AS3630 Datasheet

AS3630
8A Supercap Flash Driver
General Description
The AS3630 is an inductive high efficient 4MHz dual DCDC step
up converter with several sources. It supports the charging of a
Supercap, its voltage balancing and a highly efficient DCDC step
up from the Supercap to the LED and from VIN to the LED to
power the flash LED with up to 8A. The AS3630 supports the
pre-charging of the Supercap (to VIN) to reduce the startup time
for the flash without reducing the lifetime of the Supercap.
The system concept supports an immediate torch function
without first charging the Supercap.
The AS3630 includes flash timeout, over- undervoltage,
overtemperature and LED short circuit protection.
The AS3630 is controlled by an I²C interface for adjustment of
the currents and timings, set the end of charge voltage and
measure the Supercap and LED parameters through the internal
ADC. A dedicated TXMASK/TORCH input can be used for a torch
button -or- reducing the battery current if a RF PA is operated
at the same time (TX Masking). A hardware enable pin -ON can
be used as a reset input.
The AS3630 is available in a space-saving WL-CSP 5x5 balls
package measuring only 2.5x2.5x0.6mm and operates over the
-30ºC to +85ºC temperature range.
Figure AS3630 – 1:
Key Benefits and Features
Benefits
Features
Reduce Supercap size
Dual high efficiency boost converter with soft start
allows small coils
Instantaneous Torch operation for improved user
experience
Immediate Torch functions with charging of the
Supercap
Tiny external coils
4MHz fixed frequency DCDC
System Safety
10bit ADC converter for system monitoring with
Protection functions:
Automatic Flash Timeout timer to protect the LED
Overvoltage and undervoltage Protection
LED (NTC) and device Overtemperature Protection
LED short/open circuit protection
Improved thermal performance (ground = heat sink)
Flash LED(s) cathode connected to ground:
8A Supercap Flash Driver
AS3630 – 1
Benefits
Features
Fine control of current to fit to applications
LED currents (fully adjustable by interface)
• 8A for 33ms and 6A for 120ms (Flash), 2.9mA 272mA for torch
• 1mA-8mA indicator current
Full control and hardware ON pin for easier system
integration
I²C Interface with Interrupt output and ON pin
The device is ideal for Flash/Torch for mobile phones, DSC and
Tablets.
Applications
Figure AS3630 – 2:
Typical Operating Circuit
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Typical Operating Circuit: Shows the main function blocks of the AS3630.
AS3630 – 2
8A Supercap Flash Driver
Pin Assignment
Figure AS3630 – 3:
Pin Assignments (Top View)
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8A Supercap Flash Driver
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AS3630 – 3
Pin Description
Figure AS3630 – 4:
Pin Description
Pin Number
Pin Name
Description
A1
STROBE
A2
NTC
LED temperature sensor input - connect to NTC and connect its
GND with a separate ground wire to AGND
A3
SDA2
Digital input, open drain output - serial data input/output for I²C
interface (needs external pullup resistor)
A4
SCL2
Digital Input3 - serial clock input for I²C mode
A5
AGND
B1
VSUPERCAP
B2
IND_OUT
Digital input with pulldown to control strobe time for flash
function1
Analog ground - connect to ground (GND)
Supercap connection
Indicator LED current source output
B3
TXMASK/TORCH
Function 1
• “TXMASK” Connect to RF power amplifier enable signal reduces currents during flash to avoid a system shutdown
due to parallel operation of the RF PA and the flash driver.
Function 2
• “TORCH” Operate torch current level without using the I²C
interface to operate the torch without need to start a
camera processor (if the I²C is connected to the camera
processor.
B4
ON
Digital Input active high - a logic 1 enables of the AS3630; a logic
0 resets the AS3630
B5
VIN
Positive supply voltage input - connect to supply and make a
short connection to input capacitor CVIN and to coil LDCDC1
C1
BAL
Supercap balance pin - balances both single capacitors inside the
Supercap
C2
SW2
DCDC converter 2 switching node - make a short connection to
the coil LDCDC2 and connect all SW2 pins together on top plane
C3
PGND
Power ground - connect to ground (GND) and connect all PGND
pins together on top plane
C4
INT
Open drain interrupt output - active low (needs external pullup
resistor)
C5
VDCDC
DCDC converter 1 and 2 output capacitor - make a short
connection to CVOUT1 and connect all VDCDC pins together as
short as possible
AS3630 – 4
8A Supercap Flash Driver
Pin Number
Pin Name
Description
D1
VDCDC
DCDC converter 1 and 2 output capacitor - make a short
connection to CVOUT1 and connect all VDCDC pins together as
short as possible
D2
SW2
DCDC converter 2 switching node - make a short connection to
the coil LDCDC2 and connect all SW2 pins together on top plane
D3
PGND
Power ground - connect to ground (GND) and connect all PGND
pins together on top plane
D4
SW1
DCDC converter 1 switching node - make a short connection to
the coil LDCDC1 and connect all SW1 pins together on top plane
D5
LED_OUT
Flash LED current source output and connect all LED_OUT pins
together on top plane
E1
VDCDC
DCDC converter 1 and 2 output capacitor - make a short
connection to CVOUT1 and connect all VDCDC pins together as
short as possible
E2
SW2
DCDC converter 2 switching node - make a short connection to
the coil LDCDC2 and connect all SW2 pins together on top plane
E3
PGND
Power ground - connect to ground (GND) and connect all PGND
pins together on top plane
E4
SW1
DCDC converter 1 switching node - make a short connection to
the coil LDCDC1 and connect all SW1 pins together on top plane
E5
LED_OUT
Flash LED current source output and connect all LED_OUT pins
together on top plane
1. Application Information: The pin STROBE is usually connected directly to the camera processor.
2. When SCL and SDA exchanged, the AS3630 uses a different I²C address and the functionality of SCL/SDA is also exchanged - see “I²C Address
Selection” on page 43.
3. Only input: The AS3630 does not perform clock stretching.
8A Supercap Flash Driver
AS3630 – 5
Stresses beyond those listed under “Absolute Maximum
Ratings“ may cause permanent damage to the device. These are
stress ratings only. Functional operation of the device at these
or any other conditions beyond those indicated under
“Operating Conditions” is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect
device reliability.
Absolute Maximum Ratings
Figure AS3630 – 5:
Absolute Maximum Ratings
Parameter
Min
Max
Units
VIN, SDA, SCL, ON, STROBE,
TXMASK/TORCH, INT, IND_OUT, NTC
and BAL to GND
-0.3
+7.0
V
SDA, SCL, ON, STROBE,
TXMASK/TORCH, INT, IND_OUT, NTC to
GND
-0.3
VIN + 0.3
V
VDCDC, SW1, SW2, VDCDC, LED_OUT and
VSUPERCAP to GND
-0.3
+11
V
VDCDC to SW1
VDCDC to SW2
VDCDC to LED_OUT
VSUPERCAP to BAL
-0.3
AGND, PGND to GND
0.0
-100
Input Pin Current without causing
latchup
Comments
V
Diode between
• VDCDC and SW1
• VDCDC and SW2
• VDCDC and LED_OUT
• VSUPERCAP and BAL
0.0
V
Connect AGND and PGND to GND
directly below the ball (short
connection required)
+100
+IIN
mA
Norm: EIA/JESD78
Continuous Power Dissipation (TA = +70ºC)
Continuous power dissipation
Continuous power dissipation derating
factor
2770
mW
37
mW/ºC
PT1
PDERATE2
Electrostatic Discharge
ESD HBM
±2000
V
Norm: JEDEC JESD22-A114F
ESD MM
±100
V
Norm: JEDEC JESD 22-A115-B
AS3630 – 6
8A Supercap Flash Driver
Parameter
Min
Max
Units
Comments
Temperature Ranges and Storage Conditions
Junction Temperature
Storage Temperature Range
Humidity
Body Temperature during Soldering
Moisture Sensitivity Level (MSL)
+150ºC internally limited only
during flash (max. 20000s)
+125
ºC
-55
+125
ºC
5
85
%
Non condensing
+260
ºC
According to IPC/JEDEC J-STD-020
MSL 1
Represents a max. floor life time of
unlimited
1. Depending on actual PCB layout and PCB used.
2. PDERATE derating factor changes the total continuous power dissipation (PT) if the ambient temperature is not 70ºC. Therefore for e.g.
