Description The device CMOS Dynamic RAM organized as 4,194,304 words x 4 bits with extended data out access mode. It is fabricated with an advanced submicron CMOS technology and designed to operate from a single 3.3V oniy power supply. Low voltage operation is more suitable to be used on battery backup, portable elec tronic application. lt is packaged in JEDEC standard 26/24-pin plastic SOJ or TSOP(II).
Features • Single 3.3V(±10%) only power supply • High speed tRAC acess time: 50/60ns • Low power dissipation - Active mode : 432/396 mW (Mas) - Standby mode: 0.54 mW (Mas) • Extended - data - out(EDO) page mode access • I/O level: CMOS level (Vcc = 3.3V) • 2048 refresh cycle in 32 ms(Std.) or 128 ms(S-version) • 4 refresh modesh: - RAS only refresh - CAS - before - RAS refresh - Hidden refresh - Self-refresh(S-version)
DESCRIPTION The LTC®4110 is a complete single chip, high efficiency, fl yback battery charge and discharge manager with automatic switchover between the input supply and the backup battery or super capacitor. The IC provides four modes of operation: battery backup, battery charge, battery calibration and shutdown. battery backup and battery charge are automatic standalone modes, while the optional calibration mode requires a CPU host to communicate over an SMBus. During calibration the fl yback charger is used in reverse to discharge the battery with a programmable constant current into the system load eliminating heat generation.
FEATURES ■ Complete Backup battery Manager for Li-Ion/ Polymer, Lead Acid, NiMH/NiCd Batteries and Super Capacitors ■ Charge and Discharge battery with voltages Above and BeLow the Input Supply voltage ■ “No Heat” battery Calibration Discharge Using System Load ■ Automatic battery Backup with Input Supply Removal Using PowerPath™ Control ■ Standalone for Li-Ion/Polymer, SLA, and Supercaps ■ Optional SMBus/I2C Support AlLows battery Capacity Calibration operation with Host ■ Over- and Under-battery voltage Protection ■ Adjustable battery Float voltage ■ Precision Charge voltage ±0.5% ■ Programmable Charge/Calibration Current Up to 3A with ±3% Accuracy ■ Optional Temperature Qualifi ed Charging ■ Wide Backup battery Supply Range: 2.7V to 19V ■ Wide Input Supply Range: 4.5V to 19V ■ 38-Lead (5mm × 7mm) QFN Package
APPLICATIONS ■ Backup battery Systems ■ Server Memory Backup ■ Medical Equipment ■ High Reliability Systems
General Description The MAX8568A/MAX8568B backup-battery-management ICs are complete charging and backup switchover control solutions for PDAs, Smart Phones, and other smart portable devices. They charge both NiMH and rechargeable lithium battery types and feature programmable charge current and termination voltage. Separate optimized charge algorithms for both lithium and NiMH cells are included on-chip. The MAX8568A/MAX8568B also manage backup switchover from a primary power source. An accurate on chip voltage detector monitors the main supply and backs up two system supplies (typically I/O and memory) when main power falls. On-chip drivers switch external MOSFETs to disconnect the main supply from the system loads so the backup source is not drained. Low-voltage backup cells can be stepped up by an on chip synchronous-rectified, Low-quiescent-current boost converter. Additionally, a Low-quiescent-current LDO generates a second backup voltage. The MAX8568A LDO is preset to 2.5V while the MAX8568B LDO is preset to 1.8V. Both devices are supplied in 16-pin 3mm x 3mm thin QFN packages rated for -40°C to +85°C operation.
