A8530: Ultracompact 6-Channel Backlight and Flash/Torch White LED Driver

A8530
Ultracompact 6-Channel Backlight
and Flash/Torch White LED Driver
Discontinued Product
This device is no longer in production. The device should not be
purchased for new design applications. Samples are no longer available.
Date of status change: November 1, 2010
Recommended Substitutions:
For existing customer transition, and for new customers or new applications, contact your local Allegro Sales Representative.
NOTE: For detailed information on purchasing options, contact your
local Allegro field applications engineer or sales representative.
Allegro MicroSystems, Inc. reserves the right to make, from time to time, revisions to the anticipated product life cycle plan
for a product to accommodate changes in production capabilities, alternative product availabilities, or market demand. The
information included herein is believed to be accurate and reliable. However, Allegro MicroSystems, Inc. assumes no responsibility for its use; nor for any infringements of patents or other rights of third parties which may result from its use.
A8530
Ultracompact 6-Channel Backlight
and Flash/Torch White LED Driver
Features and Benefits
Description
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The A8530 high efficiency charge pump ICs offer a simple,
low-cost white LED driver solution for driving four display
backlight and two flash/torch/video mode white LEDs. Using
a proprietary control scheme (1×, 1.5×, and 2×), the A8530
can deliver well-matched LED current while maintaining the
highest efficiency and low EMI. The LED current is regulated
over the entire range of Li+ battery voltage to provide uniform
intensity.
LED brightness and on/off can be controlled for 4 display
backlight LEDs and 2 flash/torch LEDs through 2 single-wire
serial interface pins.
The A8530 is available in a very thin profile (0.75 mm nominal
height) 3 mm× 3 mm QFN/MLP 16 pin package. Applications
include:
Proprietary adaptive control scheme (1×, 1.5×, 2×)
0.5% typical LED current matching
2 separate serial interfaces for dimming control
Drives up to 6 white LEDs (4 display backlight, 2 flash/torch)
30 mA per LED channel for display backlight
100 mA per LED channel for flash/torch backlight
320 mA total output current capability
Low EMI design and soft-start function
Short circuit, overvoltage, thermal shutdown protection
0.75 mm very thin profile, 3 mm × 3 mm package
Package: 16 pin QFN/MLP (suffix ES)
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White LED backlights for cellular phones, PDAs
Digital cameras, camcorders
Other portable device white LED backlighting
320 mA WLED flash/torch
Approximate Scale 1:1
Typical Applications
VBATT
2.7 to 5.5 V
CIN
4.7 µF
C1
1 µF
C2
1 µF
RSET
VIN
VOUT
C1+
LED1
C1–
LED2
C2+ A8530
LED3
C2–
LED4
ISET
LED5
ENM
On/Off and
Dimming
Control
ENF
GND
LED6
COUT
4.7 µF
VBATT
2.7 to 5.5 V
C1
1 µF
CIN
4.7 µF
D1
D2
C2
1 µF
D3
D4
D5
RSET
D6
C1+
LED1
On/Off and
Dimming
Control
C1
1 µF
C2
1 µF
RSET
On/Off and
Dimming
Control
VIN
COUT
4.7 µF
VOUT
C1+
LED1
D1
LED2
C2+ A8530
LED3
C2–
LED4
ISET
LED5
ENF
GND
ENF
GND
LED6
Figure 3. 320 mA flash
LED6
D5
D6
Figure 2. 3 × 100 mA flash
VBATT
CIN
1 μF
VIN
VOUT
C1+
LED1
C1–
LED2
C2+ A8530
LED3
C2–
LED4
ISET
LED5
D1
D1-D4 Backlight; D5-D6 Flash
C1–
ENM
COUT
4.7 µF
C1–
D1-D4 Backlight; D5-D6 Flash
VBATT
2.7 to 5.5 V
8530-DS, Rev. 1
VOUT
ENM
Figure 1. 4 × 30 mA backlight with 2 × 100 mA flash
CIN
4.7 µF
VIN
LED2
C2+ A8530
LED3
C2–
LED4
ISET
RSET
ENF
D2
D3
D4
D5
LED5
ENM
On/Off and
Dimming
Control
D1
GND
LED6
D6
D1-D4 Main; D5-D6 Flash
VIN>Vf(max)+0.2 V, Vf = LED forward drop
Figure 4. High efficiency current sink
Ultracompact 6-Channel Backlight
and Flash/Torch White LED Driver
A8530
Functional Block Diagram
C2
1 µF
C1
1 µF
C1 –
C1+
C2–
C2+
VOUT
VIN
Fractional Charge Pump
(1×, 1.5×, and 2×)
CIN
4.7 µF
COUT
4.7 µF
+
–
ENM
Control, Clock,
and Reference
ENF
Minimum Select
LED1
LED2
LED3
Current Mirror
LED4
LED5
IREF
LED6
IREF
+
–
ISET
+
–
+
–
+
–
+
–
+
–
+
–
RSET
GND
Absolute Maximum Ratings
Input or Output Voltage
VIN, VOUT, C1+, C1– , C2+, C2– to GND ..................... –0.3 to 6 V
All other pins..................................................... –0.3 to VIN + 0.3 V
VOUT Short Circuit to GND ....................................................Continuous
Operating Ambient Temperature, TA ..................................... –40°C to 85°C
Junction Temperature, TJ(max).............................................................. 150°C
Storage Temperature, TS ................................................... –55°C to 150°C
Package Thermal Characteristics
RθJA = 47 °C/W, on a 4-layer board based on JEDEC spec
Additional information is available on the Allegro Web site.