TAMB=85ºC calculate PT at 85ºC = PT - PDERATE * (85ºC - 70ºC)
8A Supercap Flash Driver
AS3630 – 7
Electrical Characteristics
All limits are guaranteed. The parameters with min and max
values are guaranteed with production tests or SQC (Statistical
Quality Control) methods.
V VIN = +2.5V to +4.8V, TAMB = -30ºC to +85ºC, unless otherwise
specified. Typical values are at V BAT = +3.7V, TAMB = +25ºC,
unless otherwise specified.
Figure AS3630 – 6:
Electrical Characteristics
Symbol
Parameter
Conditions
Min
Typ
Max
Units
2.5
3.7
4.8
V
General Operating Conditions
VVIN
Supply Voltage
ISHUTDOWN
Shutdown
Current
AS3630 off, VBAT<3.7V, TAMB ≤ 50ºC,
ON=0
0.5
2.0
μA
ISTANDBY
Standby Current
AS3630 off, VBAT<3.7V, TAMB ≤ 50ºC,
ON=1
1.0
10
μA
IPRE_
Supercap
pre-charging
current
mode_setting = Supercap pre-charge
and charge_current =00b
CHARGE_
LOW_POWER
TAMB
Operating
Temperature
2
-30
25
μA
85
ºC
10
V
DCDC1/2 Step Up Converter
VDCDC
DCDC Boost
output Voltage
(pin VDCDC)
DCDC1 (LDCDC1) and/or DCDC2
(LDCDC2) is in operation
η
Efficiency
DCDC1 (LDCDC1) or DCDC2 (LDCDC2)
fCLK
Operating
Frequency
All internal timings are derived from
this oscillator
max_duty
DCDC1/2
maximum duty
cycle
84
%
RSW_P1
DCDC Switch
SW1 - VDCDC
100
mΩ
RSW_N1
DCDC Switch
SW1 - GND
100
mΩ
RSW_P2
DCDC Switch
SW2 - VDCDC
70
mΩ
RSW_N2
DCDC Switch
SW2 - GND
100
mΩ
DCDC
AS3630 – 8
90
-10%
4.0
%
+10%
MHz
8A Supercap Flash Driver
Symbol
Parameter
Conditions
Min
Typ
Max
Units
0
4.469
4.57
4.671
V
1
4.557
4.66
4.763
V
2
4.646
4.75
4.855
V
3
4.724
4.83
4.936
V
4
4.820
4.93
5.036
V
5
4.900
5.01
5.12
V
6
4.995
5.11
5.219
V
7
5.082
5.2
5.31
V
8
5.170
5.29
5.402
V
9
5.258
5.38
5.494
V
Ah
5.345
5.47
5.585
V
Bh
5.433
5.56
5.677
V
Ch
5.526
5.65
5.774
V
Dh
5.616
5.74
5.868
V
Eh
5.704
5.83
5.96
V
Fh
5.793
5.92
6.053
V
charge_current
=00b, low
quiescent
current mode
100
200
300
01b
380
500
650
10b
570
750
975
11b
760
1000
1300
Supercap Charger / Discharge
VSUPERCAP_
EOC
1
ISUPERCAP_
CHARGE
IKEEP_
CHARGE
RDIS_
CHARGE
End of charge
voltage for
Supercap
Pre-charging
current of
Supercap2
Programmable in
90mV steps by
register
end_of_charge_vo
ltage above 5.5V
max. 60000s
during lifetime of
AS3630
Pre-charging and
transition (to
charge) of
Supercap - see
Supercap
Charging/Discharg
e/Pre-charge to
VIN ; final charging
to VSUPERCAP_EOC is
controlled by
coil1_peak
Keeping Supercap
charged current
During torch, charge or PWM
operation keep VSUPERCAP charged
if keep_sc_charged =1
Discharge
resistance for
VSUPERCAP
mode_setting = 001b / shutdown
and discharge Supercap
8A Supercap Flash Driver
mA
10
mA
250*2
Ω
AS3630 – 9
Symbol
Parameter
Conditions
Min
Typ
Max
Units
LED Current Sources
ILED_OUT
LED_OUT Current
set by led_current
Limited lifetime max. 20000s,
mode_setting = flash operation;
current specified for each of the two
flash LEDs
10
(2x)
3000
mode_setting = torch operation
10
460
10
303.9
*
duty
cycle
-10
+10
mode_setting = PWM operation
duty cycle defined by led_out_pwm
Accuracy, ΔI
ILED_OUT_
RIPPLE
VFLASH_
COMP
IIND_OUT
VLED_OUT
LED_OUT ripple
current
ILED=2500mA, BW=20MHz
Flash current
source voltage
compliance
Minimum Voltage
between
VSUPERCAP and
LED_OUT to
generate the
programmed
current
(led_current)
Indicator Current
LED_OUTforward voltage
measured on pin
LED_OUT
200
led_current_ra
nge =00b or
01b
mA
%
mApp
0.4
V
10b
0.5
Range
1.0
8.0
mA
Accuracy, ΔI
-20
+20
%
led_current_range = 00b…10b
2.6
x2
4.4
x2
V
led_current_range = 11b (4A)
2.6
x2
4.325
x2
V
Set by ind_current
in 1mA steps
ADC
Resolution
10
‘000h
’
‘3FFh’
BAL, VIN, IND_OUT, PGND,
TXMASK/TORCH, STROBE, INT and ON
0.0
5.866
V
VSUPERCAP
0.0
6.666
V
NTC
0.0
2.2
V
VDCDC
0.0
11
V
ADC Code
Range
ADC input range;
channel selected
by ADC_channel
LED_OUT
12.1
Tjunc (AS3630 junction temperature, in ºC) =
round (((4 * ADC_D9-D2 + ADC_D1-D0) - 324) * -1.05042)
AS3630 – 10
bits
ºC
8A Supercap Flash Driver
Symbol
Averaging
Parameter
ADC internal
averaging filter
Conditions
Min
Max
Units
9.3
10.0
V
Range
500
3500
mA
Accuracy, ΔI
-10
+10
%
1000
6000
mA
-10
+10
%
Number of conversion per
measurement (averaged);
measurements can be started
immediately, at begin of flash and
end of flash - see ADC_convert
Typ
4
Protection and Fault Detection Functions
VVOUTMAX
VDCDC
overvoltage
protection
DCDC Converter Overvoltage
Protection
ILDCDC1
Current Limit for
coil LDCDC1 (Pin
SW1) measured at
75% PWM duty
cycle3
Set by coil1_peak
and
coil1_txmask_curr
_red during
TXMask
Range
Current Limit for
coil LDCDC2 (Pin
SW1) measured at
75% PWM duty
cycle3
Set by coil2_peak
VLEDSHORT
Flash LED short
circuit detection
voltage
Voltage measured on pin LED_OUT
monitored once the LED_OUT current
is at or above a minimum current “Short/Open LED Protection fault_led” on page 35
TOVTEMP
Overtemperature
Protection
TOVTEMP
Overtemperature
Hysteresis
ILDCDC2
Accuracy, ΔI
1.45
V
144
ºC
5
ºC
Junction temperature
HYST
Range
tFLASHTIMEO
UT
VUVLO
Flash Timeout
Timer
Undervoltage
Lockout
8A Supercap Flash Driver
Set by
flash_timeout
Accuracy, Δt
4
760
ms
-10%
-2ms
+10%
+2ms
Falling V VIN
2.3
2.4
2.5
V
Rising V VIN
VUVLO
+0.05
VUVLO
+0.1
VUVLO
+0.15
V
AS3630 – 11
Symbol
Parameter
Conditions
Min
Typ
Max
Units
Protection and Fault Detection Functions - NTC
