ON Semiconductor

The CS8101 is a precision 5V micropower voltage regulator with very low quiescent current (70uA typ at 100uA load). The 5V output is accurate within +/-2% and supplies 100mA of load current with a typical dropout voltage of only 400mV. Microprocessor control logic includes an ENABLEbar input and an active RESETbar. This combination of low quiescent current, outstanding regulator performance and control logic makes the CS8101 ideal for any battery operated, microprocessor controlled equipment.The active RESETbar circuit includes hysteresis, and operates correctly at an output voltage as low as 1V. The RESETbar function is activated during the power up sequence or during normal operation if the output voltage drops outside the regulation limits by more than 200mV typ. The logic level compatible ENABLEbar input allows the user to put the regulator into a shutdown mode where it draws only 20uA typical of quiescent current.The regulator is protected against reverse battery, short circuit, over voltage, and thermal overload conditions. The device can withstand load dump transients making it suitable for use in automotive environments.The CS8101 is functionally equivalent to the National Semiconductor LP2951 series low current regulators.

The CS8126 is a low dropout, high current 5.0 V linear regulator. It is an improved replacement for the CS8156. Improvements include higher accuracy, tighter saturation control, better supply rejection, and enhanced RESETbar circuitry. Familiar PNP regulator features such as reverse battery protection, overvoltage shutdown, thermal shutdown, and current limit make the CS8126 suitable for use in automotive and battery operated equipment. Additional on-chip filtering has been included to enhance rejection of high frequency transients on all external leads.An active microprocessor RESET function is included on-chip with externally programmable delay time. During power- up, or after detection of any error in the regulated output, the RESET lead will remain in the low state for the duration of the delay. Types of errors include short circuit, low input voltage, overvoltage shutdown, thermal shutdown, or others that cause the output to become unregulated. This function is independent of the input voltage and will function correctly with an output voltage as low as 1.0 V. Hysteresis is included in both the reset and Delay comparators for enhanced noise immunity. A latching discharge circuit is used to discharge the Delay capacitor, even when triggered by a relatively short fault condition. This circuit improves upon the commonly used SCR structure by providing full capacitor discharge (0.2 V type).Note: The CS8126 is lead compatible with the LM2927 and LM2926.

The CS8129 is a precision 5V linear regulator capable of sourcing 750mA. The RESETbar threshold voltage has been lowered to 4.2V so that the regulator can be used with 4V microprocessors. The lower RESETbar threshold also permits operation under low battery conditions (5.5V plus a diode). The RESETbar's delay time is externally programmed using a discrete RC network. During power up, or when the output goes out of regulation, RESETbar remains in the low state for the duration of the delay. This function is independent of the input voltage and will function correctly as long as the output voltage remains at or above 1V. Hysteresis is included in the Delay and the RESETbar comparators to improve noise immunity. A latching discharge circuit is used to discharge the delay capacitor when it is triggered by a brief fault condition.The regulator is protected against a variety of fault conditions: i.e. reverse battery, overvoltage, short circuit and thermal runaway conditions. The regulator is protected against voltage transients ranging from -50V to +40V. Short circuit current is limited to 1.2A (typ).

The CS8151 is a precision 5.0 V, 100 mA micro-power voltage regulator with very low quiescent current (400 mA typical at 200 mA load). The 5.0 V output is accurate within +/-2% and supplies 100 mA of load current with a typical dropout voltage of 400 mV. Microprocessor control logic includes Watchdog, Wake Up and RESETbar. This unique combination of low quiescent current and full microprocessor control makes the CS8151 ideal for use in battery operated, microprocessor controlled equipment.The CS8151 Wake Up function brings the microprocessor out of Sleep mode. The microprocessor in turn, signals its Wake Up status back to the CS8151 by issuing a Watchdog signal.The Watchdog logic function monitors an input signal (WDI) from the microprocessor. The CS8151 responds to the falling edge of the Watchdog signal which it expects at least once during each wake-up period. When the correct Watchdog signal is received, a falling edge is issued on the wake-up signal line.RESETbar is independent of VINand operates correctly to an output voltage as low as 1.0 V. A RESETbar signal is issued in any of three situations. During power up the RESETbar is held low until the output voltage is in regulation. During operation if the output voltage shifts below the regulation limits, the RESETbar toggles low and remains low until proper output voltage regulation is restored. And finally, a RESETbar signal is issued if the regulator does not receive a Watchdog signal within the Wake Up period.The RESETbar pulse width, Wake Up signal frequency, and Wake Up delay time are all set by one external capacitor CDelay.The regulator is protected against short circuit, over voltage, and thermal runaway conditions. The device can withstand 74 volt peak transients, making it suitable for use in automotive environments.