Device package is lead (Pb) free, with 100% matte tin leadframe
plating.
Use the following complete part number when ordering:
Part Number
Packaging*
Package Type
A8530EESTR-T
7-in. reel, 1500 pieces/reel
ES, 3 × 3 mm MLP-16
*Contact Allegro for additional packing options.
Allegro MicroSystems, Inc.
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
www.allegromicro.com
2
Ultracompact 6-Channel Backlight
and Flash/Torch White LED Driver
A8530
Pin-out Diagram
13 C1–
14 VIN
8
9
LED4
4
10 LED2
7
ENF
11 LED1
EP
LED5
3
6
ISET
12 GND
5
2
ENM
1
LED6
C2+
VOUT
15 C2–
16 C1+
ES Package
LED3
(Top View)
Terminal List Table
Name
C1–
C1+
C2–
C2+
ENF
ENM
EP
GND
Number
13
16
15
1
4
5
–
12
ISET
3
LED1, LED2,
LED3, and LED4
8, 9, 10,
and 11
LED5 and LED6
6 and 7
VIN
14
VOUT
2
Function
Negative terminal of capacitor C1. Connect capacitor C1 between C1+ and C1–.
Positive terminal of capacitor C1.
Negative terminal of capacitor C2
Positive terminal of capacitor C2. Connect capacitor C2 between C2+ and C2–.
Enable and dimming control input for flash/torch.
Enable and dimming control input for display backlight.
Exposed metal pad on bottom side. Connect this to ground plane for better thermal performance.
Ground.
Connect RSET resistor to ground to set desired constant current through backlight LEDs.
ILED(max) = 220 x 0.6 V / RSET
Current sink for display backlight LEDs. If not used, connect to VOUT, but do not leave open. If left
open, the IC works in 2 × mode.
Current sink for flash/torch LEDs. If not used, connect to VOUT, but do not leave open. If left open,
the IC works in 2 × mode.
Power supply voltage input.
Charge pump output voltage source for display backlight and flash/torch LED anodes.
Connect a 4.7 μF capacitor, COUT, between VOUT and GND (see figures 1 through 4).
Allegro MicroSystems, Inc.
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
www.allegromicro.com
3
Ultracompact 6-Channel Backlight
and Flash/Torch White LED Driver
A8530
ELECTRICAL CHARACTERISTICSa VIN = ENM = 3.6 V, ENF = GND, C1 = C2 = 1 μF, CIN = COUT = 4.7 μF, RSET = 6.49 kΩ,
TA = –40°C to +85°C; typical values are at TA = 25°C; unless otherwise noted
Characteristics
Symbol
VIN
Input Voltage Range
Undervoltage Lockout Threshold
UVLO Hysteresis Window
VUVLO
VUVLOHYS
Test Conditions
VIN falling
Switching in 1.5 × or 2.0 × mode; TA = 25°C
Min.