0
INTC
VNTC_TH
NTC Current
Source
Threshold for
overtemperature
Adjustable by
NTC_current in
40μA steps,
V(NTC) ≤ 1.7V
off
1
34.4
40
45.6
μA
2
72
80
88
μA
3
110
120
130
μA
4
147
160
173
μA
5
184
200
216
μA
6
220
240
260
μA
7
257
280
303
μA
8
294
320
346
μA
9
331
360
389
μA
Ah
368
400
432
μA
Bh
404
440
476
μA
Ch
441
480
519
μA
Dh
478
520
562
μA
Eh
515
560
605
μA
Fh
552
600
648
μA
If ntc_on=1 and the voltage on NTC
drops below VNTC_TH, any flash/torch
or PWM operation of LED_OUT is
stopped
1.0
V
Digital Interface
VIH
High Level Input
Voltage
VIL
Low Level Input
Voltage
VOL
Low Level Output
voltage
Pin INT and SDAat 2mA
ILEAK
Leakage current
V VIN or GND
Pins SDA, SCL, ON
RPULLDOWN
Pulldown current
to GND
Pins
TXMASK/TORCH,
STROBE
tDEBTORCH
torch debounce
time
TXMASK/TORCH input in torch mode
AS3630 – 12
1.28
V VIN
V
0.0
0.5
V
0
0.2
V
-1.0
+1.0
μA
Pins SDA, SCL, ON, STROBE and
TXMASK/TORCH
1.8V on pad
35
kΩ
7.5
ms
8A Supercap Flash Driver
Symbol
tDEBTXMASK
Parameter
debounce timer
Conditions
Min
TXMASK/TORCH input in TXMask
mode - see “TXMASK” on page 28
Typ
Max
2.1
Units
μs
I²C Mode Timings (page 14 )
fSCLK
SCL Clock
Frequency
tBUF
Bus Free Time
Between a STOP
and START
Condition
1.3
μs
tHD:STA
Hold Time
(Repeated) START
Condition4
0.6
μs
tLOW
LOW Period of
SCL Clock
1.3
μs
tHIGH
HIGH Period of
SCL Clock
0.6
μs
tSU:STA
Setup Time for a
Repeated START
Condition
0.6
μs
tHD:DAT
Data Hold Time5
0
tSU:DAT
Data Setup Time6
100
tR
Rise Time of Both
SDA and SCL
Signals
20 +
0.1CB
300
ns
tF
Fall Time of Both
SDA and SCL
Signals
20 +
0.1CB
300
ns
tSU:STO
Setup Time for
STOP Condition
0.6
CB
Capacitive Load
for Each Bus Line
CI/O
I/O Capacitance
(SDA, SCL)
0
CB — total capacitance of one bus
line in pF
400
0.9
kHz
μs
μs
μs
400
pF
10
pF
1. In pre-charge the Supercap is always charged close to VVIN; therefore VSUPERCAP_EOC ≥ VVIN is possible
2. In order to reduce the total charging time of the Supercap, it is recommended to keep the Supercap pre-charged at VIN (can be enabled/disable by mode_setting)
3. Due to slope compensation of the current limit, the current limit changes with duty cycle
4. After this period, the first clock pulse is generated.
5. A device must internally provide a hold time of at least 300ns for the SDA signal (referred to the VIHMIN of the SCL signal) to bridge the undefined region of the falling edge of SCL.
6. A fast-mode device can be used in a standard-mode system, but the requirement tSU:DAT = to 250ns must then be met. This is automatically
the case if the device does not stretch the LOW period of the SCL signal. If such a device does stretch the LOW period of the SCL signal, it
must output the next data bit to the SDA line tR max + tSU:DAT = 1000 + 250 = 1250ns before the SCL line is released.
8A Supercap Flash Driver
AS3630 – 13
Timing Diagrams
Figure AS3630 – 7:
I2C Mode Timing Diagram
SDA
tBUF
tLOW
tR
tHD:STA
tF
SCLK
tHD:STA
tSU:STO
tSU:STA
tHD:DAT
tHIGH
tSU:DAT
REPEATED
STO START
All measurements are performed at V VIN=3.7V and TAMB=25°C.
LED = LXCL-LW07.
Typical Operating Characteristics
Figure AS3630 – 8:
Efficiency vs. Supply Voltage VIN for DCDC1
90
85
Efficiency (%)
80
75
70
65
60
55
coil1_peak=1.0A
50
coil1_peak=2.0A
coil1_peak=2.5A
45
coil1_peak=3.5A
40
3,0
3,5
4,0
4,5
5,0
5,5
Supply Voltage VIN [V]
Efficiency vs. Supply Voltage: Shows efficiency (POUT/PIN) of internal DCDC1 (VIN to VDCDC) vs. different supply
AS3630 – 14
8A Supercap Flash Driver
voltages.
Figure AS3630 – 9:
Efficiency vs. VSUPERCAP for DCDC2
90
85
Efficiency (%)
80
75
70
65
60
55
50
coil2_peak=3.14A
coil2_peak=4.57A
45
coil1_peak=6A
40
3,0
3,5
4,0
4,5
5,0
5,5
6,0
VSUPERCAP [V]
Efficiency vs. Supply Voltage: Shows efficiency (POUT/PIN) of internal DCDC2 (VSUPERCAP to VDCDC) vs. voltage on
VSUPERCAP while discharging from 6V down to 3V.
8A Supercap Flash Driver
AS3630 – 15
Figure AS3630 – 10:
Supercap Charging Cycle
VVSUPERCAP (1V/div)
VVOUT_DCDC (2V/div)
IVIN (500mA/div)
time (500ms/div)
Supercap charging cycle: Shows all phases for charging of the Supercap starting from Pre-charge to transitions
to charge until end of charge.
Figure AS3630 – 11:
Complete Flash Cycle
VVSUPERCAP (1V/div)
ILED_OUT (500mA/div)
IVVIN (500mA/div)
ISUPERCAP (2A/div)
time (2ms/div)
Complete flash cycle: Shows a complete LED flash cycle, flash time=16ms, ILED_OUT=3A, automatic re-charge
enabled at end of flash cycle.
AS3630 – 16
8A Supercap Flash Driver
Figure AS3630 – 12:
Startup of Flash Cycle
VVSUPERCAP (1V/div)
ILED_OUT (500mA/div)
IVVIN (500mA/div)
ISUPERCAP (2A/div)
time (40μs/div)
Startup flash cycle: Shows detailed (zoomed) of startup of a flash cycle, ILED_OUT=3A.
Figure AS3630 – 13:
Shutdown of Flash Cycle
ILED_OUT (500mA/div)
VLED_OUT (2V/div)
IVVIN (1A/div)
ISUPERCAP (1A/div)
time (50μs/div)
Shutdown flash cycle: Shows detailed (zoomed) of rampdown of a flash cycle, ILED_OUT=2.5A.
8A Supercap Flash Driver
AS3630 – 17
Figure AS3630 – 14:
Torch Cycle
VVDCDC_OUT (1V/div)
ILED_OUT (20mA/div)
IVVIN (500mA/div)
VVSUPERCAP (1V/div)
time (80μs/div)
Torch cycle: Shows a torch operation. To operate the torch no charging of the Supercap is required (see voltage
on VSUPERCAP), ILED_OUT=100mA.
