MAX1858AEEG+T
Analog Devices Inc./Maxim Integrated
IC REG CTRLR BUCK 24QSOP
Na stanie9024 pcs
Current Limit, Enable, Frequency Control, Reset
2
-
Yes
Yes
-
Buck
MAX1858
Tape & Reel (TR)
Transistor Driver
-
-40°C ~ 85°C (TA)
Surface Mount
24-SSOP (0.154', 3.90mm Width)
24-QSOP
Step-Down
100kHz ~ 600kHz
2
Positive
4.5V ~ 23V
RFQ
UCC39421PWTR
Texas Instruments
IC REG CTRLR MULT TOP 16TSSOP
Na stanie6050 pcs
Enable, Frequency Control, Low Battery, Reset
1
88%
Yes
Yes
-
Boost, Flyback, SEPIC
UCC39421
Tape & Reel (TR)
Transistor Driver
-
0°C ~ 70°C (TA)
Surface Mount
16-TSSOP (0.173", 4.40mm Width)
16-TSSOP
Step-Up, Step-Up/Step-Down
150kHz ~ 1.2MHz
1
Positive
1.8V ~ 8V
RFQ
UCC28084DR
Texas Instruments
IC REG CTRLR MULT TOPOLOGY 8SOIC
Na stanie17622 pcs
Current Limit, Frequency Control
1
49%
Yes
No
-
Half-Bridge, Push-Pull
UCC28084
Tape & Reel (TR)
Transistor Driver
-
-40°C ~ 85°C (TA)
Surface Mount
8-SOIC (0.154', 3.90mm Width)
8-SOIC
Step-Up/Step-Down
200kHz
2
Positive
4.1V ~ 15V
RFQ
UCC2813N-1
Texas Instruments
IC REG CTRLR MULT TOPOLOGY 8DIP
Na stanie5130 pcs
Frequency Control
1
49%
No
No
-
Boost, Flyback, Forward Converter
UCC2813
Tube
Transistor Driver
-
-40°C ~ 85°C (TA)
Through Hole
8-DIP (0.300', 7.62mm)
8-PDIP
Step-Up, Step-Up/Step-Down
-
1
Positive
7.4V ~ 12V
RFQ
TPS51120RHBR
Texas Instruments
IC REG CTRLR BUCK 32QFN
Na stanie13277 pcs
Enable, On Time Control, Power Good
1
-
Yes
No
-
Buck
TPS51120
Tape & Reel (TR)
Transistor Driver
D-CAP™
-40°C ~ 85°C (TA)
Surface Mount
32-VFQFN Exposed Pad
32-VQFN (5x5)
Step-Down
-
2
Positive
4.5V ~ 28V
RFQ
ISL6741IB
Renesas Electronics America Inc
IC REG CTRLR MULT TOP 16SOIC
Na stanie7460 pcs
Enable, Frequency Control, Soft Start
1
83%
Yes
Yes
-
Full-Bridge, Half-Bridge, Push-Pull
ISL6741
Tube
Transistor Driver
-
-40°C ~ 105°C (TA)
Surface Mount
16-SOIC (0.154', 3.90mm Width)
16-SOIC
Step-Up/Step-Down
Up to 1MHz
2
Positive, Isolation Capable
9V ~ 16V
RFQ
UC3844ADTR
Texas Instruments
IC REG CTRLR PWM CM 14SOIC
Na stanie74580 pcs
Frequency Control
1
48%
No
No
-
Boost, Buck, Flyback, Forward
UC3844
Tape & Reel (TR)
Transistor Driver
-
0°C ~ 70°C (TA)
Surface Mount
14-SOIC (0.154", 3.90mm Width)
14-SOIC
Step-Up, Step-Down, Step-Up/Step-Down
Up to 500kHz
1
Positive, Isolation Capable
10V ~ 30V
RFQ
LM5032MTC
Texas Instruments
IC REG CTRLR FWRD CONV 16TSSOP
Na stanie8920 pcs
Frequency Control, Soft Start
2
76%
No
Yes
-
Forward Converter
LM5032
Tube
Transistor Driver
-
-40°C ~ 125°C (TJ)
Surface Mount
16-TSSOP (0.173", 4.40mm Width)
16-TSSOP
Step-Up/Step-Down
200kHz, 600kHz
2
Positive
13V ~ 100V
RFQ
SC2545MLTRT
Semtech Corporation
IC REG CTRLR BUCK 24MLPQ
Na stanie11780 pcs
Current Limit, Enable, Frequency Control, Phase Control, Power Good, Soft Start
2
90%
Yes
No
-
Buck
SC2545
Tape & Reel (TR)
Transistor Driver
-
-40°C ~ 85°C (TA)
Surface Mount
24-VFQFN Exposed Pad
24-MLPQ (4x4)
Step-Down
100kHz ~ 300kHz
2
Positive
4.5V ~ 28V
RFQ
S-8521E33MC-BLST2G
ABLIC Inc.