2.7
Typ. Max. Units
–
5.5
V
2.25
–
–
2.45
60
6
2.60
–
–
V
mV
mA
Quiescent Current
IQ
–
0.1
2
μA
Soft-start Completion Time
tss
–
2.0
–
ms
ISET Bias Voltage
VISETBIAS
–
0.6
–
V
ISET Leakage in Shutdown
ISET Current Range
ISET to LEDx Current Ratio for LED1 through LED4
VISETLKG
ISET
ILEDx/IISET
100% setting, ISET = 60 μA
–
40
–
0.01
–
220
1
140
–
μA
μA
A/A
ILED56MAX
Default 100% setting when ENF is enabled
92
100
108
mA
–
±1.6
–
%
100% Output Current for LED5 and LED6
ILED Accuracy for LED1 through LED4b
LED Current Matching for LED1 through
ENF = ENM = GND; TA = 25°C
EILED14ERR ENF = GND, ENM = VIN
LED4c
LED Current Matching for LED5 and LED6c
ΔILED14
ENF = GND, ENM = VIN
–
±0.5
–
%
ΔILED56
ENF = VIN, ENM = GND, 100%
–
±0.5
–
%
Regulation Voltage at LEDx (1.5 × and 2 × modes)
VREG
ENF = ENM = VIN
–
250
–
mV
1x mode to 1.5x or 1.5x to 2x mode transition voltage at LEDx
Vtrans
VLEDx falling
–
150
–
mV
Transition–Dropout Deltad
ΔVdr
Measured as Vtrans – Vdropout
–
40
–
mV
1× mode (VIN – VOUT) / IOUT
–
1
–
Ω
1.5× mode (1.5 × VIN – VOUT) / IOUT
2× mode (2 × VIN – VOUT) / IOUT
ENF = ENM = GND, VIN = 5.5 V
–
–
–
2.5
5
0.01
–
–
1
Ω
Ω
μA
–
1
–
MHz
–
–
6.0
V
V
Open Loop Output Resistancee
LED Leakage in Shutdown
Oscillator Frequency
ROUT
VLEDLKG
fosc
Output Overvoltage Protection (guaranteed by design)
Vovp
Open circuit at any LED that is programmed
to be in the ON state
ENF and ENM Input High Threshold
VIH
Input high logic threshold
1.4
–
–
ENF and ENM Input Low Threshold
VIL
Input low logic threshold
–
–
0.4
V
Input High Current
IIH
VIH=VIN
–
–
1
μA
Input Low Current
IIL
VIL= GND
ENM and ENF Pulse Low Time (figure 6)
tLO
ENM and ENF Pulse High Time (figure 6)
–
–
1
μA
0.5
–
250
μs
μs
0.5
–
–
50
–
–
μs
Falling edge of ENF and/or ENM
–
0.5
–
ms
20oC hysteresis
–
165
–
oC
tHI
ENM and ENF Initial Pulse High Time (figure 6)
tINIHI
First ENM or ENF pulse after shutdown
Shutdown or Dimming Reset Delay
tSHDN
Thermal Shutdown Threshold
TTSD
aSpecifications
for the range TA = –40°C to 85°C are guaranteed by design.
bI
LED accuracy is defined as ( ISET × 220 – ILEDAVG ) / (ISET × 220).
cLED current matching is defined as (I
LEDx – ILEDAVG) / ILEDAVG .
dDropout voltage V
dropout is defined as LEDx-to-GND voltage at which ILEDx drops 10% below the value of ILEDx when VLEDx = 300 mV.
eThe open loop output resistance, R
OUT, for 1.5 × mode is measured when one of the LEDx pins is tied to ground or open (thus its voltage
is always less
than 80 mV).
Allegro MicroSystems, Inc.
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
www.allegromicro.com
4
Ultracompact 6-Channel Backlight
and Flash/Torch White LED Driver
A8530
Performance Characteristics
Tests performed using application circuit shown in figure 1
TA = 25°C, VIN = 3.6 V (unless otherwise noted)
Efficiency versus Supply Voltage
Efficiency versus Supply Voltage
for LED1 through LED4, in parallel
for LED5 and LED6, in parallel
95
95
90
90
85
85
80
VFx = 3.4 V
IFx = 20 mA
75
Eff (%)
Eff (%)
80
VFx = 3.7 V
IFx = 100 mA
70
75
70
65
65
VFx = 3.1 V
IFx = 10 mA
60
VFx = 3.2 V
IFx = 50 mA
60
55
55
2.7
3.1
3.5
3.9
4.3
4.7
5.1
2.7
5.5
3.1
3.5
3.9
VIN (V)
Logic Level
4.7
5.1
5.5
RSET versus ILED
35
1.2
30
1.1
ILED / Channel (mA)
VHI
1.0
V ENx (V)
4.3
VIN (V)
0.9
0.8
VLO
0.7
25
RSET = 6.65 kΩ
20
RSET = 8.87 kΩ
15
10
5
0.6
0
0.5
2.7
3.1
3.5
3.9
4.3
4.7
5.1
4
5.5
6
8
10
12
14
16
RSET (kΩ)
VIN (V)
Dimming on ENM
Enable Pulses versus Total Current, LED1 through LED4
VENM
Symbol
C1
C2
t
C1
Parameter
VENM
ILED14
time
Units/Division
0.5 V
50 mA
50 ms
ILED14
C2
t
Allegro MicroSystems, Inc.
