CS8121

Features:

`5V ± 4% Output Voltage
`Low Dropout Voltage  (1.2V @ 1A)
`Low Quiescent Current (4mA @ IOUT = 1A)
`µP Compatible Control
Functions
RESET
ENABLE
`Low Current Sleep Mode IQ = 250µA
`Fault Protection  Thermal Shutdown Short Circuit  60V Peak Transient  Voltage


Pinout




Specifications

DC Input Voltage .....................................................................................................................-0.7 to 26V
Peak Transient Voltage (46V Load Dump)............................................................................................60V
Output Current ..............................................................................................................Internally Limited
Electrostatic Discharge (Human Body Model).......................................................................................2kV
Operating, Temperature .....................................................................................................-40C to 125
Junction Temperature..........................................................................................................-40C to 150
Storage Temperatures........................................................................................................55 to 150
Lead Temperature Soldering
Wave Solder (through hole styles only) .............................................................10 sec. max, 260 peak
Reflow (SMD styles only) ...............................................................60 sec. max above 183, 230 peak


Description

The CS8121 is a 5V, 1A precision linear regulator with two microprocessor compatible control functions and protection circuitry included on chip. The composite NPN-PNP output pass transistor assures a lower dropout voltage (1.2V @ 1A) without requiring excessive supply current (4mA).

The CS8121Õs two logic control functions make this regulator well suited to applications requiring microprocessorbased control at the board or module level.ENABLE controls the output stage. A high voltage (>2.9V) on the ENABLE lead turns off the regulator Õs pass transistor and sends the IC into Sleep mode where it draws only 250µA. RESET sends a RESET signal when the IC is powering up or whenever the output voltage falls out of regulation. The RESET signal is valid down to VOUT = 1V.

The CS8121 design optimizes supply rejection by switching the internal bandgap reference from the supply input to the regulator output as soon as the nominal output voltage is achieved. Additional on chip filtering enhances rejection of high frequency transients on all external leads.

The CS8121 is fault protected against short circuit, over voltage and thermal runaway conditions.