DS1336 Afterburner Chip www.dalsemi.com FEATURES PIN ASSIGNMENT Provides power switching of up to 1.5 amps at voltages between 3.0 and 5.0 volts Five separate power switches Selectable battery switches for use with battery-backed systems Very low on impedance of 0.7O Battery backup current of 4 mA Diode-isolated battery path Available in 16-pin DIP or 16-pin SOIC surface mount package Low voltage drop battery path Connects directly to a variety of Dallas Semiconductor devices, adding increased switching capability for large battery backup current applications 1 2 3 4 5 6 7 8 OUT5 PF IN5 IN2 IN4 VBATIN VBAT02 OUT4 16 15 14 13 12 11 10 9 VCC/IN1 PF GND OUT1 OUT2 OUT3 VBAT01 IN3 16-Pin DIP (300-mil) See Mach. Drawings Section OUT5 PF IN5 IN2 IN4 VBATIN VBAT02 OUT4 1 2 3 4 5 6 7 8 16 15 14 13 12 11 10 9 VCC/IN1 PF GND OUT1 OUT2 OUT3 VBAT01 IN3 16-Pin DIP SOIC (300-mil) See Mach. Drawings Section PIN DESCRIPTION VCC/IN1 IN2 - IN5 OUT1 - 5 VBATIN VBAT01 VBAT02 PF, PF GND - +5V Input and Input 1 - Inputs 2 - 5 - Outputs 1 - 5 - External Battery Input - Diode Protected Battery Output - Low Voltage Drop Battery Output - Power-fail Inputs - Ground DESCRIPTION The DS1336 Afterburner Chip is designed to provide power switching between a primary power supply (VCC) and a backup battery power supply (VBAT). Five VCC and two battery paths are provided which can be used individually or in parallel to supply uninterrupted power in applications such as SRAM networks. When used with one of the Dallas power monitoring devices listed in Table 1, the DS1336 allows a load to be switched from its main power supply VCC to a battery backup supply when VCC falls out of tolerance. A user may selectively tie together any combination of the output pins to provide the desired high current supply, providing up to 300 mA per OUT pin or a maximum of 1.5A. Depending upon the user's backup supply load requirements, either of the VBAT outputs may be tied to the OUT pins to supply 1 of 6 050699 DS1336 current when VCC is out of tolerance. The DS1336 switches back to the higher current VCC from battery current when PF and PF become inactive. OPERATION The required PF or PF input which controls the switching between the main VCC and backup battery can be supplied by any of the devices listed in Table 1. All of the devices provide the DS1336 with a PF or PF signal, switching between a main supply VCC and backup supply VBAT when VCC falls out of tolerance. For applications requiring switching from the VCC supply inputs to VBAT, the required PF or PF input to the DS1336 can be provided by the DS1236, DS1239, DS5001, or DS5340. For applications requiring switching from the VCC inputs to the VBAT input when VCC begins falling out of tolerance, any of the Dallas Semiconductor devices listed in Table 1 can provide the DS1336 with the required switching input. A typical application is shown in Figure 1. For applications where switching between VCC and VBAT must occur at a voltage level such that VCC is still greater than VBAT, the OUT5 pin is recommended as it provides a diode path which will provide for a gradual transition between VCC and VBAT. OUT5 can be tied to the other OUTPUT pins to provide a gradual transition for all five current paths. In applications where tri-state switching is desired, OUT5 should be omitted. Only the PF/ PF pin is required for switching. In cases where the PF input will not be used, it should be connected to GND. When either PF or PF is active, either of the VBAT0X outputs is available, although they should not be tied together (Figure 2, "DS1336 Block Diagram"). VBAT01 is recommended for sensitive applications such as providing backup current to timekeepers, because its diode isolated path provides for increased protection. VBAT02 is not recommended for applications where it would be tied to an OUTPUT pin supplying a voltage greater than that of the backup battery because VBAT02 is not a diode isolated current path. TYPICAL APPLICATION Figure 1 2 of 6 DS1336 DS1336 BLOCK DIAGRAM Figure 2 3 of 6 DS1336 DALLAS SEMICONDUCTOR DEVICES WHICH PROVIDE PF OR PF INPUT TO NIL Table 1 DEVICE SWITCH > VBAT DS1211 DEVICE SWITCH > VBAT SWITCH AT VBAT X DS1238 X X DS1212 X DS1239 X X DS1231 X DS1259 X DS1232 X DS1260 X DS1233 X DS1610 X DS1632 X DS1233A SWITCH AT VBAT X DS1233D X DS1833 X DS1234 X DS5001 X X DS1236 X DS5340 X X DS1237 X X 4 of 6 DS1336 ABSOLUTE MAXIMUM RATINGS* Voltage on Any Pin Relative to Ground Operating Temperature Storage Temperature Soldering Temperature -0.3V to +7.0V 0C to 70C -55C to +125C 260C 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. DC OPERATING CONDITIONS PARAMETER Supply Voltage Supply Current Supply Current Input Low Voltage Input High Voltage Current Output VCC=VCC1, PF=0, PF =1 Current Output VCC=0, PF=1, PF =0 Current, Forward Bias of VCC5 Diode Off Impedance Off Impedance On Impedance On Impedance SYMBOL VCC1 ICC1 ICC2 VIL VIH (tA = 0C to 70C; VCC = 5V 10%) MAX 5.5 1.0 100 0.8 VCC UNITS V mA nA V V NOTES 1 ICCO 300 mA 2 IBAT01-2 4.0 mA 4 IFB 20 mA 0.7 50 M M ROFF1 ROFF2 RON1 RON2 MIN 3.0 2.0 5.0 10 AC CHARACTERISTICS PARAMETER Propagation Delay Switch Delay Power-fail Switch Delay Power-on Capacitance PF, PF TYP 5.0 0.25 50 3 1 1 5 6 7 8 (tA = 0C to 70C; VCC = 5V 10%) SYMBOL tPD tPF tPON CI MIN TYP 10 100 MAX 100 7 NOTES: 1. All voltages referenced to ground. 2. ICCO with a voltage drop of 0.2 volts from any VCCO output. 3. VCC=0, VBATIN=3.0 volts. 4. VBAT01 with a voltage drop of 1.0 volts. 5. ROFF1 applies to VCCO1, 2, 3, 4. 6. ROFF2 applies to VBATO1, 2. 5 of 6 UNITS ns ns ns pF NOTES 9 DS1336 7. Applies to VCCO1-5, 300 mA. 8. Applies to VBATO1-2, 4 mA. 9. VCCI3 to VCCO3 delay when used as chip enable control for write protection of a memory device. In this application a current 8 mA source current on VCCI3 with 50 pF load on VCCO3 can be accommodated. 6 of 6