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
www.allegromicro.com
5
Ultracompact 6-Channel Backlight
and Flash/Torch White LED Driver
A8530
Performance Characteristics
Tests performed using application circuit shown in figure 1
TA = 25°C, VIN = 3.6 V (unless otherwise noted)
LED5-6 ON, 1.5× mode
VIN = 3.2 V, IOUT = 200 mA, VF = 3.1 V
VOUT
C3
Symbol
C3
C4
t
Parameter Units/Division
20 mV
VOUT Ripple
IIN Ripple
50 mA
time
500 ns
IIN
C4
t
LED5-6 ON, 2× mode
VOUT
VIN = 2.7 V, IOUT = 200 mA, VF = 3.1 V
C3
Symbol
C3
C4
t
Parameter Units/Division
VOUT Ripple
20 mV
50 mA
IIN Ripple
time
500 ns
IIN
C4
t
LED1-4 ON, 1.5× mode
VIN = 3.6 V, IOUT = 80 mA, VF = 3.4 V
VOUT
C3
Symbol
C3
C4
t
VOUT
Parameter Units/Division
VOUT Ripple
20 mV
IIN Ripple
50 mA
time
500 ns
IIN
C4
t
Allegro MicroSystems, Inc.
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
www.allegromicro.com
6
Ultracompact 6-Channel Backlight
and Flash/Torch White LED Driver
A8530
Performance Characteristics
Tests performed using application circuit shown in figure 1
TA = 25°C
Turn ON LED1-6 in 1X Mode
Turn ON LED1-6 in 2X mode
VIN = 4.0 V, IOUT = 280 mA
VIN = 2.7 V, IOUT = 280 mA
VENF and VENM
VENF and VENM
VOUT
C1
IOUT
IOUT
C2
VOUT
C1
C2
C3
C3
t
Symbol
C1
C2
C3
t
t
Parameter
Units/Division
VENF and VENM
2.00 V
2.00 V
VOUT
IOUT
100 mA
time
0.5 ms
Symbol
C1
C2
C3
t
Parameter
Units/Division
VENF and VENM
2.00 V
2.00 V
VOUT
IOUT
100 mA
time
0.5 ms
Turn ON LED1-6 in 1.5X Mode
VIN = 3.0 V, IOUT = 280 mA
VENF and VENM
VOUT
C1
IOUT
C2
C3
t
Symbol
C1
C2
C3
t
Parameter
Units/Division
VENF and VENM
2.00 V
2.00 V
VOUT
IOUT
100 mA
time
0.5 ms
Allegro MicroSystems, Inc.
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
www.allegromicro.com
7
Ultracompact 6-Channel Backlight
and Flash/Torch White LED Driver
A8530
Application Information
Setting LED Current
Use the following formula to set the display backlight LED full
current (100%) using RSET on LED1 through LED4. The maximum current through one LED should not exceed 30 mA:
RSET = 0.6 V × 220 / ILEDx
where RSET is in Ω and ILEDx in amperes.
The default flash/torch current on LED5 and LED6 is set internally to 100 mA per channel. When both the display backlight
and the flash/torch LEDs are on, the maximum current output
from LED1 through LED4 is 30 mA per channel. The output current of the flash/torch LEDs (LED5 and LED6) can be adjusted
by serial dimming at the ENF pin within 1 ms after ENF is pulled
high.
Transitions Between 1× and 1.5× or 2× Modes
The A8530 adaptively selects operating mode. When VIN is sufficiently high to maintain VLEDx > 150 mV, the A8350 operates
95
When the A8530 switches from 1× to 2× mode, it first switches
to 1.5× mode for a typical duration of 1 ms before entering
2× mode.
When operating in 1.5× mode, if VOUT < VIN, then the IC
switches back to 1× mode every 130 ms, and then reenters 1.5×
mode again if necessary.
