Outline
This IC is a system reset IC developed using the CMOS process. Super low consumption current of 0.25μA typ. has been achieved through use of the CMOS process. Also, detection voltage is high precision detection of ±2%.

Features
*Super low consumption current 0.25μA typ. (when VDD = Vs + 1V)
*High precision detection voltage ±2%
*Hysteresis characteristic 5% typ.
*Operating range 0.95 ~ 10V
*Wide operating temperature range -30 ~ +85°C
*Detection voltage 2 ~ 6V (0.1V step)

Applications
*Microcomputer, CPU, MPU reset circuits
*Logic circuit reset circuits
*Battery voltage check circuits
*Back-up circuit switching circuits
*Level detection circuits

PST3120, PST3220, PST3320, PST3420

Outline
This open drain output system reset IC, developed using the CMOS process. Super low consumption current of 1.0μA typ. (PST3810 ~ PST3819) has been achieved through use of the CMOS process. Also, detection voltage is high precision detection of ±2%.

Features
*Super low consumption current 1.0μA typ. (when VDD = (-VDET) + 2.0V) PST3810 ~ PST3819
*High precision detection voltage ±2%
*Operating range 0.7 ~ 10V
*Wide operating temperature range -30 ~ +85°C
*Detection voltage 0.9 ~ 6.0V (0.1V step)

Applications
*Microcomputer, CPU, MPU reset circuits
*Logic circuit reset circuits
*Battery voltage check circuits
*Back-up circuit switching circuits
*Level detection circuits

PST3809, PST3810, PST3811, PST3812, PST3813, PST3814, PST3815, PST3816

Description
The IMP1233D supply voltage monitor is an improved, low-power replacement for the Dallas Semiconductor DS1233D. Maximum supply current over temperature is a low 20μA, representing over 60 percent lower power as compared to the DS1233D.
The IMP1233D issues an active LOW reset signal whenever the monitored supply is out-of-tolerance. A precision reference and comparator circuit monitor power supply (VCC) level. Tolerance level options are 5-,10- and 15-percent. When an out-of-tolerance condition is detected, an internal power-fail signal is generated which forces an active LOW reset signal. After VCC returns to an in-tolerance condition, the reset signal remains active for 350ms to allow the power supply and system microprocessor to stabilize.
The IMP1233D is designed with a open-drain output stage and operates over the extended industrial temperature range. Devices are available in compact surface mount SOT-223 packages.
Other low power products in this family include the IMP1810/11/12/15/16/17 and IMP1233M.

Key Features
*Improved Dallas DS1233D replacement
-Over 60% lower maximum supply current
*Low Supply Current
-20μA maximum (5.5V)
-15μA maximum (3.6V)
*Automatically restarts a microprocessor after power failure
*350ms reset delay after VCC returns to an in-tolerance condition
*Active LOW power-up reset, 5kΩ internal pull-up
*Precision temperature-compensated voltage reference and comparator
*Eliminates external components
*Motorola 68xxx and HC16 compatible
*Compact surface mount SOT-223 package
*Operating temperature –40°C to +85°C

Applications
*Set-top boxes
*Cellular phones
*PDAs
*Energy management systems
*Embedded control systems
*Printers
*Single board computers

IMP1233DZ-5/T, IMP1233DZ-10/T, IMP1233DZ-15/T

DESCRIPTION
The TK119xx series are low power, linear regulators with built-in electronic switches. Built-in voltage comparators provide a reset logic ”low” level whenever the input or output voltage falls outside internally preset limits. The internal electronic switch can be controlled by CMOS or TLL levels. The device is in the “off” state when the control pin is biased “high”.
An internal PNP pass-transistor is used in order to achieve low dropout voltage (typically 200 mV at 50 mA load current). The device has very low quiescent current (130 mA) in the “on” mode with no load and 2 mA with 30 mA load. The quiescent current is typically 4 mA at 60 mA load. The current consumption in the “off” mode is 65 mA.
An internal thermal shutdown circuit limits the junction temperature to below 150 oC. The load current is internally monitored and the device will shut down (no load current) in the presence of a short circuit at the output. The output noise is very low at 100 dB down from VOUT when an external noise bypass capacitor is used. The TK119xx is available in a miniature SOT-23L surface mount package.

FEATURES
*Very Low Dropout Voltage
*Reset Output for Microprocessor
*Very Low Quiescent Current (No Load)
*Internal Thermal/Overload Shutdown
*Low Noise Voltage
*Input and Output Voltage Sense
*± 2.5 % Output Voltage Accuracy
*CMOS or TTL On/Off Control
*High Speed On/Off Transient (50 ms typ.)

FEATURES
*Battery Powered Systems
*Cellular Telephones
*Pagers
*Personal Communications Equipment
*Portable Instrumentation
*Portable Consumer Equipment
*Radio Control Systems
*Toys
*Low Voltage Systems

TK11922, TK11927, TK11930, TK11932, TK11935, TK11940, TK11948, TK11950

Outline
These ICs were developed for STATIC-RAM (S-RAM) battery back-up, and have built-in switching circuit for main power supply and battery, back-up timing circuit and battery checker.
Power ON/OFF and momentary power interruptions can damage S-RAM data on equipment that contains an S-RAM. These ICs switch the S-RAM to back-up mode (CS signal makes S-RAM CE pin low and CE pin high)
when power supply voltage goes below a set voltage (detection voltage 4.2V typ., variable), preventing damage to data. Further, when power supply voltage drops, these ICs switch from main power supply to battery back-up (switching voltage 3.3V typ.). Then, when power supply voltage rises, they first switch the SRAM from battery back-up state to main power supply (switching voltage 3.3V typ.), and from back-up mode to normal mode (CS signal makes S-RAM CE pin high and CE pin low). These signal processes provide reliable protection against data damage. The CS signal also can absorb power supply chattering and roughness through the external capacitor.
There is a built-in battery checker to monitor the back-up battery voltage, and this circuit is turned ON/OFF by the control pin.

