Datasheet

LTC3823
4
3823fd
Current Sense Threshold
vs I
TH
Voltage
On-Time vs I
ON
Current On-Time vs V
ON
Voltage
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
PGOOD Output
ΔV
FBH
PGOOD Upper Threshold V
FB
Rising 8 11 14 %
ΔV
FBL
PGOOD Lower Threshold V
FB
Falling –8 –11 –14 %
ΔV
FB(HYS)
PGOOD Hysteresis V
FB
Returning 1.5 3 %
V
PGL
PGOOD Low Voltage I
PGOOD
= 5mA 0.15 0.4 V
Differential Sensing Amplifi er
A
DA
Gain
l
0.9965 1.000 1.0035 V/V
R
IN
Input Resistance Measured at V
OUTSENSE
+
Input 80 kΩ
V
OS
Input Offset Voltage V
OUTSENSE
+
= V
DIFFOUT
= 1.5V,
I
DIFFOUT
= 1mA
2mV
PSRR
OA
Power Supply Rejection Ratio 6V < V
IN
< 30V 90 dB
I
CL
Maximum Output Current 3mA
V
OUT(MAX)
Maximum Output Voltage I
DIFFOUT
= 300μA
l
3.775 4 V
GBW Gain Bandwidth Product I
DIFFOUT
= 1mA 3.5 MHz
Thermal Shutdown
T
SD
Shutdown Temperature Rising 170 °C
T
HYST
Thermal Hysteresis 15 °C
ELECTRICAL CHARACTERISTICS
The l denotes the specifi cations which apply over the full operating
temperature range, otherwise specifi cations are at T
A
= 25°C. V
IN
= 15V unless otherwise specifi ed.
Note 1: Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2: T
J
is calculated from the ambient temperature T
A
and power
dissipation P
D
according to the following formulas:
LTC3823GN: T
J
= T
A
+ (P
D
• 80°C/W)
LTC3823UH: T
J
= T
A
+ (P
D
• 34°C/W)
Note 3: The LTC3823 is tested in a feedback loop that servos V
FB
to
achieve a specifi ed error amplifi er output voltage (I
TH
).
Note 4: The LTC3823E is guaranteed to meet performance specifi cations
from 0°C to 85°C. Specifi cations over the –40°C to 85°C operating
temperature range are assured by design, characterization and correlation
with statistical process controls. The LTC3823I is guaranteed over the full
–40°C to 85°C operating temperature range.
I
TH
VOLTAGE (V)
0
–150
CURRENT SENSE THRESHOLD (mV)
–100
0
50
100
1
2
2.5
300
2823 G01
–50
0.5 1.5
150
200
250
V
RNG
= 2V
1.4V
1V
0.7V
0.5V
I
ON
CURRENT (μA)
10
ON-TIME (ns)
100
1000
10000
20 40 60 80
3823 G02
10010030507090
V
ON
= 0V
V
ON
VOLTAGE (V)
0
ON-TIME (ns)
800
700
600
500
400
300
200
100
0
4
3823 G03
123 53.50.5 1.5 2.5 4.5
I
ION
= 60μA
TYPICAL PERFORMANCE CHARACTERISTICS