Datasheet

LT1683
3
1683fd
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
I
ESK
Error Amp Sink Current V
FB
= V
REF
+ 150mV, V
C
= 0.9V
l
120 200 350 µA
I
ESRC
Error Amp Source Current V
FB
= V
REF
– 150mV, V
C
= 0.9V
l
120 200 350 µA
V
CLH
Error Amp Clamp Voltage High Clamp, V
FB
= 1V 1.27 V
V
CLL
Error Amp Clamp Voltage Low Clamp, V
FB
= 1.5V 0.12 V
A
V
Error Amplifier Voltage Gain 180 250 V/V
FB
OV
FB Overvoltage Shutdown Outputs Drivers Disabled 1.47 V
I
SS
Soft-Start Charge Current V
SS
= 1V 9.0 12 µA
Oscillator and Sync
f
MAX
Max Switch Frequency 250 kHz
f
SYNC
Synchronization Frequency Range Oscillator Frequency = 250kHz 290 kHz
V
SYNC
SYNC Pin Input Threshold
l
0.7 1.4 2.0
R
SYNC
SYNC Pin Input Resistance 40 kΩ
Gate Drives (Specifications Apply to Either A or B Unless Otherwise Noted)
DC
MAX
Maximum Switch Duty Cycle R
VSL
= R
CSL
= 4.85k,
Osc Frequency = 25kHz
l
45 46 %
VG
ON
Gate On Voltage V
IN
= 12, GCL = 12
V
IN
= 12, GCL = 8
10
7.6
10.4
7.9
10.7
8.1
V
V
VG
OFF
Gate Off Voltage V
IN
= 12V 0.2 0.35 V
IG
SO
Max Gate Source Current V
IN
= 12V 0.3 A
IG
SK
Max Gate Sink Current V
IN
= 12V 0.3 A
V
INUVLO
Gate Drive Undervoltage Lockout (Note 5) V
GCL
= 6.5V, Gates Enabled 7.3 7.5 V
Current Sense
t
IBL
Switch Current Limit Blanking Time 100 ns
V
SENSE
Sense Voltage Shutdown Voltage V
C
Pulled Low
l
86 103 120 mV
V
SENSEF
Sense Voltage Fault Threshold
l
230 300 mV
Slew Control (for the Following Slew Tests See Test Circuit in Figure 1b)
V
SLEWR
Output Voltage Slew Rising Edge R
VSL
= R
CSL
= 17k 26 V/µs
V
SLEWF
Output Voltage Slew Falling Edge R
VSL
= R
CSL
= 17k 19 V/µs
VI
SLEWR
Output Current Slew Rising Edge (CS Pin Voltage) R
VSL
= R
CSL
= 17k 0.21 V/µs
VI
SLEWF
Output Current Slew Falling Edge (CS Pin Voltage) R
VSL
= R
CSL
= 17k 0.21 V/µs
Supply and Protection
V
INMIN
Minimum Input Voltage (Note 4) V
GCL
= V
IN
l
2.55 3.6 V
I
VIN
Supply Current (Note 2) R
VSL
= R
CSL
= 17k, V
IN
= 12
R
VSL
= R
CSL
= 17k, V
IN
= 20
l
l
25
35
45
55
mA
mA
V
SHDN
Shutdown Turn-On Threshold
l
1.31 1.39 1.48 V
∆V
SHDN
Shutdown Turn-On Voltage Hysteresis
l
50 110 180 mV
I
SHDN
Shutdown Input Current Hysteresis
l
10 24 35 µA
V5 5V Reference Voltage 6.5V ≤ V
IN
≤ 20V, IV5 = 5mA
6.5V ≤ V
IN
≤ 20V, IV5 = –5mA
4.85
4.80
5
5
5.20
5.15
V
V
IV5
SC
5V Reference Short-Circuit Current V
IN
= 6.5V Source
V
IN
= 6.5V Sink
10
–10
mA
mA
ELECTRICAL CHARACTERISTICS
The ● denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
IN
= 12V, V
C
= 0.9V, V
FB
= V
REF
, R
VSL
, R
CSL
= 16.9k, R
T
= 16.9k and
other pins open unless otherwise noted.