a8504 Allegro MicroSystems, Inc., a8504 Datasheet - Page 4

• Manufacturer Part Number: a8504
• Description: Wled/rgb Backlight Driver For Medium Size Lcds
• Manufacturer: Allegro MicroSystems, Inc.

Continued on the next page…
A8504
ELECTRICAL CHARACTERISTICS, valid at T
Input Voltage Range
Undervoltage Lockout Threshold
UVLO Hysteresis Window
Supply Current
Error Amplifier
Error Amplifier Open Loop Gain
Error Amplifier Unity Gain Bandwidth
Error Amplifier Transconductance
Error Amplifier Output Sink Current
Error Amplifier Output Source Current
Boost Controller
Switching Frequency
Minimum Switch Off-Time
Logic Input Levels (PWM, SELx, and SKIP pins unless otherwise specified)
Input Voltage Level Low
Input Voltage Level High
Input Leakage Current (PWM, and SKIP
pins)
Input Leakage Current (SELx pins)
Over Voltage Protection (OVP)
Output Overvoltage Rising Limit
OVP Sense Current
OVP Release Current
OVP Leakage Current
Boost Switch
Switch On Resistance
Switch Leakage Current
Switch Current Limit
Characteristics
WLED/RGB Backlight Driver for Medium Size LCDs
V
Symbol
I
I
UGB
t
I
EAsource
R
I
V
OVPleak
UVLOhys
Gm
I
OFFmin
SELleak
I
I
V
I
SWleak
A
EAsink
I
I
OVPH
SWlim
OVPL
f
V
UVLO
V
ds(on)
SUP
V
Ileak
VEA
SW
OVP
IN
IH
IL
EA
EA
A
= –40°C to 85°C, typical values at T
V
Switching at no load, T
Shutdown PWM = V
∆I
V
V
R
R
R
V
V
I
V
V
SW
IN
LED1-8
LED1-8
I(pin)
VOP
SW
SW
FSET
FSET
FSET
COMP
falling
= 1.5 A
= 5 V, T
= 21 V
= 21 V
= 5 V, T
= 13 kΩ, SKIP = V
= 32.4 kΩ, SKIP = V
= 26.1 kΩ, SKIP = V
= ±10 μA
= 1 V
= 0 V
A
A
= 25°C
= 25°C
Test Conditions
IL
A
= 25°C
IL

IL
IH

A
= 25°C, V
IN
115 Northeast Cutoff
1.508.853.5000; www.allegromicro.com
Allegro MicroSystems, Inc.
Worcester, Massachusetts 01615-0036 U.S.A.
= 5 V, unless otherwise noted
Min.
4.2
1.8
1.5
1.6
28
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–280
Typ.
850
280
200
225
0.2
0.1
0.1
60
70
49
44
–
–
5
3
2
1
–
–
–
–
–
–
1
2
Max.
100
5.5
2.2
0.4
32
4
–
–
1
–
–
–
–
–
–
–
–
–
1
–
–
–
–
1
–
–
Units
μA/V
MHz
MHz
MHz
kHz
mΩ
mA
μA
dB
μA
μA
μA
μA
μA
μA
μA
μA
μA
ns
V
V
V
V
V
V
A
4