Figure AS3630 – 15:
ILED_OUT Ripple Waveform
ILED_OUT (30mA/div, AC coupled)
time (100ns/div)
ILED_OUT ripple: Current ripple measured on ILED during flash with ILED_OUT=2A.
AS3630 – 18
8A Supercap Flash Driver
Figure AS3630 – 16:
Open LED Detection Waveform
VVDCDC_OUT (2V/div)
VLED_OUT (2V/div)
ILED_OUT (100mA/div)
time (400μs/div)
Open LED detection: Detailed measurement for detection of an open LED (LED disconnected) in torch mode.
Figure AS3630 – 17:
Short LED Detection Waveform
VVDCDC_OUT (1V/div)
VLED_OUT (1V/div)
ILED_OUT (50mA/div)
time (40μs/div)
Short LED detection: Detailed measurement for detection of a shorted LED (short during operation).
8A Supercap Flash Driver
AS3630 – 19
Figure AS3630 – 18:
Switching Waveform
VSW1 (3V/div)
VSW1 (2V/div)
ILDCDC1 (200mA/div ac
coupled)
time (320ns/div)
Switching waveform: Detailed measurement of the DCDC converters in operation during flash.
AS3630 – 20
8A Supercap Flash Driver
Detailed Descriptions
The AS3630 is a highly efficient dual DCDC Supercap charger
charging and balancing the Supercap and operating a LED flash
at up to 8A current.
The principle of operation of a AS3630 is as follows:
1. Charge the Supercap on VSUPERCAP to e.g. 5.5V - see
Supercap Charging/Discharge/Pre-charge to VIN
2. Torch (or PWM) operation of the LED does not depend
on a charge Supercap - see “Torch/PWM Operation” on
page 25.
3. Use DCDC1 to step up from VIN to VDCDC to source one
part of the LED_OUT current; in parallel use DCDC2 to
step up from -VSUPERCAP to VDCDC to source the
remaining part of the flash current - see Flash Operation.
Using this approach a very high current flash operation can be
performed using considerable low current from the battery
(usually batteries have a defined strict current limit, so the full
flash current cannot be supplied directly from the battery only).
Supercap Charging/Discharge/Pre-charge to VIN
The charging of the Supercap is performed in following steps:
• Pre-Charge - (see Figure below): Charge the Supercap
close to VIN - initiated by setting mode_setting = Supercap
pre-charge 1, 2:
The switch between SW1 and VDCDC is closed and ICHARGE
(set by charge_current) is used to control the charging
current. Use charge_current=00b for a special low power
mode only consuming I PRE_CHARGE_LOW_POWER.
1. This mode is usually used during standby of the system - the Supercap is kept at VIN; this will reduce the charging time, when the
camera is operated and the Supercap has to be charged to its final end of charge voltage (e.g. 5.5V)
2. In pre-charge the Supercap is always charged close to VVIN; therefore VSUPERCAP_EOC ≥ VVIN
8A Supercap Flash Driver
AS3630 – 21
Figure AS3630 – 19:
Supercap Pre-charging
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0
0
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1
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2
-32
20
• Transition3 between pre-charge -> charge: Once the
voltage on VSUPERCAP is close to V VIN and mode_setting
= “Supercap charge”, the DCDC1 converter is started and
the current source ICHARGE between VDCDC and
VSUPERCAP is used to finally charge VSUPERCAP to V VIN
3. To avoid a current peak at VIN if the VSUPERCAP is connected to VIN, but its voltage is still below VIN
AS3630 – 22
8A Supercap Flash Driver
Figure AS3630 – 20:
Supercap Charging
3
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0
0
0
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2
-32
20
• Charging - (see Figure above): Once the voltage on
VSUPERCAP ≥ VIN and mode_setting = “Supercap charge”,
the main charging can start: The DCCD1 converter is
operated and the switch between VDCDC and SW2 is closed.
The charging current in this phase is defined by the LDCDC1
peak current limit (programmed by coil1_peak).
Once the voltage on VSUPERCAP reaches
end_of_charge_voltage4, the peak current through L DCDC1
is reduced to 500mA. Charging is finished when the
voltage on VSUPERCAP again reaches
end_of_charge_voltage. Then the flash status_eoc is set and
if enabled by status_eoc_mask, INT is pulled low.
If keep_sc_charged=1, AS3630 will continuously check the
voltage on VSUPERCAP if it drops below
end_of_charge_voltage and automatically recharge the
Supercap with 5mA.
• Keep charge: Even in torch or PWM operation 5 of the LED
connected to LED_OUT the charge on VSUPERCAP can be
maintained by setting keep_sc_charged=1. Then the
current source I KEEP_CHARGE will be used to charger
VSUPERCAP from VDCDC (without exceeding
end_of_charge_voltage).
4. In pre-charge the Supercap is always charged close to VVIN; therefore VSUPERCAP_EOC ≥ VVIN
5. In these modes DCDC2 is not used as LED_OUT can be driven directly with DCDC1 from VIN.
8A Supercap Flash Driver
AS3630 – 23
• Shutdown: Setting mode_setting=”shutdown or external
torch mode (leave Supercap charged)” will keep the
Supercap charged and disables the balancing circuit.It can
be forced on if bal_force_on is set. If the voltage voltage
on VDCDC is above 5.35V, the Supercap will be discharged
until VDCDC is below 5.3V before shutdown mode is
entered.
• Shutdown and Discharge: Setting
mode_setting=”shutdown and discharge Supercap” will
slowly discharge the Supercap through RDIS_CHARGE 6 .
• Pre-Charge after Charge or Flash: Setting
mode_setting=”pre charge Supercap (to VIN)” will
discharge the Supercap to approximately V VIN-0.3V by
using RDIS_CHARGE. Afterwards the Supercap is charged
to V VIN as shown in Figure 19.
Note: If the Supercap is charged above 5.5V it will be discharged
to 5.5V even if the mode is set to “shutdown or external torch
mode (leave Supercap charged)” to protect the Supercap.
If during pre-charge, transition or charging operation, the
junction temperature exceed TOVTEMP, the operation is
temporarily stopped and automatically resumes, when the
junction temperature has dropped below TOVTEMP-TOVTEMPHYST.
The Supercap balancing circuit keeps both parts of the
Supercap at the same voltage level - see Balancing Circuit - Pin
BAL.
6. Implemented by a resistor between VSUPERCAP and BAL and another resistor between BAL and GND.
AS3630 – 24
8A Supercap Flash Driver
Torch/PWM Operation
Due to its concept, a torch or PWM operation can be performed
without even charging the Supercap (this allows instantaneous
video light or torch light):
Figure AS3630 – 21:
Immediate Torch (=Video Light) or PWM Operation
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After setting mode_setting = “Torch” or “PWM Operation” 7 the
step-up DCDC1 converter is used to generate -VDCDC sufficiently
high enough to drive the I LED_OUT current (controlled by
led_current). If keep_sc_charged (page 51)=1, VSUPERCAP is
charged by the current source IKEEP_CHARGE (without exceeding
end_of_charge_voltage) to maintain the charge on the Supercap
during this operating mode.
7. In PWM operation the current source ILED_OUT is PWM modulated with a duty cycle set by led_out_pwm.
8A Supercap Flash Driver
AS3630 – 25
Flash Operation
Additionally the step up converter DCDC1 (from VIN using
LDCDC1), the step up converter DCDC2 (from Supercap using
LDCDC2) is used in parallel operating at high efficiency for the
flash operation. This allows to reduce the current for each of the
DCDC’s and therefore the size of the Supercap and/or current
required from battery:
Figure AS3630 – 22:
Flash DCDC1 and DCDC2 Parallel Operation to Reduce Current and Size of Supercap
2
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The flash operation is enabled by mode_setting = “Flash” and
the timeout timer (register flash_timeout) defines the maximum
flash duration.