Features ♦ Automatically Manage All Backup Switchover Functions ♦ Charge Both NiMH and Rechargeable Lithium Backup Batteries ♦ On-Chip battery Boost Converter for 1-Cell NiMH ♦ Two Backup Output voltages ♦ Programmable Charge Current ♦ Programmable Charge voltage Limit ♦ Low 17µA Operating Current in Backup Mode ♦ Eliminate Many Discrete Components ♦ Tiny 3mm x 3mm Thin QFN Package
Applications PDAs and PDA Phones Smart Phones DSCs and DVCs Palmtops and Wireless Handhelds Internet Appliances and Web-Books
The LTC®1558 is a backup battery controller that provides all the functions necessary to implement a backup power supply using a single NiCd cell. It includes a 1.2V boost converter, an intelligent 2-stage battery charger, auto matic backup switching and a microprocessor reset generator. The boost converter uses a synchronous switching architecture to achieve a typical efficiency of 70%, ensuring maximum backup lifetime from a small NiCd cell.
■ Complete battery Backup System in an SO-8, 16-Pin GN or SO Package
■ Generates Adjustable Backup voltage from a Single 1.2V NiCd Button Cell
■ Automatic Main Supply to Backup Switching
■ Minimum 100mW Output Power
■ Automatic Fast Recharge of NiCd battery
■ Programmable NiCd Trickle Charge Current
■ Smart NiCd Charger Minimizes Recharge Time and Maximizes System Efficiency After Backup
■ On-Chip Power-On Reset
■ Pushbutton Reset Input
■ Reset Assertion Guaranteed at VCC= 1V
■ Short-Circuit Protection
■ Thermal Limiting
DESCRIPTION The LTC®1559 is a backup battery controller that provides all the functions necessary to implement a backup 3.3V or 5V power supply using a single NiCd cell. It includes a 1.2V to 3.07V/4.63V boost converter, an intelligent 2-stage battery charger, automatic backup switching and a microprocessor reset generator. The boost converter uses a synchronous switching architecture to achieve a typical efficiency of 70%, ensuring maximum backup lifetime from a small NiCd cell.
FEATURES ■ Complete battery Backup System in an SO-8, 16-Pin GN or SO Package ■ Generates Fixed Backup voltage (3.07V/4.63V) from a Single 1.2V NiCd Button Cell ■ Automatic Main Supply to Backup Switching ■ Minimum 100mW Output Power ■ Automatic Fast Recharge of NiCd battery ■ Programmable NiCd Trickle Charge Current ■ Smart NiCd Charger Minimizes Recharge Time and Maximizes System Efficiency After Backup ■ Onboard Power-Up and Push-Button Reset Generator ■ Performs VCC Supervisory Functions ■ Reset Assertion Guaranteed at VCC = 1V ■ Short-Circuit Protection ■ Thermal Limiting
DESCRIPTION The LT ®1239 is a micropower backup battery management system for portable computers and instrumentation. It contains two regulators for regulating the battery voltage and memory voltage and a comparator for switching between main power and backup power. The first regulator provides a constant voltage charge for the backup batteries and is adjustable from 3.75V up to 20V. An equalization amplifier combined with the first regulator provides precision charge equalization for a 2-cell lithium-ion system. A second regulator with 4.85V output providesaregulatedbackupbatteryvoltagetothememory when main power is lost. The second regulator also isolates the backup battery from the main 5V supply during normal operation when the memory is being powered by the 5V supply.
FEATURES ■ Micropower operation (IQ = 20μA) ■ Adjustable Regulator for battery Charging ■ 4.85V Regulator for battery Regulation ■ Cell voltage Equalization in 2-Cell Systems ■ Low-battery Detector Protects Lithium Cells ■ Comparator for Automatic Power Switching ■ Shutdown ■ Output Current Sensing ■ Current and Thermal Limiting ■ Reverse Output Protection ■ 16-Pin SO Package ■ Operates on 7V to 30V Input
APPLICATIONS ■ Backup battery Management Systems for Portable Computers ■ Lithium-Ion Backup Systems ■ NiCd Backup Systems
The M62021 is a system IC that controls the memory backup function of microcomputer (internal RAM).
The IC outputs reset signals (RES/RES) to a microcomputer at power-down and power failure. It also shifts the power supply to RAM from main to backup, outputs a signal (CS) that invokes standby mode, and alters RAM to backup circuit mode.