Transitions Between 1.5× and 2× Modes
The transition from 1.5× to 2× mode depends upon dropout
conditions.
When operating in 2× mode, the IC switches back to 1.5× mode
every 130 ms, and then reenters 2× mode again if necessary.
Furthermore, when in 2× mode, whenever a channel disabling
is sensed (that is, whenever ENM is held low for > 0.5 ms with
ENF high, or vice versa), the IC automatically reverts to 1.5×
mode, and then reenters 2× mode again if necessary.
Dimming
90
Display Backlight LED1 through LED4 Dimming The display
backlight LEDs (LED1 through LED4) brightness and on/off can
be controlled using digital input at the ENM pin. The ENM pin
accepts one-wire serial pulse input to enable the A8350 and to set
up to 11 dimming levels, from 100% down to 5%.
85
75
70
65
VFx = 3.4 V
IFx = 20 mA
VIN Rising
VIN Falling
80
Eff (%)
in 1 × mode unless, as VIN drops, the LEDx nodes fall below
the 150 mV threshold. When VLEDx falls below 150 mV, the IC
enters 1.5× mode.
When ENM is initially pulled up from shutdown, after a softstart, the current for the backlight LEDs is programmed to 100%
of the setting current, which is determined by the current through
the ISET pin. Each subsequent pulse reduces the LED current
by 10%, and the 10th pulse reduces the current by 5%. The next
pulse restores 100% (full) brightness. Figure 6 shows the timing
diagram for ENM control.
60
55
2.7
3.1
3.5
3.9
4.3
4.7
5.1
5.5
VIN (V)
Figure 5. Mode change transitions
ENM (LED1-4) or
ENF (LED5-6)
0
tHI(Init)
1
2
3
4
tSS
100%
IILED(1-4) or
IILED(5-6)
5
6
t LO
90%
80%
70%
60%
7
8
9
10
11
tSHDN
t HI
100% 90%
50%
SHDN
40%
30% 20%
10%
5%
SHDN or
Dimming
Reset
Figure 6. Single-Wire Serial Dimming Control; at pins ENF and ENM.
Allegro MicroSystems, Inc.
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
www.allegromicro.com
8
Ultracompact 6-Channel Backlight
and Flash/Torch White LED Driver
A8530
Flash/Torch LED5 and LED6 Operation The flash/torch LEDs
(LED5 and LED6) brightness and on/off can be controlled using
digital input at ENF pin. ENF accepts one-wire serial pulse input
to enable the A8530 and to set up to 11 dimming levels, from
100 mA (the default 100% level) down to 5 mA.
When the ENF pin is initially pulled up from shutdown, after a
soft-start (if the IC is not yet soft-started using the ENM pin),
the current for LED5 and LED6 is, by default, programmed to
100 mA, corresponding to 100% of flash/torch brightness. Each
subsequent pulse reduces the LED current by 10 mA, and the
10th pulse reduces the current by 5 mA. The next pulse then
restores to 100 mA (full) output current per channel. Figure 6
shows the timing diagram for ENF.
Absolute Level Operation Some applications require dimming
to a specific level, regardless of the present level of dimming.
For example, if the IC should dim to 30%, this can be done with
7 steps, as shown in figure 6, irrespective of the dimming level
in effect. This can be achieved by pulling corresponding ENx
pin low for time greater than tSHDN and then applying pulses as
shown in figure 6 (7 for 30% dimming). If the pulses are applied
within 2 to 3 ms, the display flicker is not visible. The procedure
is shown in figure 7.
Shutdown
When the ENM pin is pulled low for 0.5 ms or longer, the display
backlight channels are shut off and dimming is reset to 100%
upon the next ENM going high edge. When the ENF pin is
pulled low for 0.5 ms or longer, the brightness of the flash/torch
channels is reset to 100 mA upon the next ENF going high edge.
When both ENM and ENF are pulled low for 0.5 ms or longer,
the A8530 enters the shutdown mode.
Short Circuit Protection
The A8530 is protected against short circuits on the output. When
VOUT is externally pulled below 1.2 V, the IC enters Short Circuit
mode. The A8530 resumes normal operation when the short
circuit is removed.
