ltc4268cdkd-1-trpbf Linear Technology Corporation, ltc4268cdkd-1-trpbf Datasheet - Page 4

• Manufacturer Part Number: ltc4268cdkd-1-trpbf
• Description: High Power Pd With Synchronous Noopto Flyback Controller
• Manufacturer: Linear Technology Corporation

LTC4268-1
ELECTRICAL CHARACTERISTICS
SYMBOL
R
V
V
I
I
ΔI
R
R
V
I
V
V
I
R
I
I
I
I
f
C
t
t
t
DC
V
R
temperature range, otherwise specifi cations are at T
R
4
VPORTN
IN_CLASS
PWRGD_LEAK
PWRGD_LEAK
OUT_LEAK
LIM_HI
LIM_LO
LIM_DISA
OSC
ON(MIN)
ENDLY
PGDLY
IH_ILIM
IL_ILIM
PWRGD_OUT
PWRGD_OUT
PWRGD_VCLAMP
OSC
SYNC
INPUT_SHDN
SIGNATURE
INVALID
ON
SYNC
PGDLY
CLASS
ON(MAX)
= 27.4k, R
ENDLY
PARAMETER
Shutdown Input Resistance
I
I
V
IC Supply Current During Classifi cation
Current Accuracy During Classifi cation
Signature Resistance
Invalid Signature Resistance
Active Low Power Good Output Voltage
Active Low Power Good Output Leakage V
Active High Power Good Output Voltage I = 0.5mA, V
Active High Power Good Voltage
Limiting Clamp
Active High Power Good Output Leakage V
On-Resistance
V
Input Current Limit, High Level
Input Current Limit, Low Level
Safeguard Current Limit When I
Disabled
Oscillator Frequency
Oscillator Capacitor Value
Minimum Switch on Time
Flyback Enable Delay Time
PG Turn-On Delay Time
Maximum Switch Duty Cycle
SYNC Pin Threshold
SYNC Pin Input Resistance
LIM_EN
LIM_EN
PORTN
OUT
= 90k, unless otherwise specifi ed.
Leakage
High Level Input Voltage
Low Level Input Voltage
Supply Current
LIM
is
A
= 25°C. V
CONDITIONS
With Respect to V
With Respect to V
High Level Enables Current Limit
With Respect to V
V
V
(Note 14)
10mA < I
–12.5V ≤ V
–1.5V ≤ V
to V
Measurement (Notes 8, 9)
–1.5V ≤ V
to V
Measurement (Notes 8, 9)
I = 1mA, V
Referenced to V
PWRGD Referenced to V
I = 2mA, V
V
V
I = 700mA, V
V
V
0V (Note 15)
V
Floating (Notes 18, 19)
V
(Notes 18, 19)
V
V
(Notes 18, 19, 20)
C
(Note 21)
PORTN
PORTN
PORT
NEG
PWRGD
NEG
PORTN
PORTN
PORTN
PORTN
PORTN
NEG
OSC
The
PORTN
PORTP
(Note 3)
= V
= –52.5V I
= 100pF
= 0V, V
= –54V
= –17.5V, V
to V
= –57V, V
= –54V, V
= –54V, V
= –54V,
= 11V with Respect to V
l
PORTN
CC
CLASS
, IEEE 802.3af Two-Point
, IEEE 802.3af Two-Point
PORTN
PORTN
PORTN
NEG
denotes the specifi cations which apply over the full operating
PORTN
NEG
= 14V, SG open, V
PORTN
PORTN
PWRGD
= 0V, PWRGD Referenced to
< 75mA
= –54V
PORTN
(Note 16)
LIM_EN
≤ –10.1V, SHDN Tied
≤ –10.1V, SHDN Tied
= –54V, PWRGD
PORTP
NEG
NEG
≤ –21V (Notes 15, 16)
PORTN
PORTN
PORTN
= –52V, V
NEG
= –48V, Measured from
= 57V
= –53V I
= –53V
Tied To V
Tied to V
= SHDN = V
(Note 13)
(Note 13)
NEG
NEG
(Note 17)
LIM_EN
PORTP
PORTN
= –4V
NEG
CMP
NEG
,
= 1.5V, V
=
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
SENSE
23.25
MIN
0.55
100
700
250
1.2
12
84
33
85
4
= 0V, R
CMP
0.62
1.45
1.53
TYP
750
300
100
200
265
200
0.5
10
14
88
40
= 1k, R
MAX
0.70
±3.5
11.8
0.35
16.5
1.65
800
350
110
200
0.5
0.6
0.8
2.1
26
1
3
1
1
1
tON
= 90k,
UNITS
42681fa
kHz
mA
mA
mA
mA
kΩ
kΩ
kΩ
kΩ
μA
μA
μA
pF
ns
ns
ns
%
%
Ω
Ω
V
V
V
V
V
A
V