Features
*Battery back-up
-Low IC current consumption (loss current) 0.3μA typ.
-Drop voltage inside IC (input/output voltage difference) IO=10μA 0.2V typ.
-Reverse current (reverse leak current) 0.1μA max.
*Normal operation
MM1027
-Drop voltage inside IC (input/output voltage difference) IO=70mA 0.2V typ.
-Output voltage VCC=5V IO=10mA 4.8V typ.
-Current consumption D.CONT OPEN 3.0mA max.
-External transistor drive current 25mA typ.
MM1081
-Drop voltage inside IC (input/output voltage difference) IO=120mA 0.25V typ.
-Output voltage VCC=5V IO=120mA 4.75V typ.
-Current consumption 350μA max.
-External transistor drive current (for output current increase) 25mA typ.
-TC source current 3.0μA typ.
*Battery-Vcc switching voltage 3.3V typ.
*Detection voltage (CS, CS) variable 4.2V typ.
*Battery checker 1
-X type 2.70V typ.
-N type 2.50V typ.
*Battery checker 2
-X type 2.55V typ.
-N type 2.35V typ.

Applications
*IC memory cards (RAM cards)
*PCs, word processors
*Fax machines, photocopiers, other office equipment
*Other equipment with S-RAMs (equipment requiring back-up)

MM1081, MM1027XV, MM1027NV, MM1081XV, MM1027XF, MM1027NF, MM1027XD

DESCRIPTION
 The CAT1232LP and CAT1832 microprocessor supervisors can halt and restart a “hung-up” or “stalled” microprocessor, restart a microprocessor after a power failure, and debounce a manual/push-button microprocessor reset switch.
The devices are drop in replacements for the Maxim/Dallas Semiconductor DS1232LP and DS1832 supervisors Precision reference and comparator circuits monitor the 5V or 3.3V system power supply voltage, VCC.
During power-up or when the power supply falls outside selectable tolerance limits, both the RESET and RESET¯¯¯¯¯¯ become active.
After the power supply voltage rises above the RESET threshold voltage, the reset signals remain active for a minimum of 250ms, allowing the power supply and system processor to stabilize.
The trip-point tolerance input, TOL, selects the trip level tolerance to be either 5% or 10% for the CAT1232LP 5V supply and 10% or 20% for the CAT1832 3.3V supply.
Each device has a push-pull, active HIGH reset output.
The CAT1232LP also has an open drain, active LOW reset output while the CAT1832 also has a push-pull, active LOW reset output.
A debounced manual reset input activates the reset outputs and holds them active for a minimum period of 250ms after being released.
Also included is a watchdog timer to reset a microprocessor that has stopped due to a software or hardware failure.
Three watchdog time-out periods are selectable: 150ms, 600ms and 1.2s. If the ST¯¯ input is not strobed low before the watchdog time out period expires, the reset signals become active for a minimum of 250ms.

FEATURES
* Selectable reset voltage tolerance
- CAT1232LP for 5V supply
- CAT1832 for 3.3V supply
* Selectable watchdog period: 150ms, 600ms or 1.2s
* Two reset outputs
- Active high, push-pull reset output
- Active low, open-drain reset output (CAT1232LP)
- Active low, push-pull reset output (CAT1832)
* Debounced manual push-button reset
* Compact SOIC and MSOP packages

APPLICATIONS
* Microprocessor Systems
* Portable Equipment
* Controllers
* Single Board Computers
* Instrumentations
* Telecommunications

CAT1232LPL-G
CAT1232LPV-GT3
CAT1232LPZ-GT3
CAT1232LPW-T2

Outline
This IC is a low-reset type system reset IC and in a variety of CPU systems and other logic systems, to detect supply voltage and reset the system accurately when the power is turned on or interrupted.
It includes a high-precision voltage detection function with ultra-low current consumption and is ideal for voltage check circuits for products using a battery.

Features
1. High-precision voltage detection Vs±2% max.
2. Ultra-low current consumption ICCH=2µA typ. ICCL=3µA typ.
3. Low operating limit voltage 0.65V typ.
4. Hysteresis voltage provided for detection voltage 50mV typ.
5. Large output current during power-on 30mA typ.
6. Detection voltage can be selected as desired within a range of 1.9 to 4.6V
by 0.1V step, as indicated below.

Applications
1. Reset circuits for microcomputers, CPUs and MPUs
2. Reset circuits for logic circuits
3. Battery voltage check circuits
4. Back-up power supply switching circuits
5. Level detection circuits

PST7020 PST7021 PST7022 PST7023 PST7024 PST7025 PST7026 PST7027 PST7028 PST7029
PST7030 PST7031 PST7032 PST7033 PST7034 PST7035 PST7036 PST7037 PST7038 PST7039
PST7040 PST7041 PST7042 PST7043 PST7044 PST7045 PST7046