IC REG CTRLR BUCK SOT23-5
Na stanie76250 pcs
Enable
1
100%
No
No
-
Buck
S-8521
Tape & Reel (TR)
Transistor Driver
-
-40°C ~ 85°C (TA)
Surface Mount
SC-74A, SOT-753
SOT-23-5
Step-Down
300kHz
1
Positive
2.5V ~ 10V
RFQ
UC3845BVNG
onsemi
IC REG CTRLR BOOST/FLYBACK 8DIP
Na stanie16050 pcs
Frequency Control
1
48%
No
No
-
Boost, Flyback
UC3845
Tube
Transistor Driver
-
-40°C ~ 105°C (TA)
Through Hole
8-DIP (0.300", 7.62mm)
8-PDIP
Step-Up, Step-Up/Step-Down
Up to 500kHz
1
Positive, Isolation Capable
7.6V ~ 30V
RFQ
LT1245CS8#TRPBF
Analog Devices Inc.
IC REG CTRLR BUCK 8SOIC
Na stanie8869 pcs
Frequency Control
1
48%
No
No
-
Buck
LT1245
Tape & Reel (TR)
Transistor Driver
-
0°C ~ 100°C (TJ)
Surface Mount
8-SOIC (0.154', 3.90mm Width)
8-SO
Step-Down
500kHz
1
Positive, Isolation Capable
8.2V ~ 25V
RFQ
MAX1987ETM+T
Analog Devices Inc./Maxim Integrated
INTEL IMVP4 DUAL-PHASE PWM CONTR
Na stanie7790 pcs
Current Limit, Enable, On Time Control, Power Good, Pulse Skipping, Saturation
2
100%
Yes
Yes
-
Buck
MAX1987
Tape & Reel (TR)
Transistor Driver
Quick-PWM™
-40°C ~ 85°C (TA)
Surface Mount
48-WFQFN Exposed Pad
48-TQFN (7x7)
Step-Down
200kHz, 300kHz, 550kHz
1
Positive
4.5V ~ 5.5V
RFQ
MAX797CSE
Analog Devices Inc./Maxim Integrated
IC REG CTRLR MULT TOP 16SOIC
Na stanie16200 pcs
Enable, Pulse Skipping, Soft Start
1
96%
Yes
Yes
-
Buck, Boost, Flyback
MAX797
Tube
Transistor Driver
-
0°C ~ 70°C (TA)
Surface Mount
16-SOIC (0.154', 3.90mm Width)
16-SOIC
Step-Up, Step-Up/Step-Down
150kHz, 300kHz
1
Positive
4.5V ~ 30V
RFQ
MAX8579EUB+
Analog Devices Inc./Maxim Integrated
IC REG CTRLR BUCK 10UMAX
Na stanie12976 pcs
Current Limit, Enable, Soft Start
1
-
Yes
No
-
Buck
MAX8579
Tube
Transistor Driver
-
-40°C ~ 85°C (TA)
Surface Mount
10-TFSOP, 10-MSOP (0.118', 3.00mm Width)
10-uMAX/uSOP
Step-Down
200kHz ~ 500kHz
1
Positive
3V ~ 28V
RFQ
LT1737IS#TRPBF
Analog Devices Inc.