• Built-in switch for selection between main power supply and backup power supply to RAM.
• Small difference between input and output voltage (IOUT= 80 mA, VIN = 5 V) 0.2 V Typ
• Detection voltage (power supply monitor voltage) 4.40 V ±0.2 V
• Chip select signal output (CS)
• Two channels of reset outputs (RES/RES)
• Power on reset circuit built-in
• Delay time variable by an external capacitance connected to Ct pin
• Facilitates to form backup function with a few number of components
• Power supply control systems for memory backup of microcomputer system and SRAM boards with built-in backup function that require switching between external power supply and battery.
General Description The MAX16016/MAX16020/MAX16021 supervisory circuits monitor power supplies, provide battery-backup control, and chip-enable (CE) gating to write protect memory in microprocessor (µP)-based systems. These Low-power devices improve system reliability by providing several supervisory functions in a small, single integrated solution.
Features ♦ System Monitoring for 5V, 3.3V, 3V, 2.5V, or 1.8V Power-Supply voltages ♦ 1.53V to 5.5V Operating voltage Range ♦ Low 1.2µA Supply Current (0.25µA in battery Backup Mode) ♦ 145ms (min) Reset Timeout Period ♦ battery Freshness Seal ♦ On-Board Gating of CE Signals, 1.5ns Propagation Delay (MAX16020/MAX16021) ♦ Debounced Manual Reset Input ♦ Watchdog Timer, 1.2s (typ) Timeout ♦ Power-Fail Comparator and Low-Line Indicator for Monitoring voltages Down to 0.6V ♦ battery-On, battery-OK, and battery Test Indicators ♦ Small 10-Pin TDFN or 16-Pin TQFN Packages ♦ UL®-Certified to Conform to IEC 60950-1
Applications Main/Backup Power for RTCs, CMOS Memories Industrial Control GPS Systems Set-Top Boxes Point-of-Sale Equipment Portable/battery Equipment
BD4201FV is a battery backup IC. Switch that detect battery voltage and switch into back up power supply and 3-channel regulator are incorporated into a single chip. Current consumption is 15µA (Max.). This IC is perfect for portable appliances.
zFeatures 1) Low quiescent current Normal operation < 15.0µA Max. Backup mode < 2.1µA Max. 2) 3 high accurate voltage regulators 3) Low dropout voltage, and high accurate voltage detectors (CS, RESET) 4) Control circuit; Backup 5) Special sequence; For shifting to the backup mode. It need to make main battery over +Vdet1 once.
General Description The MAX703/MAX704 microprocessor (μP) supervisory circuits reduce the complexity and number of components required for power-supply monitoring and battery control functions in μP systems. These devices significantly improve system reliability and accuracy compared to that obtained with separate ICs or discrete components. The MAX703/MAX704 are available in 8-pin DIP and SO packages and provide four functions:
1) An active-Low reset during power-up, power-down, and brownout conditions. 2) battery-backup switching for CMOS RAM, CMOS μPs, or other Low-power logic circuitry. 3) A 1.25V threshold detector for power-fail warning, Low-battery detection, or for monitoring a power supply other than +5V. 4) An active-Low manual reset input.
The MAX703 and MAX704 differ only in their supplyvolt age monitor levels. The MAX703 generates a reset when the supply drops beLow 4.65V, while the MAX704 gener ates a reset beLow 4.40V.
Features ● battery-Backup Power Switching ● Precision Supply-voltage Monitor • 4.65V (MAX703) • 4.40V (MAX704) ● 200ms Reset Pulse Width ● Debounced TTL/CMOS-Compatible Manual Reset Input ● 200μA Quiescent Current ● 50nA Quiescent Current in battery-Backup Mode ● voltage Monitor for Power-Fail or Low-battery Warning ● 8-Pin DIP and SO Packages ● Guaranteed RESET Assertion to VCC = 1V