Datasheet

4
LTC4006
4006fa
The ● denotes specifications which apply over the full operating
temperature range (Note 4), otherwise specifications are at T
A
= 25°C. V
DCIN
= 20V, V
BAT
= 12V unless otherwise noted.
ELECTRICAL CHARACTERISTICS
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
Oscillator
f
OSC
Regulator Switching Frequency 255 300 345 kHz
f
MIN
Regulator Switching Frequency in Drop Out Duty Cycle ≥ 98% 20 25 kHz
DC
MAX
Regulator Maximum Duty Cycle V
CSP
= V
BAT
98 99 %
Gate Drivers (TGATE, BGATE)
V
TGATE
High (V
CLN
– V
TGATE
)I
TGATE
= –1mA 50 mV
V
BGATE
High C
LOAD
= 3000pF 4.5 5.6 10 V
V
TGATE
Low (V
CLN
– V
TGATE
)C
LOAD
= 3000pF 4.5 5.6 10 V
V
BGATE
Low I
BGATE
= 1mA 50 mV
TGATE Transition Time
TGTR TGATE Rise Time C
LOAD
= 3000pF, 10% to 90% 50 110 ns
TGTF TGATE Fall Time C
LOAD
= 3000pF, 10% to 90% 50 100 ns
BGATE Transition Time
BGTR BGATE Rise Time C
LOAD
= 3000pF, 10% to 90% 40 90 ns
BGTF BGATE Fall Time C
LOAD
= 3000pF, 10% to 90% 40 80 ns
V
TGATE
at Shutdown (V
CLN
– V
TGATE
)I
TGATE
= –1µA, DCIN = 0V, CLN = 12V 100 mV
V
BGATE
at Shutdown I
BGATE
= 1µA, DCIN = 0V, CLN = 12V 100 mV
Note 1: Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2: See Test Circuit
Note 3: Does not include tolerance of current sense resistor.
Note 4: The LTC4006E 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.
TYPICAL PERFOR A CE CHARACTERISTICS
UW
INFET Response Time to
Reverse Current
TEST PERFORMED ON DEMOBOARD
V
IN
= 15VDC
CHARGER = ON
I
CHARGE
= <10mA
V
s
OF PFET (5V/DIV)
I
d
(REVERSE) OF
PFET (5A/DIV)
V
gs
OF PFET (2V/DIV)
4006 G01
LTC4006-2
INFET = 1/2 Si4925DY
V
gs
= 0
V
s
= 0V
I
d
= 0A
1.25µs/DIV
V
OUT
vs I
OUT
PWM Frequency vs Duty Cycle
DUTY CYCLE (V
OUT
/V
IN
)
0 0.1 0.2 0.4 0.6 0.90.80.3 0.5 0.7 1.0
PWM FREQUENCY (kHz)
4006 G03
PROGRAMMED CURRENT = 10%
DCIN = 15V
DCIN = 20V
DCIN = 24V
350
300
250
200
150
100
50
0
OUTPUT CURRENT (A)
0 0.5 1.0 2.0 3.0 4.01.5 2.5 3.5 4.5
OUTPUT VOLTAGE ERROR (%)
4006 G02
DCIN = 20V
V
BAT
= 12.6V
0
–0.5
–1.0
–1.5
–2.0
–2.5
–3.0
–3.5
–4.0
–4.5
–5.0