Rapid pulse pattern
∆t > tSHDN
C1
VENM
ENx pulled low
Symbol
C1
C2
C3
t
Parameter
VENM
VOUT
IOUT
time
Units/Division
2.00 V
2.00 V
50 mA
0.5 ms
C2
VOUT
100%
C3
ISET counter resets
30%
IOUT
t
Figure 7. Absolute Dimming Level Setting. With ENM pulled low longer the tSHDN,
pulsing the corresponding ENx pin sets an absolute target level.
Allegro MicroSystems, Inc.
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
www.allegromicro.com
9
Ultracompact 6-Channel Backlight
and Flash/Torch White LED Driver
A8530
ing LED group (main or sub) is enabled.
Note: In shutdown mode (ENM = ENS = 0 V for > 0.5 ms), the
total leakage current is < 1μA.
Thermal Shutdown
Overvoltage Protection
The A8530 is protected up to 4.9 V supply voltage, against
accidental overvoltage caused by an open LED. When any LED
opens, VOUT will increase till 6 V. Remaining LEDs will continue
to function normally. Normal operation will be resumed when the
fault is removed.
The IC is internally protected against overtemperature. The
overtemperature limit is set to 165°C nominal. The IC shuts down
when the junction temperature exceeds 165°C and automatically
turns on again when the IC cools.
LED Disconnection
Every LEDx pin has a disable subcircuit, as shown in figure 8.
The A8530 compares the voltage on each LED pin, and if
the voltage on the pin is greater than either VOUT – 0.4 V or
VIN – 0.4 V, then the corresponding LED pin is disabled.
Component Selection
Ceramic capacitors with X5R or X7R dielectric are recommended for the input capacitor, CIN, the output capacitor, COUT,
and the charge pump capacitors, C1 and C2.
If any WLED is not used, connect the corresponding pin to
VOUT. Never leave open any unused WLED pin. LED pins will
sink 20 μA typical when connected to VOUT and the correspond-
A8530
VBATT
VIN
1×, 1.5×, 2×
Charge Pump
VOUT
CIN
COUT
LED Disable Block
One of six blocks
–
+
VIN – 0.4
LED1
–
+
D1
D2
VOUT – 0.4
Current
Sink
D3
D4
D5
D6
Figure 8. LED disable subcircuit. Subcircuit for one LEDx pin shown. A similar block is
connected to each LEDx pin.
10
Allegro MicroSystems, Inc.
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
www.allegromicro.com
Ultracompact 6-Channel Backlight
and Flash/Torch White LED Driver
A8530
Package ES, 3 × 3 mm 16-Pin QFN/MLP
0.30
3.00 ±0.15
0.90
16
1
2
A
0.50
16
1
3.00 ±0.15
1.70
3.10
1.70
17X
D
SEATING
PLANE
0.08 C
+0.05
0.25 –0.07
C
3.10
C
PCB Layout Reference View
0.75 ±0.05
0.50
For reference only
(reference JEDEC MO-220WEED)
Dimensions in millimeters
Exact case and lead configuration at supplier discretion within limits shown
+0.15
0.40 –0.10
A Terminal #1 mark area
B
1.70
2
1
16
1.70
B Exposed thermal pad (reference only, terminal #1
identifier appearance at supplier discretion)
C Reference land pattern layout (reference IPC7351
QFN50P300X300X80-17W4M);
All pads a minimum of 0.20 mm from all adjacent pads; adjust as
necessary to meet application process requirements and PCB layout
tolerances; when mounting on a multilayer PCB, thermal vias at the
exposed thermal pad land can improve thermal dissipation (reference
EIA/JEDEC Standard JESD51-5)
D Coplanarity includes exposed thermal pad and terminals
Copyright ©2005-2008, Allegro MicroSystems, Inc.
The products described here are manufactured under one or more U.S. patents or U.S. patents pending.
Allegro MicroSystems, Inc. reserves the right to make, from time to time, such departures from the detail specifications as may be required to permit improvements in the performance, reliability, or manufacturability of its products. Before placing an order, the user is cautioned to verify that the
information being relied upon is current.
Allegro’s products are not to be used in life support devices or systems, if a failure of an Allegro product can reasonably be expected to cause the
failure of that life support device or system, or to affect the safety or effectiveness of that device or system.
The information included herein is believed to be accurate and reliable. However, Allegro MicroSystems, Inc. assumes no responsibility for its use;
nor for any infringement of patents or other rights of third parties which may result from its use.
For the latest version of this document, visit our website:
www.allegromicro.com
11
Allegro MicroSystems, Inc.
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
www.allegromicro.com
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