Note: If the voltage on VSUPERCAP drops below 2.55V, DCDC2
is automatically stopped (and the flash current is supplied by
DCDC1 only).
Once the flash is finished, the AS3630 will automatically select
the operating mode according to register mode_after_flash (see
page 51) shown in Figure 26:
AS3630 – 26
8A Supercap Flash Driver
Figure AS3630 – 23:
Automatically Selected Operating Mode After Flash
mode_after_flash
(see page 51)
mode_setting
updated to
00
000b
Shutdown of AS3630, but leave Supercap at the voltage
at the end of the flash
01
001b
Shutdown AS3630 and discharge Supercap
10
010b
Discharge the Supercap to approximately VVIN-0.3V by
using RDIS_CHARGE. Afterwards the Supercap is charged to
VVIN as shown in Figure 19 and kept at this voltage
11
011b
Supercap is automatically recharged to
end_of_charge_voltage
Mode selected after flash has been finished
DCDC1 / DCDC2 Operating Principle During Flash
In order to supply the required LED output current during flash
operation, DCDC1 (from VIN) and DCDC2 (from Supercap) are
used in parallel as shown in Figure 22.
Three different operating modes are used (automatically
selected by the AS3630):
1. DCCD1 alone can deliver the full flash current.
I DCDC1<coil1_peak, I DCDC2=0A
DCDC1 is regulated to deliver the flash LED current
alone; no current is used from DCDC2 or the Supercap.
2. DCDC1 and DCDC2 together deliver the flash current.
I DCDC1 hits coil1_peak, I DCDC2<coil2_peak
DCDC1 is operating in peak current limit (controlled by
coil1_peak) and DCDC2 is controlled to deliver the
remaining current for the LED. DCDC2 peak current is
below the setting coil2_peak.
3. DCDC1 and DCDC2 together cannot deliver the full flash
current.
I DCDC1 hits coil1_peak, I DCDC2 hits coil2_peak
In this operating mode both peak current settings
together (coil1_peak and coil2_peak) are not able to
deliver the programmed led_current. Therefore both
DCDCs are operating in coil current limit and the LED
current is the resulting sum of these two currents. If the
register bit curr_limit_curr_red is set, led_current is
ramped down 8 until DCDC2 leaves peak current limit
and operation continuous at mode 2. (DCDC1 and
DCDC2 together deliver the flash current) and
led_current_min is set to the reduced LED current.
4. If the voltage on VSUPERCAP drops below 2.4V, DCDC2
is disabled and the flash current drops to the current
supplied by DCDC1 only.
8. fault_current_reduced is set to indicate this condition.
8A Supercap Flash Driver
AS3630 – 27
Note: If DCDC1 shall not be used during flash (the whole current
has to be delivered by DCDC2 using the Supercap only, no
current from VIN) set the registers as follows:
txmask_torch_mode = 01b (TXMASK/TORCH is used as TXMask
input),
pull TXMASK/TORCH to ‘1’,
coil1_peak = 000b.
The AS3630 will then always operate in TXMask mode and
switch off DCDC1 (as coil1_peak = 000b).
Battery and Flash LED Current Reductions in Flash Mode
Current Reduction by VIN Measurements In Flash Mode
Due to the load of the flash driver and the ESR of the battery
(especially critical at low temperatures), the voltage on the
battery drops. If the voltage drops below the system reset
threshold, the system would reset. To prevent this condition the
AS3630 monitors the battery voltage and keeps it above
vin_low_v as follows:
During flash, if the voltage on VIN drops below the threshold
defined by vin_low_v, coil1_peak current is reduced thus
reducing the current from the battery and preventing a system
shutdown. Due to the unique regulation scheme (see DCDC1 /
DCDC2 Operating Principle During Flash) more current is
automatically used from the Supercap and therefore the flash
current is kept constant.
This function can be disabled by setting vin_low_v = 000b.
DCDC1 and DCDC2 in Current Limit
See DCDC1 / DCDC2 Operating Principle During Flash operating
mode 3.
TXMASK
The coil L DCDC1 current limit is usually defined by coil1_peak. If
this current is too high to allow parallel operation of another
high power load (e.g. the RF power amplifier) without
overloading of the battery, the TXMask function can be used.
Set txmask_torch_mode = 01b (TXMASK/TORCH is used as
TXMask input) and connect the enable line of the other high
power load to the AS3630 pin TXMASK/TORCH.
In the event of TXMASK/TORCH=1 during flash, the coil1_peak
current is instantaneously reduced by coil1_txmask_curr_red
steps (coding as for coil1_peak). If coil1_peak minus
coil1_txmask_curr_red steps would be negative DCDC1 is
switched off during TXMask.
Once TXMASK/TORCH=0, the coil peak current is ramped to the
previous programmed value of coil1_peak.
Continuous LED Current Ramp Down During Flash
If the register led_current_rampdown is set, the LED current
during flash is continuously ramped down. This has the benefit
of using the Supercap energy most efficiently.
AS3630 – 28
8A Supercap Flash Driver
Balancing Circuit - Pin BAL
Figure AS3630 – 24:
Balancing Circuit
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The internal balancing circuit (Figure 24) keeps the voltage
between VSUPERCAP-BAL to BAL-GND equal in order to avoid
overvoltage on one of the capacitors inside the Supercap. It is
powered from VSUPERCAP, therefore it can operate even if there
is no voltage on VIN.
The Supercap balancing circuit is active in pre-charge,
transition, charge, keep charge and discharge. It can be forced
on in flash and shutdown if bal_force_on is set.
8A Supercap Flash Driver
AS3630 – 29
Operating Mode and LED Currents
Currents and operating modes are selected according to the
following figure:
Figure AS3630 – 25:
Operating Mode and Current Settings
X
X
X
X
VIN supplied
Mode
All registers are
reset to their
default values
Standby
0
X
1
X
X
X
X
X
AS3630 – 30
txmask_torch_m
ode =10
txmask_torch_m
ode =10
010b
011b
Discharging
0
Shutdown
txmask_torch_m
ode not 10
000b,
001b
LED_OUT
output current
mode_setting
STROBE
TXMASK/TORCH
X
Operating Mode and Currents
Supercap
State
ON=0
ON=1; I²C commands are accepted on pins SCLK and SDA
Condition
No supply on VIN (0V)
X
ON, SCL, SDA
AS3630 Configuration
External torch
mode
Keep voltage as is
if mode_setting
=000b,
discharging if
mode_setting=00
1b
0mA
led_current1
limited to 460mA
Pre-charge
Pre-charge
Supercap to VIN
0mA
Charge
Charge Supercap
to
end_of_charge_v
oltage
0mA
8A Supercap Flash Driver
mode_setting
X
100b
Mode
Torch light mode
X
X
Use for indicator
with the main flash
LED or low current
PWM operation2
101b
0
X
Torch operation
sync to STROBE see Figure 32 on
page 35
110b
1
X
strobe_on = 0
Flash mode;
0>
1
strobe_on = 1
and
strobe_type = 0
flash duration
defined by
flash_timeout
0 or 14
ON=1; I²C commands are accepted on pins SCLK and SDA
PWM operation:
Flash mode;
111b
1
strobe_on = 1
and
strobe_type = 1
flash duration
defined by STROBE
input; timeout
defined by
flash_timeout
If
keep_sc_charged
=0 keep voltage
on Supercap as is;
if
keep_sc_charged
=1 charge
Supercap to
end_of_charge_v
oltage with
IKEEP_CHARGE Figure 21 on
page 25
Supercap is
discharged using
DCDC2 to
LED_OUT Figure 22 on
page 26
LED_OUT
output current
STROBE
X
Condition
Operating Mode and Currents
Supercap
State
TXMASK/TORCH
ON, SCL, SDA
AS3630 Configuration
led_current1
limited to 460mA
led_current3
limited to
303.9mA PWM
modulated by
led_out_pwm
(1/16...4/16 @
31.25kHz,
1/32, 3/32 @
15.625kHz)
0mA
led_current1
limited to 931mA
led_current for
flash duration
mode selected
after flash: see
Figure 23 on
page 27
1. If led_current_range=10 will use led_current_range=00.
2. The low current mode is a general purpose PWM mode to drive less current through the LED in average, but keep the actual pulsed current
in a range where the light output from the LED is still specified.
