2
LTC1643AL
LTC1643AL-1/LTC1643AH
1643afb
GN PART MARKING
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
I
DD
V
12VIN
Supply Current ON = GND, ON = 3V ● 3.5 8 mA
V
LKO
Undervoltage Lockout 12V
IN
● 7 9.5 10.8 V
3V
IN
● 2.25 2.5 2.75 V
5V
IN
● 2.25 2.5 2.75 V
V
FB
Foldback Current Limit Voltage V
FB
= (V
5VIN
– V
5VSENSE
), V
5VOUT
= 0V ● 4 7.5 12 mV
V
FB
= (V
5VIN
– V
5VSENSE
), V
5VOUT
> 4V ● 40 53 65 mV
V
FB
= (V
3VIN
– V
3VSENSE
), V
3VOUT
= 0V ● 4 7.5 12 mV
V
FB
= (V
3VIN
– V
3VSENSE
), V
3VOUT
> 2V ● 40 53 65 mV
t
CB
Circuit Breaker Trip Filter Time 14.6 µs
I
CP
GATE Pin Output Current Charge Pump On, V
GATE
= GND, FAULT = High ● – 20 – 62 –100 µA
Charge Pump Off, V
GATE
= 5V, FAULT = High 200 µA
Charge Pump Off, V
GATE
= 2V, FAULT = Low ● 3 17.5 mA
∆V
GATE
External Gate Voltage (V
12VIN
– V
GATE
) 100 200 mV
V
DROP
Internal Switch Voltage Drop (V
12VIN
– V
12VOUT
), 0°C ≤ T
A
≤ 70°C ● 225 600
I
12VOUT
= 500mA –40°C ≤ T
A
≤ 85°C ● 225 750 mV
(V
EEOUT
– V
EEIN
), I
VEEIN
= 100mA ● 125 250 mV
I
CL
Current Foldback 12V
IN
= 12V, 12V
OUT
= 0V ● 50 250 600 mA
12V
IN
= 12V, 12V
OUT
= 10V ● 525 850 1500 mA
V
EEIN
= –12V, V
EEOUT
= 0V (LTC1643AL/LTC1643AH Only) ● 50 160 500 mA
V
EEIN
= –12V, V
EEOUT
= –10V ● 225 450 800 mA
T
TS
Thermal Shutdown Temperature 150 °C
V
TH
Power-Good Threshold Voltage V
12VOUT
0°C ≤ T
A
≤ 70°C ● 10.8 11.1 11.4 V
LTC1643AH/LTC1643AL Only –40°C ≤ T
A
≤ 85°C ● 10.4 11.1 11.4 V
V
EEOUT
0°C ≤ T
A
≤ 70°C ● – 10.2 – 10.5 – 10.8 V
LTC1643AH/LTC1643AL Only –40°C ≤ T
A
≤ 85°C ● – 10.0 – 10.5 – 10.8 V
ABSOLUTE MAXIMUM RATINGS
W
WW
U
PACKAGE/ORDER INFORMATION
W
U
U
ORDER PART NUMBER
(Note 1)
Supply Voltages
12V
IN
................................................................ 13.2V
V
EEIN
.............................................................. –13.2V
Input Voltage (Pin 5) ................ –0.3V
to (12V
IN
+ 0.3V)
Output Voltages (Pins 6, 7) ...... –0.3V
to (12V
IN
+ 0.3V)
Analog Voltages
(Pins 3, 4, 9, 10 to 14) ........ –0.3V
to (12V
IN
+ 0.3V)
V
EEOUT
............................................ –13.2V to + 0.3V
12V
OUT
.............................................. – 0.3V to 13.2V
Operating Temperature Range
LTC1643ALC/LTC1643AL-1C/
LTC1643AHC ........................................... 0°C to 70°C
LTC1643ALI/LTC1643AL-1I/
LTC1643AHI ...................................... – 40°C to 85°C
Storage Temperature Range ................. –65°C to 150°C
Lead Temperature (Soldering, 10 sec).................. 300°C
TOP VIEW
GN PACKAGE
16-LEAD NARROW PLASTIC SSOP
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
12V
IN
V
EEIN
3V
OUT
TIMER
ON/ON*
FAULT
PWRGD
GND
12V
OUT
V
EEOUT
5V
OUT
5V
IN
5V
SENSE
GATE
3V
SENSE
3V
IN
*ON FOR LTC1643AH,
ON FOR LTC1643AL/LTC1643AL-1
T
JMAX
= 150°C, θ
JA
= 135°C/ W
LTC1643AHCGN
LTC1643ALCGN
LTC1643AL-1CGN
LTC1643AHIGN
LTC1643ALIGN
LTC1643AL-1IGN
DC ELECTRICAL CHARACTERISTICS
The ● denotes specifications which apply over the full operating
temperature range, otherwise specifications are T
A
= 25°C. V
12VIN
= 12V, V
EEIN
= –12V, V
3VIN
= 3.3V, V
5VIN
= 5V (Note 2)
1643AH
1643AL
643AL1
643AHI
643ALI
43AL1I
Consult LTC Marketing for parts specified with wider operating temperature ranges.
Order Options Tape and Reel: Add #TR
Lead Free: Add #PBF Lead Free Tape and Reel: Add #TRPB
Lead Free Part Marking: http://www.linear.com/leadfree/