IC REG CTRLR FLYBACK 16SOIC
Na stanie4587 pcs
Enable, Soft Start
1
90%
No
No
-
Flyback
LT1737
Tape & Reel (TR)
Transistor Driver
-
-40°C ~ 125°C (TJ)
Surface Mount
16-SOIC (0.154", 3.90mm Width)
16-SO
Step-Up/Step-Down
90kHz ~ 115kHz
1
Positive or Negative, Isolation Capable
4.1V ~ 20V
RFQ
SG3524P
STMicroelectronics
IC REG CTLR FLYBK/PSH-PLL 16SOIC
Na stanie31812 pcs
Enable
1
45%
No
No
-
Flyback, Push-Pull
SG3524
Tube
Transistor Driver
-
0°C ~ 70°C (TA)
Surface Mount
16-SOIC (0.154", 3.90mm Width)
16-SO
Step-Up/Step-Down
300kHz
2
Positive
8V ~ 40V
RFQ
TPS53676RSLR
Texas Instruments
TPS53676 - DUAL CHANNEL D-CAP CO
Na stanie15860 pcs
-
-
-
-
-
-
-
TPS53676
Bulk
-
*
-
-
-
-
-
-
-
-
-
RFQ
HIP6302CB
Intersil
MPU CORE VOLTAGE REGULATOR
Na stanie22908 pcs
Enable, Frequency Control, Power Good
2
-
-
No
-
Buck
HIP6302
Tube
PWM Signal
-
0°C ~ 70°C (TA)
Surface Mount
16-SOIC (0.154", 3.90mm Width)
16-SOIC
Step-Down
50kHz ~ 1.5MHz
2
Positive
4.75V ~ 5.25V
RFQ
MIC38C43ABMM
Microchip Technology
IC REG CTRLR MULT TOPOLOGY 8MSOP
Na stanie9910 pcs
Frequency Control
1
96%
Yes
No
-
Buck, Boost, Flyback, Forward Converter
MIC38C43
Bulk
Transistor Driver
-
-40°C ~ 85°C (TA)
Surface Mount
8-TSSOP, 8-MSOP (0.118', 3.00mm Width)
8-MSOP
Step-Up, Step-Down, Step-Up/Step-Down
500kHz
1
Positive, Isolation Capable
7.6V ~ 20V
RFQ
BD9536FV-E2
Rohm Semiconductor
IC REG CTRLR BUCK 28SSOP
Na stanie6150 pcs
Current Limit, Enable, Frequency Control
1
-
Yes
No
-
Buck
BD9536
Tape & Reel (TR)
Transistor Driver
-
-20°C ~ 100°C (TA)
Surface Mount
28-LSSOP (0.220', 5.60mm Width)
28-SSOP-B
Step-Down
200kHz ~ 600kHz
2
Positive
7.5V ~ 15V
RFQ
LTC1435CG#TRPBF
Analog Devices Inc.
IC REG CTRLR BUCK 16SSOP
Na stanie3597 pcs
Enable, Soft Start
1
99%
Yes
No
-
Buck
LTC1435
Tape & Reel (TR)
Transistor Driver
-
0°C ~ 70°C (TA)
Surface Mount
16-SSOP (0.209', 5.30mm Width)
16-SSOP
Step-Down
Up to 400kHz
1
Positive
3.5V ~ 30V
RFQ
UC2842AD
Microchip Technology
IC REG CTRLR PWM CM 14-SOIC
Na stanie7646 pcs
Frequency Control
1
96%
No
No
-
Boost, Buck, Flyback, Forward
UC2842
Tube
Transistor Driver
-
-40°C ~ 85°C (TA)
Surface Mount
14-SOIC (0.154', 3.90mm Width)
14-SOIC
Step-Up, Step-Down
Up to 500kHz
1
Positive, Isolation Capable
10V ~ 30V
RFQ
UC3843N
Fairchild Semiconductor
SWITCHING CONTROLLER
Na stanie57040 pcs
Frequency Control
1
97%
No
No
-
Boost, Buck, Buck-Boost, Flyback, Forward
UC3843
Tube
Transistor Driver
-
0°C ~ 70°C (TA)
Through Hole
