Datasheet
2
LTC3776
3776fa
Input Supply Voltage (V
IN
) ........................ –0.3V to 10V
PLLLPF, RUN/SS, SYNC/SSEN,
V
REF
, SENSE1
+
, SENSE2
+
, V
FB2
IPRG1, IPRG2 Voltages ................. –0.3V to (V
IN
+ 0.3V)
V
FB1
, I
TH1
, I
TH2
Voltages ........................... –0.3V to 2.4V
SW1, SW2 Voltages .............. –2V to V
IN
+ 1V (10V Max)
PGOOD ..................................................... –0.3V to 10V
ABSOLUTE AXI U RATI GS
WWWU
(Note 1)
TG1, TG2, BG1, BG2 Peak Output Current (<10μs) ..... 1A
Operating Temperature Range (Note 2) ... –40°C to 85°C
Storage Temperature Range .................. –65°C to 125°C
Junction Temperature (Note 3) ............................ 125°C
Lead Temperature (Soldering, 10 sec)
(LTC3776EGN) ..................................................... 300°C
PACKAGE/ORDER I FOR ATIO
UU
W
24 23 22 21 20 19
7 8 9
TOP VIEW
25
UF PACKAGE
24-LEAD (4mm × 4mm) PLASTIC QFN
10 11 12
6
5
4
3
2
1
13
14
15
16
17
18
I
TH1
IPRG2
PLLLPF
SGND
V
IN
V
REF
SYNC/SSEN
TG1
PGND
TG2
RUN/SS
BG2
V
FB1
IPRG1
SW1
SENSE1
+
PGND
BG1
V
FB2
I
TH2
PGOOD
SW2
SENSE2
+
PGND
T
JMAX
= 125°C, θ
JA
= 37°C/W
EXPOSED PAD (PIN 25) IS PGND
MUST BE SOLDERED TO PCB
1
2
3
4
5
6
7
8
9
10
11
12
TOP VIEW
GN PACKAGE
24-LEAD PLASTIC SSOP
24
23
22
21
20
19
18
17
16
15
14
13
SW1
IPRG1
V
FB1
I
TH1
IPRG2
PLLLPF
SGND
V
IN
V
REF
V
FB2
I
TH2
PGOOD
SENSE1
+
PGND
BG1
SYNC/SSEN
TG1
PGND
TG2
RUN/SS
BG2
PGND
SENSE2
+
SW2
ORDER PART
NUMBER
UF PART MARKING
3776
LTC3776EUF
T
JMAX
= 125°C, θ
JA
= 130°C/ W
ORDER PART
NUMBER
LTC3776EGN
Consult LTC Marketing for parts specified with wider operating temperature ranges.
ELECTRICAL CHARACTERISTICS
The ● denotes specifications that apply over the full operating temperature
range, otherwise specifications are at T
A
= 25°C. V
IN
= 4.2V unless otherwise specified.
PARAMETER CONDITIONS MIN TYP MAX UNITS
Main Control Loops
Input DC Supply Current (Note 4)
Normal Operation I
TH1
= I
TH2
= 1.3V 575 850 μA
Shutdown RUN/SS = 0V 9 20 μA
UVLO V
IN
< UVLO Threshold –200mV 3 10 μA
Undervoltage Lockout Threshold V
IN
Falling ● 1.95 2.25 2.55 V
V
IN
Rising ● 2.15 2.45 2.75 V
Shutdown Threshold at RUN/SS 0.45 0.65 0.85 V
Start-Up Current Source RUN/SS = 0V 0.4 0.7 1 μA
Regulated Feedback Voltage (V
FB1
)0°C to 85°C (Note 5) 0.591 0.6 0.609 V
–40°C to 85°C
● 0.588 0.6 0.612 V
Regulated Feedback Voltage (V
FB2
)V
REF
= 2.5V ● 1.232 1.250 1.268 V
Output Voltage Line Regulation (V
FB1
) 2.75V < V
IN
< 9.8V (Note 5) 0.05 0.2 mV/V
Output Voltage Line Regulation (V
FB2
) 0.02 0.1 mV/V