A8590 Datasheet, PDF (4/38 Pages) Allegro MicroSystems – Wide Input Voltage, 2.4 MHz, 3.0 A Asynchronous Buck Regulator With Low-IQ Standby, Sleep Mode, External Synchronization, and NPOR Output

A8590
Wide Input Voltage, 2.4 MHz, 3.0 A Asynchronous Buck Regulator With
Low-IQ Standby, Sleep Mode, External Synchronization, and NPOR Output
VIN
VREG
LDO
BIAS >
LDO_OUT + 50 mV
VREG
3.6 V
BG
5.75 V
UVLO
1.205 V
REGOV
5.0 V
Q
2 V, 4.1 V
BOOT REG
BOOT
OFF
EN
BOOT
REG
OC
250 mA
SLEEP
FSET
PWM/PFM
FB
DELAY
84 µs↓
2.90 V
Digital _POR
400 mV
PWM
BOOT
OFF
BOOT
FAULT
F > 1.2x
sleep
PWM
PWM
I_SENSE
F ^blankOn
F/2 minOff
F/4
750 mA
PWML
Current
PFM _Comp
2x
G_CSA
SQ
TG
RQQ
maxDuty
DELAY
2048↓
PFM
Controller
FB < 0.8 V
BOOT < 4.1 v
VREG
BG
I_FB
Error
Amplifier
sleep
PWM
CLAMP
OCL
sleep
PWM
800 mV
400 mV
sleep
PWM
maxDuty
compFalling
IDLE/START
RECOVERY
CONTROL
ssDischarge
20 µA
FB < 700 mV
FB < 880 mV
OCL
swLoDet
DIODEOK
BOOT FAULT
REGOV
FAULT
LOGIC
(See Fault
Table)
HIC SET
HIC RST
sleep
PWM
UVLO
POR
TSD
PULL DOWN
BOOT OFF
FB < 700 mV
FB > 880 mV
FB < 740 mV
HICCUP
LOGIC
HICCUP
DELAY
7.5 ms↓
BIAS
BOOT
SW
swLoDet
DIODEOK
COMP
5 µA
1 kΩ
SS
2 KΩ
OFF
NPOR
Functional Block Diagram
Allegro MicroSystems, LLC
4
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com