8-DIP (0.300", 7.62mm)
8-DIP
Step-Up, Step-Down, Step-Up/Step-Down
Up to 500kHz
1
Positive, Isolation Capable
7.6V ~ 30V
RFQ
LM34936RHFR
Texas Instruments
.5-55VIN 4 SWITCH BUCK-BOOST CON
Na stanie9592 pcs
Current Limit, Enable, Frequency Control, Power Good, Soft Start
1
100%
Yes
Yes
-
Buck-Boost
LM34936
Tape & Reel (TR)
Transistor Driver
-
-40°C ~ 125°C (TJ)
Surface Mount
28-VFQFN Exposed Pad
28-VQFN (5x4)
Step-Up/Step-Down
100kHz ~ 600kHz
1
Positive
4.2V ~ 30V
RFQ
TL5001AIP
Texas Instruments
IC REG CTRLR BUCK/BST/FLYBK 8DIP
Na stanie29797 pcs
Dead Time Control, Frequency Control
1
100%
No
No
-
Buck, Boost, Flyback
TL5001
Tube
Transistor Driver
-
-40°C ~ 85°C (TA)
Through Hole
8-DIP (0.300", 7.62mm)
8-PDIP
Step-Up, Step-Down, Step-Up/Step-Down
20kHz ~ 500kHz
1
Positive
3.6V ~ 40V
RFQ
L5991AD
STMicroelectronics
IC REG CTRLR FLYBACK 16SO
Na stanie17010 pcs
Current Limit, Frequency Control, Soft Start
1
93%
Yes
No
-
Flyback
L5991
Tube
Transistor Driver
-
-40°C ~ 150°C (TJ)
Surface Mount
16-SOIC (0.154", 3.90mm Width)
16-SO
Step-Up/Step-Down
Up to 1MHz
1
Positive, Isolation Capable
7.6V ~ 20V
RFQ
S-8352C30UA-K6PT2G
ABLIC Inc.
IC REG CTRLR BOOST SOT89-3
Na stanie56280 pcs
-
1
75%
No
No
-
Boost
S-8352
Tape & Reel (TR)
Transistor Driver
-
-40°C ~ 85°C (TA)
Surface Mount
TO-243AA
SOT-89-3
Step-Up
100kHz
1
Positive
0.9V ~ 10V
RFQ
SG3524D
Microchip Technology
IC REG CTRLR MULT TOP 16SOIC
Na stanie84550 pcs
Current Limit, Frequency Control
1
45%
No
No
-
Buck, Boost, Flyback, Forward Converter, Full-Bridge, Half-Bridge, Push-Pull
SG3524
Tube
Transistor Driver
-
0°C ~ 70°C (TA)
Surface Mount
16-SOIC (0.154', 3.90mm Width)
16-SOIC
Step-Up, Step-Down, Step-Up/Step-Down
450kHz
2
Positive, Isolation Capable
8V ~ 40V
RFQ
UCC3807DTR-1
Texas Instruments
IC REG CTRLR MULT TOPOLOGY 8SOIC
Na stanie13280 pcs
-
1
78%
No
No
-
Buck, Boost, Flyback, Forward Converter, SEPIC
UCC3807
Tape & Reel (TR)
Transistor Driver
-
0°C ~ 70°C (TA)
Surface Mount
8-SOIC (0.154', 3.90mm Width)
8-SOIC
Step-Up, Step-Down, Step-Up/Step-Down
202kHz
1
Positive
6.9V ~ 13.5V
RFQ
IR3640MPBF
Infineon Technologies
IC REG CTRLR BUCK 20MLPQ
Na stanie4740 pcs
Current Limit, Enable, Frequency Control, Power Good, Sequencing, Soft Start
1
92%
Yes
Yes
-
Buck
IR3640
Tube
Transistor Driver
-
-40°C ~ 125°C (TJ)
Surface Mount
20-VFQFN Exposed Pad
20-MLPQ (3x4)
Step-Down
225kHz ~ 1.65MHz
1
Positive
4.5V ~ 5.5V
RFQ
LTC3835IUFD#PBF
Analog Devices Inc.
