LT1579CS8-3.3 Linear Technology, LT1579CS8-3.3 Datasheet - Page 9

• Manufacturer Part Number: LT1579CS8-3.3
• Description: IC LDO REG SMART DUAL 3.3V 8SOIC
• Manufacturer: Linear Technology

Specifications of LT1579CS8-3.3

• Function: Back-Up Management
• Battery Type: Smart Batteries
• Operating Temperature: 0°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 8-SOIC (0.154", 3.90mm Width)
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

TYPICAL PERFORMANCE CHARACTERISTICS
PIN
V
bypass capacitor is required on this pin if the device is
more than six inches away from the main input filter
capacitor. In general, the output impedance of a battery
rises with frequency, so it is advisable to include a bypass
capacitor in battery-powered circuits. A bypass capacitor
in the range of 1 F to 10 F is sufficient.
V
A bypass capacitor is required on this pin if the device is
more than six inches away from the main input filter
capacitor. In general, the output impedance of a battery
IN1
IN2
100
90
80
70
60
50
40
30
20
10
U
0
: The primary power source is connected to V
: The secondary power source is connected to V
10
Ripple Rejection
I
V
LOAD
FUNCTIONS
IN
= 6V + 50mV
= 150mA
100
U
FREQUENCY (Hz)
–100
– 50
100
100
1k
RMS
50
75
50
25
0
0
LT1579-5 Transient Response
0
RIPPLE
U
50
10k
100
C
TANTALUM
C
OUT
TANTALUM
OUT
V
C
C
SOLID
150
W
SOLID
IN
IN
OUT
100k
= 4.7 F
= 6V
= 1 F CERAMIC
= 47 F
= 4.7 F TANTALUM
200
1579 G30
TIME ( s)
U
250
1M
300
350
–10
–12
–16
–14
400
– 6
– 8
– 2
– 4
0
– 50
Load Regulation
450
1579 G33
LT1579
LT1579-5
– 25
500
IN1
0
IN2
TEMPERATURE ( C)
. A
.
25
I
LOAD
rises with frequency, so it is advisable to include a bypass
capacitor in battery-powered circuits. A bypass capacitor
in the range of 1 F to 10 F is sufficient.
OUT: The output supplies power to the load. A minimum
output capacitor of 4.7 F is required to prevent oscilla-
tions. Larger output capacitors will be required for appli-
cations with large transient loads to limit peak voltage
transients.
ADJ: For the adjustable LT1579, this is the input to the
error amplifier. This pin is internally clamped to 7V and
– 0.6V (one V
50
= 1mA TO 300mA
LT1579-3.3
75
LT1579-3
100
–100
– 50
100
300
200
100
50
1579 G40
0
LT1579-5 Transient Response
0
125
BE
0.1
). It has a bias current of 6nA which flows
0.2
50mV/DIV
V
C
C
V
IN
IN
OUT
0.3
IN1
V
= 6V
= 1 F CERAMIC
OUT
6V
5V
= 22 F TANTALUM
0.4
UNPLUG
TIME (ms)
V
LT1579-5 “Hot” Plugging and
Unplugging Transient Response
IN1
0.5
0.6
0.7
0.8
0.9
1579 G34
1,0
LT1579
REPLACE
V
IN1
9