTION Disabled Disabled Disabled No diode, 250 resistor One diode, 250 resistor No diode, 2k resistor One diode, 2k resistor No diode, 4k resistor One diode, 4k resistor Initial default value--disabled Warning: The resistor value of 250 must not be selected whenever VCC is greater than 3.63V. Diode and resistor selection is determined by the user according to the maximum current desired for battery or super cap charging. The maximum charging current can be calculated as illustrated in the following example. Assume that a system power supply of 3V is applied to VCC and a super cap is connected to VBACKUP. Also assume that the trickle charger has been enabled with a diode and resistor R2 between VCC and VBACKUP. The maximum current IMAX would, therefore, be calculated as follows: IMAX = (5.0V - diode drop) / R1 (5.0V - 0.6V) / 2k 2.2mA As the super cap changes, the voltage drop between VCC and VBACKUP will decrease and, therefore, the charge current will decrease. 10 of 15 DS1672 Figure 5. Programmable Trickle Charger R1 VCC 250 VBACKUP R2 2k R3 4k 1 OF 16 SELECT 1 OF 2 SELECT NOTE: ONLY 1010 ENABLES TCS BIT 7 TCS BIT 6 TCS BIT 5 TCS BIT 4 DS BIT 3 DS BIT 2 1 OF 3 SELECT RS BIT 1 RS BIT 0 TCS = TRICKLE CHARGER SELECT DS = DIODE SELECT RS = RESISTOR SELECT TRICKLE CHARGE REGISTER I2C Serial Data Bus The DS1672 supports a bidirectional I2C bus and data transmission protocol. A device that sends data onto the bus is defined as a transmitter and a device receiving data as a receiver. The device that controls the message is called a master. The devices that are controlled by the master are slaves. The bus must be controlled by a master device that generates the serial clock (SCL), controls the bus access, and generates the START and STOP conditions. The DS1672 operates as a slave on the I2C bus. Connections to the bus are made via the open-drain I/O lines SDA and SCL. Within the bus specifications, a standard mode (100kHz maximum clock rate) and a fast mode (400kHz maximum clock rate) are defined. The DS1672 operates in both modes. The following bus protocol has been defined (Figure 6): Data transfer may be initiated only when the bus is not busy. During data transfer, the data line must remain stable whenever the clock line is HIGH. Changes in the data line while the clock line is high will be interpreted as control signals. Accordingly, the following bus conditions have been defined: Bus not busy: Both data and clock lines remain HIGH. Start data transfer: A change in the state of the data line from high to low, while the clock line is high, defines a START condition. Stop data transfer: A change in the state of the data line from low to high, while the clock line is high, defines a STOP condition. 11 of 15 DS1672 Data valid: The state of the data line represents valid data when, after a START condition, the data line is stable for the duration of the high period of the clock signal. The data on the line must be changed during the low period of the clock signal. There is one clock pulse per bit of data. Each data transfer is initiated with a START condition and terminated with a STOP condition. The number of data bytes transferred between the START and the STOP conditions is not limited, and is determined by the master device. The information is transferred byte-wise and each receiver acknowledges with a ninth bit. Within the I2C bus specifications a standard mode (100kHz clock rate) and a fast mode (400kHz clock rate) are defined. Acknowledge: Each receiving device, when addressed, is obliged to generate an acknowledge after the reception of each byte. The master device must generate an extra clock pulse that is associated with this acknowledge bit. A device that acknowledges must pull down the SDA line during the acknowledge clock pulse in such a way that the SDA line is stable LOW during the HIGH period of the acknowledge related clock pulse. Of course, setup and hold times must be taken into account. A master must signal an end of data to the slave by not generating an acknowledge bit on the last byte that has been clocked out of the slave. In this case, the slave must leave the data line HIGH to enable the master to generate the STOP condition. Figures 7 and 8 detail how data transfer is accomplished on the I2C bus. Depending upon the state of the R/W bit, two types of data transfer are possible: 1) Data transfer from a master transmitter to a slave receiver. The first byte transmitted by the master is the slave address. Next follows a number of data bytes. The slave returns an acknowledge bit after each received byte. 2) Data transfer from a slave transmitter to a master receiver. The first byte (the slave address) is transmitted by the master. The slave then returns an acknowledge bit. Next follows a number of data bytes transmitted by the slave to the master. The master returns