IC REG CTRLR BUCK 20QFN
Na stanie6003 pcs
Enable, Phase Control, Power Good, Soft Start, Tracking
1
99.4%
Yes
No
-
Buck
LTC3835
Tube
Transistor Driver
-
-40°C ~ 85°C (TA)
Surface Mount
20-WFQFN Exposed Pad
20-QFN (4x5)
Step-Down
250kHz ~ 530kHz
1
Positive
4V ~ 36V
RFQ
UCC25705DTR
Texas Instruments
IC REG CTRLR MULT TOPOLOGY 8SOIC
Na stanie23589 pcs
Current Limit
1
93%
No
No
-
Boost, Flyback, Forward Converter
UCC25705
Tape & Reel (TR)
Transistor Driver
-
-40°C ~ 85°C (TA)
Surface Mount
8-SOIC (0.154", 3.90mm Width)
8-SOIC
Step-Up, Step-Up/Step-Down
1MHz
1
Positive, Isolation Capable
8.2V ~ 15V
RFQ
UC2524AN
Texas Instruments
IC REG CTRLR MULT TOPOLOGY 16DIP
Na stanie27697 pcs
Frequency Control
1
45%
No
No
-
Boost, Flyback, Forward Converter, Full-Bridge, Half-Bridge, Push-Pull
UC2524
Tube
Transistor Driver
-
-40°C ~ 85°C (TA)
Through Hole
16-DIP (0.300', 7.62mm)
16-PDIP
Step-Up, Step-Up/Step-Down
500kHz
2
Positive
8V ~ 40V
RFQ
LTC3731IUH#TRPBF
Analog Devices Inc.
IC REG CTRLR BUCK 32QFN
Na stanie4515 pcs
Enable, Phase Control, Power Good, Soft Start
3
98.5%
Yes
No
-
Buck
LTC3731
Tape & Reel (TR)
Transistor Driver
PolyPhase®
-40°C ~ 85°C (TA)
Surface Mount
32-WFQFN Exposed Pad
32-QFN (5x5)
Step-Down
225kHz ~ 680kHz
3
Positive
3.8V ~ 7V
RFQ
LTC3801ES6#TRPBF
Analog Devices Inc.
IC REG CTRLR BUCK TSOT23-6
Na stanie8674 pcs
Current Limit, Enable
1
100%
No
No
-
Buck
LTC3801
Tape & Reel (TR)
Transistor Driver
-
-40°C ~ 85°C (TA)
Surface Mount
SOT-23-6 Thin, TSOT-23-6
TSOT-23-6
Step-Down
550kHz
1
Positive
2.4V ~ 9.8V
RFQ
XRP6124HVES0.5-F
MaxLinear, Inc.
IC REG CTRLR BUCK SOT23-5
Na stanie5340 pcs
Enable
1
-
No
No
-
Buck
XRP6124
Bulk
Transistor Driver
-
-40°C ~ 125°C (TJ)
Surface Mount
SC-74A, SOT-753
SOT-23-5
Step-Down
100kHz ~ 1MHz
1
Positive
4.5V ~ 30V
RFQ
LTC1628CG#TRPBF
Analog Devices Inc.
IC REG CTRLR BUCK 28SSOP
Na stanie3465 pcs
Enable, Frequency Control, Power Good, Soft Start
2
99.4%
Yes
No
-
Buck
LTC1628
Tape & Reel (TR)
Transistor Driver
-
0°C ~ 85°C (TA)
Surface Mount
16-SSOP (0.209", 5.30mm Width)
16-SSOP
Step-Down
220kHz
2
Positive
3.5V ~ 30V
RFQ
UCC2893PW
Texas Instruments
IC REG CTRLR MULT TOP 16TSSOP
Na stanie10987 pcs
Current Limit, Enable, On Time Control, Ramp, Soft Start
1
70%
No
Yes
-
Flyback, Forward Converter
UCC2893
Tube
Transistor Driver
-
-40°C ~ 85°C (TA)
Surface Mount
16-TSSOP (0.173', 4.40mm Width)
16-TSSOP
Step-Up/Step-Down
250kHz
1
Positive, Isolation Capable
8.5V ~ 16V
RFQ
ISL6439AIBZ
Renesas Electronics America Inc
IC REG CTRLR BUCK 14SOIC
Na stanie4060 pcs
Enable, Phase Control
1
100%
Yes
No
-
Buck
ISL6439
Tube
Transistor Driver
-
-40°C ~ 85°C (TA)
Surface Mount
14-SOIC (0.154', 3.90mm Width)
14-SOIC
Step-Down
600kHz
1
Positive
2.97V ~ 3.63V
RFQ
R1224N502F-TR-FE
Nisshinbo Micro Devices Inc.