3. Will use led_current_range=00.
4. If txmask_torch_mode=01b then the DCDC1 peak coil current is changed depending on input TXMASK/TORCH - see section “TXMASK” on
page 28
8A Supercap Flash Driver
AS3630 – 31
Current Ranges
Depending on operating mode (mode_setting (see page 51)) the
current settings according to Figure 26 are possible9 :
Figure AS3630 – 26:
LED Current Selections
led_current_range
External Torch
Mode or Torch
Mode
PWM Operation
Flash
Operation
Torch operation
sync to STROBE
00
(10-2500mA range)
Ok, but limited to
460mA
Ok, but limited to
303.9mA
Ok
Ok, but limited to
931mA
01
(10-250mA range)
Ok
Will use 00 range
(10-303.9mA)
Ok
Ok
Will use 00 range
(10mA - 460mA)
Will use 00 range
(10-303.9mA)
Ok
Will use 00 range
(10mA - 931mA)
10
(2500-3000mA range)
SOFTSTART / Soft Ramp Down
During startup and ramp down the LED current is smoothly
ramped up and ramped down. Additionally the DCDC converter
on VIN has a startup mechanism to minimize or eliminate
battery input current overshoots.
Indicator Blinking Function
Setting ind_on=1 enabled the indicator current source on pin
IND_OUT. If ind_blink_delay=00 or ind_blink_on_time= 00, the
current source is constantly enabled with a current defined by
ind_current. All other conditions enable the indicator blinking
feature as shown in Figure 27 controlled by ind_blink_on_time,
ind_rampup_smooth, ind_rampdown_smooth, ind_blink_delay
and ind_current. Smooth current rampup and rampdown is
done using PWM modulation.
9. The LED current is limited by hardware to protect the LEDs under any condition.
AS3630 – 32
8A Supercap Flash Driver
Figure AS3630 – 27:
Indicator Blinking Function Waveform
Flash Strobe and Torch Sync to STROBE Timings
The timings are defined as follows:
1. Flash duration defined by register flash_timeout and
flash is started immediately when this mode is selected
by the I²C command (see Figure 28):
set strobe_on = 0, start the flash by setting mode_setting
= 111b
2. Flash duration defined by register flash_timeout and
flash started with a rising edge on pin STROBE (see
Figure 29):
set strobe_on = 1, strobe_type = 0 and setting
mode_setting = 111b
3. Flash start and timing defined by the pin STROBE; the
flash duration is limited by the timeout timer defined by
flash_timeout (see Figure 30 and Figure 31):
set strobe_on = 1, strobe_type = 1 and setting
mode_setting = 111b
4. Torch operation synchronized to pin STROBE; the
current is limited according to Figure 26:
setting mode_setting = 110b
Figure AS3630 – 28:
AS3630 Flash Duration Defined by flash_timeout without Using STROBE Input
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8A Supercap Flash Driver
AS3630 – 33
Figure AS3630 – 29:
AS3630 Flash Duration Defined by flash_timeout, Starting Flash with STROBE Rising Edge
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Figure AS3630 – 30:
AS3630 Flash Duration and Start Defined by STROBE, Limited by flash_timeout; Timer Not Expired
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Figure AS3630 – 31:
AS3630 Flash Duration and Start Defined by STROBE, Limited by flash_timeout; Timer Expired
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AS3630 – 34
8A Supercap Flash Driver
Figure AS3630 – 32:
AS3630 Torch Operation with Duration Synchronized to STROBE Input
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Protection, Status, NTC and Fault Detection
Supercap End of Charge Detection - status_eoc
Charging of the Supercap is performed as described in
Figure 20. Once charging is finished the register status_eoc is
set.
ADC End of Conversion - status_adc_eoc
Once the ADC conversion is finished, status_eoc is set - see
“ADC” on page 38.
Short/Open LED Protection - fault_led
After the startup of the LED_OUT current source, the voltage
on LED_OUT is continuously monitored and compared against
V LEDSHORT after the LED current has reached a minimum current
depending on led_current_range (see page 47) - see the figure
below:
Figure AS3630 – 33:
Short LED Detection Minimum Current
led_current_range
Short LED Detected Above
00
(10-2500mA range)
>29.4mA
01
(10-250mA range)
>20.58mA
10
(3000mA range)
>23.53mA
11
(4000mA range)
Disabled
If the voltage on LED_OUT stays below V LEDSHORT, a shorted LED
is detected.
8A Supercap Flash Driver
AS3630 – 35
If the voltage on VDCDC reaches V VOUTMAX and the voltage across
the current source between VDCDC and LED_OUT is below
V FLASH_COMP an open LED is detected.
If an open or shorted LED is detected, bit fault_led is set. The
DCDCs and current sinks are disabled and the Supercap is
discharged by setting mode_setting=001b. In external torch
mode, the register txmask_torch_mode is reset.
Note: Short/open LED detection is disabled in PWM operating
mode (mode_setting=101b). The voltage on VDCDC will
nevertheless never exceed V VOUTMAX.
AS3630 DIE Overtemperature Detected - fault_overtemp
The junction temperature of the AS3630 is continuously
monitored. If the temperature exceeds TOVTEMP, the DCDCs are
stopped, the current sources are disabled (instantaneous) and
the bit fault_overtemp is set (but the operating mode
mode_setting is not changed). The driver is automatically
re-enabled once the junction temperature drops below
TOVTEMP-TOVTEMPHYST.
Note: If an overtemperature is detected in Supercap pre-charge,
transition or charge mode, charging is temporarily disabled
until the temperature drops, but the register bit fault_overtemp
is not set.
Timeout Fault - fault_timeout
If the flash is started a timeout timer is started in parallel. If the
flash duration defined by the STROBE input (strobe_on=1 and
strobe_type=1, see Figure 31) exceeds tFLASHTIMEOUT
(adjustable by register flash_timeout), the DCDCs are stopped
and the flash current source (on pin LED_OUT) is disabled
(ramping down) and fault_timeout is set.
If the flash duration is defined by the timeout timer itself
(strobe_on = 0, see Figure 28), the register fault_timeout is not
set after the flash has been finished.
AS3630 will automatically select the operating mode according
to register mode_after_flash shown in Figure 26.
Supercap Short Detected - fault_sc_short
In all operating modes except shutdown (mode_setting not
000b or 001b) once VSUPERCAP is above 2.4V both internal
capacitors of the Supercap (VSUPERCAP-BAL and BAL-GND) are
monitored if they are shorted. If any of them is shorted10,
charging is stopped and the Supercap is discharged by setting
mode_setting=001b andfault_sc_short is set.
