LT3437 LINER [Linear Technology], LT3437 Datasheet - Page 3

• Manufacturer Part Number: LT3437
• Description: High Voltage 500mA, 200kHz Step-Down Switching Regulator with 100uA Quiescent Current
• Manufacturer: LINER [Linear Technology]

ELECTRICAL CHARACTERISTICS
temperature range, otherwise specifications are at T
C
SYMBOL
I
I
V
I
I
SW V
I
Note 1: Absolute Maximum Ratings are those values beyond which the life of
a device may be impaired.
Note 2: The LT3437EDD/LT3437EFE are guaranteed to meet performance
specifications from 0°C to 125°C junction temperature. Specifications over
the –40°C to 125°C operating junction temperature range are assured by
design, characterization and correlation with statistical process controls. The
LT3437IDD/LT3437IFE are guaranteed and tested over the full –40°C to
125°C operating junction temperature range.
Note 3: Minimum input voltage is defined as the voltage where switching
starts. Actual minimum input voltage to maintain a regulated output will
depend upon output voltage and load current. See Applications Information.
Note 4: Supply input current is the quiescent current drawn by the input
pin. Its typical value depends on the voltage on the BIAS pin and operating
state of the LT3437. With the BIAS pin at 0V, all of the quiescent current
required to operate the LT3437 will be provided by the V
BIAS voltage above its minimum input voltage, a portion of the total
quiescent current will be supplied by the BIAS pin. Supply sleep current is
BIASS
BIAS
FB
PK
CSS
REF
SS
/SYNC = 0V unless otherwise noted.
CESAT
PARAMETER
BIAS Sleep Current (Note 4)
BIAS Quiescent Current
Minimum Boost Voltage (Note 6)
Input Boost Current (Note 7)
Reference Voltage (V
FB Input Bias Current
EA Voltage Gain (Note 8)
EA Voltage g
EA Source Current
EA Sink Current
V
V
V
SW Current Limit
Switch Saturation Voltage
(Note 9)
Switching Frequency
Maximum Duty Cycle
Minimum SYNC Amplitude
SYNC Frequency Range
SYNC Input Impedance
C
C
C
C
SS
to SW g
Switching Threshold
High Clamp
Current Threshold (Note 10)
m
m
REF
)
IN
CONDITIONS
I
I
FB = 0V
pin. With the
SYNC = 2V
I
I
I
3.3V < V
dI(V
FB = 1.15V
FB = 1.35V
V
SW
SW
SW
SW
SW
J
SYNC
= 25°C. V
= 250mA
= 500mA
= 250mA
= 0.5A
= 0.25A
C
)= ±10µA
= 2V
The
VIN
< 80V
●
IN
denotes the specifications which apply over the full operating
= 12V, SHDN = 12V, BIAS = 5V, FB = 1.25V,
defined as the quiescent current during the “sleep” portion of Burst Mode
operation. See Applications Information for determining application supply
currents.
Note 5: Minimum BIAS voltage is the voltage on the BIAS pin when I
sourced into the pin.
Note 6: This is the minimum voltage across the boost capacitor needed to
guarantee full saturation of the internal power switch.
Note 7: Boost current is the current flowing into the BOOST pin with the pin
held 3.3V above input voltage. It flows only during switch on time.
Note 8: Gain is measured with a V
Note 9: Switch saturation voltage guaranteed by correlation to wafer level
measurements for DD package parts.
Note 10: The C
C
Soft-Start section in Applications Information.
SS
pin which results in an increase in sink current from the V
SS
threshold is defined as the value of current sourced into the
●
●
●
●
●
●
C
swing from 1.15V to 750mV.
1.225
MIN
500
170
240
1.5
15
15
4
0.75
1.25
1.75
TYP
150
900
650
500
650
200
400
200
1.8
1.5
35
11
50
30
95
50
10
8
1
LT3437
1.275
MAX
250
200
900
400
800
240
700
2.5
2.1
16
13
55
55
16
1
2
C
pin. See the
UNITS
BIAS
µMho
3
3437f
A/V
kHz
kHz
V/V
mA
mA
mA
mV
mA
mV
mV
kΩ
µA
nA
µA
µA
µA
%
is
V
V
V
V