LT1684
ELECTRICAL CHARACTERISTICS
The q denotes the specifications which apply over the full operating temperature range,
V + – V – = 20V, Voltages referenced to pin OUT, VOUT = VATREF unless otherwise noted.
otherwise
specifications
are
at
TA
=
25°C.
SYMBOL PARAMETER
CONDITIONS
MIN TYP MAX UNITS
Supply and Protection
IS
DC Supply Current (Note 2)
|V +|
Local Supply Voltages
|V –|
VGATE+
Active Tracking Supply FET
Bias Voltage
VGATE –
Active Tracking Supply FET
Bias Voltage
PWM Receiver
IN A – IN B ≥ 1.6V
VGATE+ ≥ V +
VGATE– ≤ V –
IGATE+ = –100µA,
ATREF = 0V
IGATE– = 100µA,
ATREF = 0V
q
680 950
µA
q 6.5
10
V
q 13.2 14.0 14.8
V
q –14.8 –14.0 –13.2
V
fPWM
Input Carrier Frequency
10
kHz
VIN
Minimum Valid Differential Input
Differential Input Threshold
| IN A – IN B |
IN A – IN B or IN B – IN A
q 1.6
V
q 0.50 0.70 1.00
V
RIN
Differential Input Overdrive Impedance VIN > VTH + 100mV
(Note 3, 5)
q7
10
kΩ
RINA,INB
Single-Ended Input Impedance
(Note 5)
To Pin OUT
q 50
kΩ
BG Buffer
VBGOUT BGOUT Normalized Voltage
Magnitude |VBGOUT|
1.235 1.250 1.265
V
q 1.225 1.250 1.275
V
VBGOUTOS
IBGOUTSC
Output Offset Voltage
[(VBGOUT+) + (VBGOUT–)]/2
BGOUT Short-Circuit Current
–7
q –10
7
mV
10
mV
q ±2
±4.5
mA
RBGOUT
tr
tf
BGOUT Output Impedance
BGOUT Rise Time (10% to 90%)
BGOUT Fall Time (10% to 90%)
– 2mA ≤ IBGOUT ≤ 2mA
ROUT = 5k, COUT = 10pF
ROUT = 5k, COUT = 10pF
0.2
Ω
q
160 300
ns
q
260 400
ns
∆tr-f
BGOUT RiseTime – Fall Time
tpr
BGOUT Propagation Delay PWM Input ROUT = 5k, COUT = 10pF
Transition to 10% Output (Rising Edge)
q – 200 –100
0
ns
q
340 500
ns
tpf
BGOUT Propagation Delay PWM Input ROUT = 5k, COUT = 10pF
Transition to 90% Output (Falling Edge)
q
440 600
ns
∆tp
BGOUT Propagation Delay
Rising Edge – Falling Edge
q – 200 –100 100
ns
Output Amplifier
VOUTOS
ROUT
IOUTSC
OUT Offset Voltage
OUT Output Impedance
OUT Short-Circuit Current
VAMPIN = 0v, IOUT = 0A
RAMPIN = 10k (Note 4)
–6
q –8
6
mV
8
mV
–10mA ≥ ILIM+ ≥ –100mA, LIM + Shorted to OUT
10mA ≤ IOUT ≤ 100mA, LIM – Shorted to V –
0.01
Ω
0.15
Ω
LIM + Shorted to OUT
LIM – Shorted to V –
q ±100 ±190
mA
Note 1: Absolute Maximum Ratings are those values beyond which the life
of the device may be impaired.
Note 2: IC Supply current specification represents unloaded condition and
does not include external FET gate pull up/down currents (GATE +, GATE –
pins). Actual total IC bias currents will be higher and vary with operating
conditions. See Applications Information.
Note 3: PWM inputs are high impedance through ±100mV beyond the
input thresholds.
Note 4: 10k resistor from pin AMPIN to ground.
Note 5: Guaranteed but not tested.
3