A8651 Datasheet PDF - Allegro
Part Number | A8651 | |
Description | Low Input Voltage Adjustable Frequency Dual Synchronous 2 A / 2 A Buck Regulator | |
Manufacturers | Allegro | |
Logo | ![]() |
|
There is a preview and A8651 download ( pdf file ) link at the bottom of this page. Total 30 Pages |
Preview 1 page No Preview Available !
A8651
Low Input Voltage, Adjustable Frequency Dual Synchronous
2A / 2A Buck Regulator with Synchronization, 2x EN, and 2x NPOR
Features and Benefits
• AEC-Q100 Qualified
• Operating voltage range: 2.5 to 5.5 V
• UVLO stop threshold: 2.25 V (max)
• Dual outputs with up to 2 A output current per regulator
• Adjustable output voltage as low as 0.8 V
• Internal 80 mΩ high-side switching MOSFET
• Internal 55 mΩ low-side switching MOSFET
• Adjustable switching frequency ( fSW): 0.35 to 2.2 MHz
• Synchronizes to external clock: 1.2 × to 1.5 × fOSC
• 180° phase shift between switching regulators
• Sleep mode supply current less than 5 μA
• Soft start time externally set via the SS pin
• Pre-biased startup capable
• Externally adjustable compensation
• Stable with ceramic output capacitors
• Independent enable inputs and NPOR output pins
• Adjustable current limiting (OCP) for each regulator
• Hiccup mode short-circuit protection (HIC)
• Overvoltage and overtemperature protection
• Open-circuit and adjacent pin short-circuit tolerant
• Short-to-ground tolerant at every pin
Package: 20-pin TSSOP with exposed
thermal pad (suffix LP)
Not to scale
Description
The A8651 is an adjustable frequency, high output current,
PWM regulator that integrates a high-side, P-channel MOSFET
and a low-side, N-channel MOSFET. The A8651 incorporates
current-mode control to provide simple compensation, excellent
loop stability, and fast transient response. The A8651 utilizes
external compensation to accommodate a wide range of power
components to optimize transient response without sacrificing
stability. The A8651 regulates input voltages from 2.5 to 5.5 V,
down to output voltages as low as 0.8 V and is able to supply
up to 2 A of load current per regulator.
The A8651 features include an externally adjustable and
synchronizable switching frequency, an externally-set soft
start time to minimize inrush currents, independent EN inputs,
and independent NPOR outputs with 7.5 ms delay. The sleep
mode current of the A8651 control circuitry is less than 5 μA.
Protection features includeVIN undervoltage lockout (UVLO),
cycle-by-cycle overcurrent protection (OCP), hiccup mode
short-circuit protection (HIC), overvoltage protection (OVP),
and thermal shutdown (TSD). In addition, the A8651 provides
open-circuit, adjacent pin short-circuit, and short-to-ground
Continued on the next page…
Applications:
• GPS/Infotainment
• Automotive audio
• Home audio
• Network and telecom
SYNCin
CSYNC DSYNC
VIN
EN1
CP1
RZ1
CZ1
EN2
CP2
RZ2
CZ2
Typical Application Diagram
5 FSET/SYNC
RFSET
SW1 1
CIN1
20 VIN1
16 GND
2 PGND1
CSS1
3 EN1
17 COMP1
19
4
SS1
ISET1
RSET1
11 VIN2
A8651
FB1 18
NPOR1 15
SW2 10
CIN2
9 PGND2
FB2 14
CSS2
8 EN2
13
12
7
COMP2
SS2
ISET2
NPOR2 6
RSET2
LO1
RFB1
RFB2
LO2
RFB3
RFB4
VOUT1
CO1
RPU1
NPOR1
VOUT2
CO2
RPU2
NPOR2
A8651-DS
Free Datasheet http://www.Datasheet4U.com
|
|
![]() ![]() A8651
Low Input Voltage, Adjustable Frequency Dual Synchronous
2A / 2A Buck Regulator with Synchronization, 2x EN, and 2x NPOR
Detailed Functional Block Diagram
VINx
ISETx
CLKx
OCP
CLAMP ACTIVE
Os cillat or
CLKin
ADJ1
Fsw
ADJ2
ADJ3
ADJ
Slope
Com p
IF VFB > 400m V, Fsw = CLKx
IF VFB < 400m V, Fsw = CLKx/2
IF VFB < 400m V & CLAMP ACTIVE & OCP, Fsw = CLKx/4
VREF
150nA
FBx
TSD
POR
ENx
100K
10ns
UVLOx
EN
+
-
1.65Vtyp
1.25Vtyp
VSSoffs
200m V
ERROR AMP
+
+
-
SSx
GNDx
2K
10uA
20uA
CURRENT
GAIN
PWM
COM P
PWM offs e t
380m V
RESET
DOM
SQ
RQ
M IN_Toff
NON-OVERLAP
VIN
OFF
VIN
OFF
Clam p CLAMP ACTIVE
CURRENT
ENx EN / CLR
OCP
FBx
LATCHED
EN_OCP_COUNT
UVLO
HIC RST
HICCUP
PROTECTIONS
OCP
FAULT
FAULT = 1 IF:
EN = 0 or
UVLO = 1
HICCUP
HICCUP = 1 IF:
FB < 700m V and
7 OCP EVENTS
OFF
OFF
Pad
125ns
FBx
+
-
115% x VREF
111% x VREF
92% x VREF
88% x VREF
OVP
COM P
UV
COM P
OV
UV
1 of 2 regulators shown
7.5m s
Falling
De lay
OFF
UV / OV
A8651
80m
SWx
55m
PGNDx
COM Px
1.5K
NPORx
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
5
Free Datasheet http://www.Datasheet4U.com
![]() Preview 5 Page |
Part DetailsOn this page, you can learn information such as the schematic, equivalent, pinout, replacement, circuit, and manual for A8651 electronic component. |
Information | Total 30 Pages | |
Link URL | [ Copy URL to Clipboard ] | |
Download | [ A8651.PDF Datasheet ] |
Share Link :
Electronic Components Distributor
An electronic components distributor is a company that sources, stocks, and sells electronic components to manufacturers, engineers, and hobbyists. |
SparkFun Electronics | Allied Electronics | DigiKey Electronics | Arrow Electronics |
Mouser Electronics | Adafruit | Newark | Chip One Stop |
Featured Datasheets
Part Number | Description | Manufacturers |
A8651 | The function is Low Input Voltage Adjustable Frequency Dual Synchronous 2 A / 2 A Buck Regulator. | ![]() Allegro |
A8652 | The function is Synchronous USB Buck Regulator. | ![]() Allegro |
A8653 | The function is Synchronous USB Buck Regulator. | ![]() Allegro |
Semiconductors commonly used in industry:
1N4148 |  
BAW56 |
1N5400 |
NE555 | | ||
Quick jump to:
A865
1N4
2N2
2SA
2SC
74H
BC
HCF
IRF
KA |