10. VSUPERCAP-BAL is compared with typ. 950mV, BAL-GND is compared with typ. 700mV.
AS3630 – 36
8A Supercap Flash Driver
NTC - Flash LED Overtemperature Protection - fault_ntc
Figure AS3630 – 34:
NTC Internal circuit
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The NTC input can be used to monitor the flash LED temperature
if ntc_on=1. A internal current source controlled by NTC_current
sources a current on pin NTC - see Figure 34. If the voltage on
pin NTC drops below VNTC_TH, fault_ntc is set, the DCDCs are
stopped and the flash current source (on pin LED_OUT) is
disabled (instantaneous) by setting mode_setting depending
on register mode_after_flash. If mode_after_flash=001b then
mode_setting=001b (shutdown and discharge Supercap). All
other settings of mode_after_flash result in mode_setting=000b
(shutdown).
As the external NTC cannot measure the LED temperature in
real time during a short high current flash pulse (the duration
from heating up of the LED until the NTC recognizes a too hot
LED is usually too long), it is advisable to measure the LED
temperature before the flash pulse (with the ADC and
NTC_current) and judge how much current can be driven
through the LED (to be estimated depending on LED heat sink
and is usually specified by the LED manufacturer).
LED Current Reduction Triggered - fault_current_reduced
If during flash the LED current has been reduced (for conditions
when this can occur see DCDC1 / DCDC2 Operating Principle
During Flash operating mode 3.), the register bit
fault_current_reduced is set for indication and lled_current_min
is set to the reduced LED current.
The operating mode is not changed and the DCDCs and current
source continue operation.
8A Supercap Flash Driver
AS3630 – 37
Supply Undervoltage Protection
If the voltage on the pin VIN (=battery voltage) is or falls below
V UVLO, the AS3630 is kept in shutdown state and all registers are
set to their default state.
Interrupt Output
INT is an open drain, active low output. The internal circuit to
control this pin is shown in Figure 35.
Figure AS3630 – 35:
Interrupts Processing
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Once an interrupt event occurs (e.g. end of charge of Supercap;
detailed description of interrupt events in “AS3630 Torch
Operation with Duration Synchronized to STROBE Input ” on
page 35, the interrupt flip flop is set (register status_eoc=1). If
the interrupt mask is high (register status_eoc_mask=1), the
output INT is pulled to low signalizing an interrupt condition.
All 8 interrupt flip flops are automatically cleared upon readout
of register Fault / Status.
ADC
The ADC is programmed by setting the ADC channel in register
ADC_channel (page 52) and the ADC conversion is performed
after setting ADC_convert (page 52).
The actual timing when the ADC conversion is started / finished
is programmed with ADC_convert as shown in Figure 36:
AS3630 – 38
8A Supercap Flash Driver
Figure AS3630 – 36:
ADC Timings
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Once the conversion is finished ADC_convert returns to 00b,
status_adc_eoc is set, and the result data is available from
register 4 * ADC_D9-D2 + ADC_D1-D0.
Note: The ADC input ranges and gains are described in Figure 6
subsection ADC.
I²C Mode Serial Data Bus
The AS3630 supports the I²C bus protocol. A device that sends
data onto the bus is defined as a transmitter and a device
receiving data as a receiver. The device that controls the
message is called a master. The devices that are controlled by
the master are referred to as slaves. A master device that
generates the serial clock (SCL), controls the bus access, and
generates the START and STOP conditions must control the bus.
The AS3630 operates as a slave on the I²C bus. Within the bus
specifications a standard mode (100kHz maximum clock rate)
and a fast mode (400kHz maximum clock rate) are defined. The
AS3630 works in both modes. Connections to the bus are made
through the open-drain I/O lines SDA and SCL.
The following bus protocol has been defined (Figure 37):
• Data transfer may be initiated only when the bus is not
busy.
• During data transfer, the data line must remain stable
whenever the clock line is HIGH. Changes in the data line
while the clock line is HIGH are interpreted as control
signals.
Accordingly, the following bus conditions have been defined:
Bus Not Busy
Both data and clock lines remain HIGH.
8A Supercap Flash Driver
AS3630 – 39
Start Data Transfer
A change in the state of the data line, from HIGH to LOW, while
the clock is HIGH, defines a START condition.
Stop Data Transfer
A change in the state of the data line, from LOW to HIGH, while
the clock line is HIGH, defines the STOP condition.
Data Valid
The state of the data line represents valid data when, after a
START condition, the data line is stable for the duration of the
HIGH period of the clock signal. The data on the line must be
changed during the LOW period of the clock signal. There is one
clock pulse per bit of data.
Each data transfer is initiated with a START condition and
terminated with a STOP condition. The number of data bytes
transferred between START and STOP conditions are not
limited, and are determined by the master device. The
information is transferred byte-wise and each receiver
acknowledges with a ninth bit.
Acknowledge
Each receiving device, when addressed, is obliged to generate
an acknowledge after the reception of each byte. The master
device must generate an extra clock pulse that is associated
with this acknowledge bit.
A device that acknowledges must pull down the SDA line during
the acknowledge clock pulse in such a way that the SDA line is
stable LOW during the HIGH period of the acknowledge-related
clock pulse. Of course, setup and hold times must be taken into
account. A master must signal an end of data to the slave by not
generating an acknowledge bit on the last byte that has been
clocked out of the slave. In this case, the slave must leave the
data line HIGH to enable the master to generate the STOP
condition.
AS3630 – 40
8A Supercap Flash Driver
Figure AS3630 – 37:
Data Transfer on I²C Serial Bus
SDA
MSB
7 bit SLAVE
ADDRESS
R/W
DIRECTION
ACKNOWLEDGEMENT SIGNAL FROM
RECEIVER
ACKNOWLEDGEMENT SIGNAL FROM
RECEIVER
SCLK
1
2
6
7
8
9
1
2
3-7
8
9
ACK
START
CONDITION
REPEATED IF
MORE BYTES
ARE TRANS-
STOP CONDITION
OR REPEATED
START CONDI-
Depending upon the state of the R/W bit, two types of data
transfer are possible:
1. Data transfer from a master transmitter to a slave
receiver. The first byte transmitted by the master is the
slave address. Next follows a number of data bytes. The
slave returns an acknowledge bit after each received
byte. Data is transferred with the most significant bit
(MSB) first.
2. Data transfer from a slave transmitter to a master
receiver. The master transmits the first byte (the slave
address). The slave then returns an acknowledge bit,
followed by the slave transmitting a number of data
bytes. The master returns an acknowledge bit after all
received bytes other than the last byte. At the end of the
last received byte, a “not acknowledge” is returned. The
master device generates all of the serial clock pulses and
the START and STOP conditions. A transfer is ended with
a STOP condition or with a repeated START condition.
Since a repeated START condition is also the beginning
of the next serial transfer, the bus is not released. Data
is transferred with the most significant bit (MSB) first.
The AS3630 can operate in the following two modes:
1. Slave Receiver Mode (Write Mode): Serial data and
clock are received through SDA and SCLK. After each
byte is received an acknowledge bit is transmitted.
START and STOP conditions are recognized as the
beginning and end of a serial transfer. Address
recognition is performed by hardware after reception of
the slave address and direction bit (see Figure 38). The
slave address byte is the first byte received after the
master generates the START condition. The slave
address byte contains the 7-bit AS3630 address, which
is shown in Figure 42, followed by the direction bit
(R/W), which, for a write, is 0. 11 After receiving and
decoding the slave address byte the device outputs an
acknowledge on the SDA line. After the AS3630
8A Supercap Flash Driver
AS3630 – 41
acknowledges the slave address + write bit, the master
transmits a register address to the AS3630. This sets the
register pointer on the AS3630. The master may then
transmit zero or more bytes of data, with the AS3630
acknowledging each byte received. The address pointer
will increment after each data byte is transferred. The
master generates a STOP condition to terminate the
data write.
2. Slave Transmitter Mode (Read Mode): The first byte is
received and handled as in the slave receiver mode.
