APEK8651KLP-01-MH Datasheet, PDF (1/34 Pages) Allegro MicroSystems – Low Input Voltage, Adjustable Frequency Dual Synchronous 2A / 2A Buck Regulator with Synchronization, 2x EN, and 2x NPOR

A8651
Low Input Voltage, Adjustable Frequency Dual Synchronous
2 A / 2 A 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 ( f_SW ): 0.35 to 2.2 MHz
• Synchronizes to external clock: 1.2 × to 1.5 × f_OSC
• 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 include VIN 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
C_SYNC DSYNC
V_IN
EN1
C_P1
R_Z1
C_Z1
EN2
C_P2
R_Z2
C_Z2
Typical Application Diagram
5
FSET/SYNC
R_FSET
1
SW1
C_IN1
20 _VIN1
16 _GND
2
PGND1
C_SS1
3 _EN1
17 _COMP1
19 _SS1
4 _ISET1
R_SET1
11 _VIN2
FB1 ¹⁸
A8651
15
NPOR1
10
SW2
C_IN2
9 _PGND2
FB2 ¹⁴
C_SS2
8 _EN2
13 _COMP2
12 _SS2
7 _ISET2
6
NPOR2
R_SET2
L_O1
R_FB1
R_FB2
L_O2
R_FB3
R_FB4
V_OUT1
C_O1
R_PU1
NPOR1
V_OUT2
C_O2
R_PU2
NPOR2
A8651-DS