Output Stage Protection

The output stage is protected against overvoltage, short

circuit and thermal runaway conditions (Figure 1).

Figure 1. Typical Circuit Waveforms for Output Stage Protection.

If the input voltage rises above 30V (e.g. load dump), the out-

put shuts down. This response protects the internal circuitry

and enables the IC to survive unexpected voltage transients.

Should the junction temperature of the power device exceed

180ûC (typ) the load current capability is reduced thereby

preventing thermal overload. This thermal management

function is an effective means to prevent die overheating

since the load current is the principle heat source in the IC.

The CS8101 contains two microprocessor compatible con-

trol functions:

and

(Figure 2).

Figure 2. Circuit Waveform

Function

The

function switches the output transistor ON

and OFF. When the voltage on the

lead exceeds

1.4V typ, the output pass transistor turns off, leaving a

high impedance facing the load. The IC will remain in

Sleep mode, drawing only 50µA, until the voltage on this

input drops below the

threshold.

Function

A

signal (low voltage) is generated as the IC pow-

lower than 300mV below the regulated output voltage. A

hysteresis of 50mV is included in the function to minimize

oscillations.

The

output is an open collector NPN transistor,

controlled by a low voltage detection circuit. The circuit is

functionally independent of the rest of the IC thereby

guaranteeing that the

as 1V.

RESET

RESET

RESET

RESET

ENABLE

ENABLE

ENABLE

ENABLE

(1) = NO RESET DELAY CAPACITOR

(2) = WITH RESET DELAY CAPACITOR

ENABLE

(1)

(2)

H

RESET

RESET

ENABLE

Regulator Control Functions

IOUT

VOUT

VIN

Load

Dump

Short

Circuit

Current

Limit

> 30V

Voltage Reference and Output Circuitry

3

Package Lead Description

PACKAGE LEAD #

LEAD SYMBOL

FUNCTION

Circuit Description

8 Lead

20 Lead SOIC

5 Lead

SOIC

(Internally Fused Leads)

TO-220

819

5

Input voltage.

120

1

5V, ±2%, 100mA output.

3

1

2

Logic level switches output off when toggled HIGH.

4

4,5,6,7

3

Gnd

Ground. All Gnd leads must be connected to Ground.

14,15,16,17

5

10

4

Kelvin connection which allows remote sensing of out-

put voltage for improved regulation. If remote sensing

6,7

2,3,8,9,11,12,13,18

NC

No Connection.

RESET

ENABLE