4
LTC1436A
LTC1436-PLL-A/LTC1437A
14367afb
ELECTRICAL CHARACTERISTICS
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
Low-Battery Comparator
V
SATLBO
LBO Saturation Voltage I
LBO
= 1.6mA, V
LBI
= 1.1V 0.6 1 V
I
LLBO
LBO Leakage V
LBO
= 12V, V
LBI
= 1.4V ● 0.01 1 µA
V
THLBI
LBI Trip Voltage High to Low Transition on LBO ● 1.16 1.19 1.22 V
I
INLBI
LBI Input Current V
LBI
= 1.19V ● 150 nA
V
HYSLBO
LBO Hysteresis 20 mV
Auxiliary Regulator/Comparator
I
AUXDR
AUXDR Current V
EXTVCC
= 0V
Max Current Sinking Capability V
AUXDR
= 4V, V
AUXFB
= 1.0V, V
AUXON
= 5V 10 15 mA
Control Current V
AUXDR
= 5V, V
AUXFB
= 1.5V, V
AUXON
= 5V 1 5 µA
Leakage When Off V
AUXDR
= 24V, V
AUXFB
= 1.5V, V
AUXON
= 0V 0.01 1 µA
I
IN
AUXFB
AUXFB Input Current V
AUXFB
= 1.19V, V
AUXON
= 5V 0.01 1 µA
I
IN AUXON
AUXON Input Current V
AUXON
= 5V 0.01 1 µA
V
TH AUXON
AUXON Trip Voltage V
AUXDR
= 4V, V
AUXFB
= 1.0V 1.0 1.19 1.4 V
V
SAT AUXDR
AUXDR Saturation Voltage I
AUXDR
= 1.6mA, V
AUXFB
= 1.0V, V
AUXON
= 5V 0.4 0.8 V
V
AUXFB
AUXFB Voltage V
AUXON
= 5V, 11V < V
AUXDR
< 24V (Note 5) ● 11.5 12 12.5 V
V
AUXON
= 5V, 3V < V
AUXDR
< 7V (Note 5) ● 1.14 1.19 1.24 V
V
TH AUXDR
AUXFB Divider Disconnect Voltage V
AUXON
= 5V (Note 6), Ramping Negative 7.5 8.5 9.5 V
f
OSC
(kHz) =
+
–1
8.4(10
8
)
C
OSC
(pF) + 11
()
1
I
CHG
()
1
I
DIS
Note 6: The Auxiliary Regulator is tested in a feedback loop which servos
V
AUXFB
to the balance point for the error amplifier. For applications with
V
AUXDR
> 9.5V, V
AUXFB
uses an internal resistive divider. See
Applications Information.
Note 7: The minimum on-time test condition corresponds to an inductor
peak-to-peak ripple current ≥ 40% of I
MAX
(see Minimum On-Time
Considerations in the Applications Information section).
Note 8: The LTC1436AE is guaranteed to meet performance
specifications from 0°C to 70°C. Specifications over the –40°C to 85°C
operating temperature range are assured by design, characterization and
correlation with statistical process controls.
Note 1: Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.
Note 2: T
J
is calculated from the ambient temperature T
A
and power
dissipation P
D
according to the following formulas:
LTC1436ACGN/LTC1436ACGN-PLL/LTC1436AEGN/LTC1436AIGN/
LTC1436AIGN-PLL: T
J
= T
A
+ (P
D
)(110 °C/W)
LTC1437ACG/LTC1437AIG: T
J
= T
A
+ (P
D
)(95 °C/W)
Note 3: The LTC1436A/LTC1437A are tested in a feedback loop which
servos V
OSENSE
to the balance point for the error amplifier
(V
ITH
= 1.19V).
Note 4: Dynamic supply current is higher due to the gate charge being
delivered at the switching frequency. See Applications Information
section.
Note 5: Oscillator frequency is tested by measuring the C
OSC
charge and
discharge currents and applying the formula:
The ● denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
IN
= 15V, V
RUN/SS
= 5V unless otherwise noted.