Datasheet

3
LT1769
1769fa
ELECTRICAL CHARACTERISTICS
The ● denotes specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
CC
= 16V, V
BAT
= 8V, R
S2
= R
S3
= 200Ω (see Block Diagram),
V
CLN
= V
CC
. No load on any outputs unless otherwise noted.
PARAMETER CONDITIONS MIN TYP MAX UNITS
Overall
V
CC
Undervoltage Lockout (Switch OFF) Threshold Measured at UV Pin ● 678 V
UV Pin Input Current 0.2V ≤ V
UV
≤ 8V ● 0.1 5 µA
UV Output Voltage at UV
OUT
Pin In Undervoltage State, I
UVOUT
= 70µA ● 0.1 0.5 V
UV Output Leakage Current at UV
OUT
Pin 8V ≤ V
UV
, V
UVOUT
= 5V ● 0.1 3 µA
Reverse Current from Battery (When V
CC
Is V
BAT
≤ 20V, V
UV
≤ 0.4V 3 15 µA
Not Connected, V
SW
Is Floating)
Boost Pin Current V
CC
= 20V, V
BOOST
= 0V 0.1 10 µA
V
CC
= 28V, V
BOOST
= 0V 0.25 20 µA
2V ≤ V
BOOST
– V
CC
< 8V (Switch ON) 6 9 mA
8V ≤ V
BOOST
– V
CC
≤ 25V (Switch ON) 8 12 mA
Switch
Switch ON Resistance 8V ≤ V
CC
≤ V
MAX
, I
SW
= 2A,
V
BOOST
– V
SW
≥ 2V ● 0.15 0.25 Ω
∆I
BOOST
/∆I
SW
During Switch ON V
BOOST
= 24V, I
SW
≤ 2A 25 35 mA/A
Switch OFF Leakage Current V
SW
= 0V, V
CC
≤ 20V ● 2 100 µA
20V < V
CC
≤ 28V ● 4 200 µA
Minimum I
PROG
for Switch ON 2420 µA
Minimum I
PROG
for Switch OFF ● 1 2.4 mA
Maximum V
BAT
for Switch ON ● V
CC
– 2 V
Current Sense Amplifier CA1 Inputs (Sense, BAT)
Input Bias Current ● –50 –125 µA
Input Common Mode Low ● –0.25 V
Input Common Mode High ● V
CC
– 2 V
SPIN Input Current –100 –200 µA
Reference
Reference Voltage (Note 3) R
PROG
= 4.93k, Measured at OVP with
VA Supplying I
PROG
and Switch OFF 2.448 2.465 2.477 V
Reference Voltage All Conditions of V
CC
,T
A
≥ 0°C ● 2.441 2.489 V
T
A
< 0°C (Note 4) ● 2.43 2.489 V
Oscillator
Switching Frequency 180 200 220 kHz
Switching Frequency All Conditions of V
CC
,T
A
≥ 0°C ● 170 200 230 kHz
T
A
< 0°C ● 160 230 kHz
Maximum Duty Cycle 90 93 %
● 85 %
Current Amplifier CA2
Transconductance V
C
= 1V, I
VC
= ±1µA 150 250 550 µmho
Maximum V
C
for Switch OFF ● 0.6 V
I
VC
Current (Out of Pin) V
C
≥ 0.6V 100 µA
V
C
< 0.45V 3 mA