A8589 Datasheet, PDF (1/40 Pages) Allegro MicroSystems – Wide Input Voltage, 2.4 MHz, 2.5 A Asynchronous Buck Regulator With Low-IQ Standby, Sleep Mode, External Synchronization, and NPOR Output

A8589
Wide Input Voltage, 2.4 MHz, 2.5 A Asynchronous Buck Regulator
With Low-IQ Standby, Sleep Mode, External Synchronization, and NPOR Output
FEATURES AND BENEFITS
• Automotive AEC-Q100 qualified
• Withstands surge voltages up to 40 V
• Operates as low as 3.4 V_IN (typ) with V_IN decreasing
• Utilizes pulse frequency modulation (PFM) to draw only
tens of microamperes from VIN while maintaining
keep-alive VOUT
• PWM/PFMn mode control input pin
• Delivers up to 2.5 A of output current with integrated
110 mΩ high voltage MOSFET
• SLEEPn input pin commands ultra-low current
shutdown mode
• Adjustable output voltage with ±1.0% accuracy from 0°C
to 85°C, ±1.5% from –40°C to 150°C
• Programmable switching frequency: 250 kHz to 2.4 MHz
• Synchronization capability: applying a clock input to the
PWM/PFMn input pin will increase the PWM frequency
• Active low, power-on reset (NPOR) open-drain output
• Maximized duty cycle for low dropout
Continued on the next page…
Package: 16-pin TSSOP with exposed
thermal pad (suffix LP)
Not to scale
DESCRIPTION
Designed to provide the power supply requirements of next
generation car audio and infotainment systems, the A8589
provides all the control and protection circuitry to produce a
high current regulator with ±1.0% output voltage accuracy. The
A8589 employs pulse frequency modulation (PFM) to draw
less than 50 µA from 12V_IN while supplying 3.3 V/40 µA.
After startup, the A8589 operates down to at least 3.6 V_IN
(V_IN falling).
Features of the A8589 include a PWM/PFMn mode control
input to enable PWM (logic high) or PFM (logic low). If
the PWM/PFMn input is driven by an external clock signal
higher than the base frequency ( f_OSC ) the PWM frequency
synchronizes to the incoming clock frequency. The SLEEPn
input pin commands an ultra-low current shutdown mode
requiring less than 5 µA for internal circuitry and 10 µA (max)
for MOSFET leakage at 16 V_IN , 85ºC. The A8589 has external
compensation to accommodate a wide range of frequencies
and external components, and provides a power-on reset
(NPOR) signal validated by the output voltage.
Continued on the next page…
APPLICATIONS:
• Automotive:
□□Instrument
clusters
□□Audio Systems
• Home Audio
□□Navigation
□□HVAC
V
IN
C
P
R
Z
C
Z
EN
Mode
1 _VIN
2 _{VIN U1}
15
SW ₁₄
SW
C
IN
A8589
5
GND
13
GND
16
BOOT
C
BOOT
C
SS
R
FSET
9 _COMP
3
SS
8 _FSET
12
VREG
C
VREG
11
BIAS
10
FB
R
FB2
L
O
D1
R
FB1
C
FB
4 _SLEEP
6 _PWM/PFM
7
POK
Typical Application Diagram
V
OUT
C
O
POK
A8589-DS, Rev. 2