an acknowledge bit after all received bytes other than the last byte. At the end of the last received byte, a "not acknowledge" is returned. The master device generates all of the serial clock pulses and the START and STOP conditions. A transfer is ended with a STOP condition or with a repeated START condition. Since a repeated START condition is also the beginning of the next serial transfer, the bus will not be released. The DS1672 can operate in the following two modes: 1) Slave receiver mode (DS1672 write mode): Serial data and clock are received through SDA and SCL. After each byte is received, an acknowledge bit is transmitted. START and STOP conditions are recognized as the beginning and end of a serial transfer. Address recognition is performed by hardware after reception of the slave address and direction bit (Figure 7). The slave address byte is the first byte received after the START condition is generated by the master. The slave address byte contains the 7-bit DS1672 address, which is 1101000, followed by the direction bit (R/W), which for a write is a 0. After receiving and decoding the slave address byte the DS1672 outputs an acknowledge on the SDA line. After the DS1672 acknowledges the slave address + write bit, the master transmits a word address to the DS1672. This will set the register pointer on the DS1672, with the DS1672 acknowledging the transfer. The master may then transmit zero or more bytes of data, 12 of 15 DS1672 with the DS1672 acknowledging each byte received. The register pointer will increment after each byte is transferred. The master will generate a stop condition to terminate the data write. 2) Slave transmitter mode (DS1672 read mode): The first byte is received and handled as in the slave receiver mode. However, in this mode, the direction bit will indicate that the transfer direction is reversed. Serial data is transmitted on SDA by the DS1672 while the serial clock is input on SCL. START and STOP conditions are recognized as the beginning and end of a serial transfer (Figure 8). The slave address byte is the first byte received after the START condition is generated by the master. The slave address byte contains the 7-bit DS1672 address, which is 1101000, followed by the direction bit (R/W), which for a read is a 1. After receiving and decoding the slave address byte the DS1672 outputs an acknowledge on the SDA line. The DS1672 then begins to transmit data starting with the register address pointed to by the register pointer. If the register pointer is not written to before the initiation of a read mode the first address that is read is the last one stored in the register pointer. The DS1672 must receive a "not acknowledge" to end a read. Figure 6. Data Transfer on I2C Serial Bus SDA MSB slave address R/W direction bit acknowledgement signal from receiver acknowledgement signal from receiver SCL 1 2 6 7 8 9 1 2 3-8 ACK repeated if more bytes are transferred S 1101000 <RW> Figure 7. Data Write: Slave Receiver Mode 0 <Word Address (n)> A XXXXXXXX S - START A - ACKNOWLEDGE P - STOP <Data(n) A XXXXXXXX <Data(n+1)> A XXXXXXXX <Data(n+X)> A XXXXXXXX DATA TRANSFERRED (X+1 BYTES + ACKNOWLEDGE) R/W - READ/WRITE OR DIRECTION BIT ADDRESS = D0H 13 of 15 9 ACK START CONDITION <Slave Address> 8 A P STOP CONDITION OR REPEATED START CONDITION DS1672 <Slave Address> S 1101000 <RW> Figure 8. Data Read: Slave Transmitter Mode 1 <Data(n)> A XXXXXXXX <Data(n+1) A XXXXXXXX <Data(n+2)> A XXXXXXXX <Data(n+X)> A XXXXXXXX A P S - START DATA TRANSFERRED A - ACKNOWLEDGE (X+1 BYTES + ACKNOWLEDGE); NOTE: LAST DATA BYTE IS P - STOP FOLLOWED BY A NOT ACKNOWLEDGE (A) SIGNAL) A - NOT ACKNOWLEDGE R/W - READ/WRITE OR DIRECTION BIT ADDRESS = D1H THERMAL INFORMATION PACKAGE 8 PDIP (300 mils) 8 SO (150 mils) 8 SOP (3mm) THETA-JA 110C/W 128.4C/W 206.3C/W THETA-JC 40C/W 36C/W 42C/W PACKAGE INFORMATION For the latest package outline information and land patterns (footprints), go to www.maxim-ic.com/packages. Note that a "+", "#", or "-" in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. PACKAGE TYPE 8 PDIP (300 mils) 8 SO (150 mils) 8 SOP (3mm) PACKAGE CODE P8+1 S8+5 U8+1 OUTLINE NO. 21-0043 21-0041 21-0036 14 of 15 LAND PATTERN NO. -- 90-0096 90-0092 DS1672 REVISION HISTORY REVISION DATE DESCRIPTION PAGES CHANGED 9/11 Updated the Ordering Information, Absolute Maximum Ratings, Recommended Operating Conditions, DC Electrical Characteristics, AC Electrical Characteristics, Pin Description, Trickle Charger, Thermal Information, and Package Information 2, 3, 5, 7, 10, 15 15 of 15 Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. M a x i m I n t e g r a t e d P r o d u c t s , 1 2 0 S a n G a b r i e l D r iv e , S u n n y v a le , C A 9 4 0 8 6 4 0 8- 7 3 7 - 7 6 0 0 (c) 2011 Maxim Integrated Products Maxim is a registered trademark of Maxim Integrated Products, Inc.