LP3990

SNVS251J – MAY 2004 – REVISED SEPTEMBER 2014

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Electrical Characteristics

(1)(2) (continued)

Unless otherwise noted, VEN = 950 mV, VIN = VOUT + 1 V or VIN = 2 V, whichever is higher. CIN = 1 µF, IOUT = 1 mA, COUT =

0.47 µF.

PARAMETER

TEST CONDITIONS

MIN

TYP

MAX

UNIT

ENABLE CONTROL CHARACTERISTICS

VEN = 0 V (Output is disabled)

0.001

0.1

Maximum input current

TJ = 25°C

IEN

(8)

µA

at EN pin

VEN = 6 V

2.5

6

10

VIN = 2 V to 6 V

VIL

Low input threshold

VEN falling from ≥ VIH until the output is

0.4

disabled

V

VIN = 2 V to 6 V

VIH

High input threshold

VEN rising from ≤ VIL until the output is

0.95

enabled

(8)

ENABLE Pin has 1-M

Ω (typical) resistor connected to GND.

6.6 Output Capacitor, Recommended Specifications

(1)

PARAMETER

TEST CONDITIONS

MIN

TYP

MAX

UNIT

Capacitance(2)

0.7(3)

1

500

µF

COUT

Output capacitance

ESR

5

m

Ω

(1)

Unless otherwise specified, values and limits apply for TJ = 25°C.

(2)

The full operating conditions for the application should be considered when selecting a suitable capacitor to ensure that the minimum

value of capacitance is always met. Recommended capacitor type is X7R. However, dependent on application, X5R, Y5V, and Z5U can

also be used. (See Detailed Design Procedure.)

(3)

Limit applies over the full operating junction temperature range (TJ) of −40°C to 125°C.

6.7 Timing Requirements

MIN

NOM(1)

MAX(2)

UNIT

VOUT = 0.8 V

80

150

From VEN ↑ VIH to

TON

Turnon time (3)

VOUT 95% level

VOUT = 1.5 V

105

200

µs

(VIN(MIN) to 6 V)

VOUT = 3.3 V

175

250

Line transient response

Trise = Tfall = 30 µs

(3),

mV (pk-

8

16

(

ΔVOUT)

ΔVIN = 600 mV

pk)

Transient

Trise = Tfall = 1 µs

(3),

response

Load transient response

IOUT = 1 mA to 150 mA

55

100

mV

(

ΔVOUT)

COUT = 1 µF

(1)

Nom values apply for TJ = 25°C.

(2)

Maximum limits apply over the full operating junction temperature (TJ) range of −40°C to 125°C.

(3)

This electrical specification is verified by design.

6

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