May, 1997 TOKO, Inc.

Page 7

TK113xxB

DEFINITION AND EXPLANATION OF TECHNICAL TERMS

OUTPUT VOLTAGE (V

The output voltage is specified with V

and I

DROPOUT VOLTAGE (V

The dropout voltage is the difference between the input

voltage and the output voltage at which point the regulator

starts to fall out of regulation. Below this value, the output

voltage will fall as the input voltage is reduced.

It is

dependent upon the load current and the junction tempera-

ture.

OUTPUT CURRENT (I

The rated output current is specified under the condition

where the output voltage drops 0.3 V below the value

specified with I

V, and the current is pulsed to minimize temperature effect.

CONTINUOUS OUTPUT CURRENT (I

Normal operated output current. This is limited by package

power dissipation.

PULSE OUTPUT CURRENT (I

Max pulsewidth 5ms, Duty cycle 12.5%: pulse load only

LINE REGULATION (LINE REG)

Line Regulation is the ability of the regulator to maintain a

constant output voltage as the input voltage changes. The

line regulation is specified as the input voltage is changed

from V

LOAD REGULATION (LOAD REG)

Load regulation is the ability of the regulator to maintain a

constant output voltage as the load current changes. It is

a pulsed measurement to minimize temperature effects

with the input voltage set to V

The load

regulation is specified under two output current step condi-

tions of 1 mA to 60 mA and 1 mA to 100 mA.

QUIESCENT CURRENT (IQ)

The quiescent current is the current which flows through

the ground terminal under no load conditions (I

.

RIPPLE REJECTION RATIO

Ripple rejection is the ability of the regulator to attenuate

the ripple content of the input voltage at the output. It is

specified with 100 mVrms, 400 Hz superimposed on the

input voltage, where V

capacitor is set to 10

µF, the noise bypass capacitor is set

to 0.1

µF, and the load current is set to 30 mA. Ripple

rejection is the ratio of the ripple content of the output vs. the

input and is expressed in dB.

STANDBY CURRENT

Standby current is the current which flows into the regulator

when the output is turned off by the control function (V

CONT

= V

device.)

SENSOR CIRCUIT

Over current sensor

The overcurrent sensor protects the device in the event

that the output is shorted to ground.

Thermal sensor

The thermal sensor protects the device in the event

that the junction temperature exceeds the safe value

(T

external heat, excessive power dissipation caused by

large input to output voltage drops, or excessive output

current. The regulator will shut off when the tempera-

ture exceeds the safe value. As the junction tempera-

tures decrease, the regulator will begin to operate

again. Under sustained fault conditions, the regulator

output will oscillate as the device turns off then resets.

Damage may occur to the device under extreme fault

conditions.

Reverse Voltage Protection

Reverse voltage protection prevents damage due to

the output voltage being higher than the input voltage.

This fault condition can occur when the output capaci-

tor remains charged and the input is reduced to zero,

or when an external voltage higher than the input

voltage is applied to the output side.