18.5V INPUT PWM/VFM STEP-DOWN DC
Na stanie53510 pcs
Enable
1
100%
No
No
-
Buck
R1224
Tape & Reel (TR)
Transistor Driver
-
-40°C ~ 85°C
Surface Mount
SC-74A, SOT-753
SOT-23-5
Step-Down
500kHz
1
Positive
2.3V ~ 18.5V
RFQ
ISL6559CB-T
Renesas Electronics America Inc
IC REG CTRLR BUCK 28SOIC
Na stanie13320 pcs
Current Limit, Enable, Frequency Control, Power Good
4
75%
-
No
-
Buck
ISL6559
Tape & Reel (TR)
PWM Signal
-
0°C ~ 70°C (TA)
Surface Mount
28-SOIC (0.295', 7.50mm Width)
28-SOIC
Step-Down
80kHz ~ 1MHz
4
Positive
4.75V ~ 5.25V
RFQ
L6910G
STMicroelectronics
IC REG CTRLR BUCK 16SOIC
Na stanie10680 pcs
Current Limit, Frequency Control, Phase Control, Power Good, Soft Start
1
100%
Yes
No
-
Buck
L6910
Tube
Transistor Driver
-
-40°C ~ 150°C (TJ)
Surface Mount
16-SOIC (0.154', 3.90mm Width)
16-SO
Step-Down
200kHz
1
Positive
5V ~ 12V
RFQ
TPS40200GDR
Texas Instruments
IC REG CTRLR BUCK 8SOIC
Na stanie39513 pcs
Frequency Control, Soft Start
1
95%
No
No
-
Buck
TPS40200
Tape & Reel (TR)
Transistor Driver
-
-40°C ~ 85°C (TA)
Surface Mount
8-SOIC (0.154', 3.90mm Width)
8-SOIC
Step-Down
35kHz ~ 500kHz
1
Positive
4.5V ~ 52V
RFQ
RC5054AM
Fairchild Semiconductor
IC REG LIN SWITCHING REG/CNTRLR
Na stanie43492 pcs
Current Limit, Frequency Control, Phase Control, Power Good, Soft Start
1
100%
Yes
No
-
Buck
RC5054
Bulk
Transistor Driver
-
0°C ~ 70°C (TA)
Surface Mount
20-SOIC (0.295", 7.50mm Width)
20-SOIC
Step-Down
200kHz
1
Positive
10.8V ~ 13.2V
RFQ
ISL6527CB
Intersil
SWITCHING CONTROLLER
Na stanie5610 pcs
Enable, Phase Control
1
100%
Yes
No
-
Buck
ISL6527
Tube
Transistor Driver
-
0°C ~ 70°C (TA)
Surface Mount
14-SOIC (0.154", 3.90mm Width)
14-SOIC
Step-Down
300kHz
1
Positive
2.97V ~ 3.63V
RFQ
5962-8670408XA
Texas Instruments
UC1845A CURRENT MODE PWM CONTROL
Na stanie942 pcs
-
-
-
-
-
-
-
5962-8670408
Bulk
-
*
-
-
-
-
-
-
-
-
-
RFQ
TL3842BDR-8
Texas Instruments
IC REG CTRLR BST FLYBK PWM 8SOIC
Na stanie159630 pcs
Frequency Control
1
96%
No
No
-
Boost, Flyback, Forward
TL3842
Tape & Reel (TR)
Transistor Driver
-
0°C ~ 70°C (TA)
Surface Mount
8-SOIC (0.154", 3.90mm Width)
8-SOIC
Step-Up, Step-Up/Step-Down
Up to 500kHz
1
Positive
10V ~ 30V
RFQ
SG2524BDW
Microchip Technology
IC REG CTRLR BUCK 16SOIC
Na stanie14050 pcs
Enable, Frequency Control
1
49%
No
Yes
-
-
SG2524
Bulk
Transistor Driver
-
-55°C ~ 125°C (TA)
Surface Mount
16-SOIC (0.154', 3.90mm Width)
16-SOIC
-
50Hz ~ 600kHz
2
Positive
7V ~ 40V
RFQ
UCC2808AQDR-2G4Q1
Texas Instruments
IC REG CTRLR PUSH-PULL 8SOIC
Na stanie9140 pcs
Frequency Control
1
49%
No
No
-
Push-Pull
UCC2808
Bulk
Transistor Driver
Automotive, AEC-Q100
-40°C ~ 125°C (TJ)
Surface Mount
8-SOIC (0.154", 3.90mm Width)
8-SOIC
Step-Up/Step-Down
194kHz
2
Positive
4.1V ~ 15V
RFQ