However, in this mode, the direction bit indicates that
the transfer direction is reversed. Serial data is
transmitted on SDA by the AS3630 while the serial clock
is input on SCLK. START and STOP conditions are
recognized as the beginning and end of a serial transfer
(Figure 39 and Figure 40). The slave address byte is the
first byte received after the master generates a START
condition. The slave address byte contains the 7-bit
AS3630 address, which is shown in Figure 42, followed
by the direction bit (R/W), which, for a read, is 1.12 After
receiving and decoding the slave address byte the
device outputs an acknowledge on the SDA line. The
AS3630 then begins to transmit data starting with the
register address pointed to by the register pointer. If the
register pointer is not written to before the initiation of
a read mode the first address that is read is the last one
stored in the register pointer. The AS3630 must receive
a “not acknowledge” to end a read.
<Slave Address>
S
Figure 42
<RW>
Figure AS3630 – 38:
Data Write - Slave Receiver Mode
0
A
<Word Address (n)>
<Data(n)>
XXXXXXXX
XXXXXXXX
A
S - Start
A - Acknowledge (ACK)
P - Stop
<Data(n+X)>
<Data(n+1)>
A
XXXXXXXX
A
XXXXXXXX
A
P
Data Transferred
(X + 1 Bytes + Acknowledge)
11. The address for writing to the AS3630 is shown in Figure 42
12. The address for read mode from the AS3630 is shown in Figure 42
AS3630 – 42
8A Supercap Flash Driver
<Slave Address>
S
<RW>
Figure AS3630 – 39:
Data Read (from Current Pointer Location) - Slave Transmitter Mode
Figure 42
1
<Data(n+1)>
<Data(n)>
A
XXXXXXXX
A
XXXXXXXX
A
S - Start
A - Acknowledge (ACK)
P - Stop
NA - Not Acknowledge (NACK)
<Data(n+X)>
<Data(n+2)>
XXXXXXXX
A
XXXXXXXX
NA
P
Data Transferred
(X + 1 Bytes + Acknowledge)
Note: Last data byte is followed by a NACK
S
Figure 42
0
A
XXXXXXXX
A
XXXXXXXX
S - Start
Sr - Repeated Start
A - Acknowledge (ACK)
P - Stop
NA - Not Acknowledge (NACK)
A
<Slave Address>
Sr
Figure 42
A
XXXXXXXX
1
A
<Data(n+X)>
<Data(n+2)>
<Data(n+1)>
<Data(n)>
XXXXXXXX
<Word Address (n)>
<RW>
<RW>
Figure AS3630 – 40:
Data Read (Write Pointer, Then Read) - Slave Receive and Transmit
A
XXXXXXXX
NA
P
Data Transferred
(X + 1 Bytes + Acknowledge)
Note: Last data byte is followed by a NACK
I²C Address Selection
Note: It is required to read the register Fixed ID twice after
startup in order for the I²C address selection to identify the I²C
address used.
The AS3630 features two I²C slave addresses without having a
dedicated address selection pin. The selection of the I²C address
is done with the interconnection of AS3630 to the bus lines
shown in the figure below. The serial interface logic inside
AS3630 is able to distinguish between a direct I²C connection
to the master or a second option where data and clock line are
crossed. Therefore it is possible to address a maximum of two
AS3630 slaves on one I²C bus.
8A Supercap Flash Driver
AS3630 – 43
Figure AS3630 – 41:
I²C Address Selection Application Diagram
The I²C address use is defined according to the figure below:
Figure AS3630 – 42:
I²C Addresses for AS3630
7 bit I²C
address
8 bit I²C read
address
8 bit I²C write
address
1
(default; SCLK and SDA directly connected)
30h
60h
61h
2
(SCLK and SDA exchanged)
31h
62h
63h
Device Number
Figure 41 on page 44
8A Supercap Flash Driver
AS3630 – 44
Register Description
Figure AS3630 – 43:
Register Overview
Addr
00h
Name
<D7>
<D6>
<D5>
<D4>
<D3>
Fixed ID
fixed_id
Access
RO
Reset Value
<D2>
<D1>
<D0>
17h - fixed id (e.g. to check I²C communication)
Note: It is required to read the register Fixed ID twice after startup in order for the I²C address selection to identify the I²C address used.
Version
reserved
version
Access
RO
RO
Reset Value
NA
X
Don't use by application
Don't use by application
01h
8A Supercap Flash Driver
AS3630 – 45
Addr
Name
<D7>
<D6>
<D5>
<D4>
Current Set LED
<D3>
<D2>
<D1>
<D0>
led_current
Access
RW
Reset Value
15h (206mA)
LED Current pin LED_OUT; the range of this setting is defined by led_current_range
LSB is 9.8mA (2500mA/255) for led_current_range=00b
LSB is 980μA (250mA/255) for led_current_range=01b
LSB is 11.76mA (3000mA/255) for led_current_range=10b
led_current_range
02h
AS3630 – 46
led_current
00b
01b
10b
11b
00h
0mA
0mA
0mA
0mA
01h
9.8mA
02h
19.6mA
03h
29.4mA
Don’t use below 10mA (code
0Bh)
Don’t use
below
2506mA
(code D5h)
Don’t use
below
2996mA
(code BFh)
...
...
D5h
2088mA
209mA
2506mA
3341mA
...
...
...
...
...
FFh
2500mA
250mA
3000mA
4000mA
8A Supercap Flash Driver
Addr
Name
Boost/TXMask
Current
<D7>
<D6>
<D5>
<D4>
<D3>
<D2>
<D1>
<D0>
led_current_range
curr_limit_curr_r
ed
coil1_txmask_curr_red
txmask_torch_mode
Access
RW
RW
RW
RW
Reset Value
00b
0b
011b
00b
Reduce LDCDC1 current in steps of coil1_peak
currents during TXMask
(this is a delta value; e.g. -1 means one current
step reduction e.g. from 2.5A to 2.0A; -4
means four steps e.g. from 2.5A to 750mA. if
the reduction would result in a negative value,
DCDC1 is switch off during TXMask event)
000 … -1
001 … -2
010 … -3
011 … -4 - default value
100 … -5
101 … -6
Function of TXMASK/TORCH
pin
00 … no effect (default)
01 … txmask operation
mode (applies for flash
mode, mode_setting=111b)
10 … external torch mode
(applies for shutdown mode,
mode_setting=000b or
001b, max. led_current ≤
460mA)
11 … don't use
03h
Comment
Range setting for led_current
00...10-2500mA range
01...10-250mA range
10...2500-3000mA range
11...don’t use
use range “10” only for currents
above 2500mA
110 … -7
111 … -8
If set, reduce LED current if LDCDC1 and LDCDC2 currents are hit and current source ILED cannot drive
the output current.
Note: In flash mode LDCDC1 is usually operated in current limit.
8A Supercap Flash Driver
AS3630 – 47
Addr
Name
Coil and Charge
Current
<D7>
<D6>
<D4>
<D3>
<D2>
<D1>
charge_current
coil2_peak
coil1_peak
Access
RW
RW
RW
Reset Value
01b
010b
100b
Defines charging current of
Supercap for pre-charge and
‘transition’ (to charge);
afterwards coil1_peak defines
current
04h
Comment
00 … 200mA - low quiescent
current mode
01 … 500mA
10 ... 750mA
11 … 1000mA
AS3630 – 48
<D5>
LDCDC2 Coil Peak current limit
000 … don’t use
001 … don’t use
010 … 2.43A (default)
011 … 3.14A
100 … 3.86A
101 … 4.57A
110 … 5.29 A
111 … 6.0A
<D0>
LDCDC1 Coil Peak current limit
000 … don’t use
001 … 750mA
010 … 1A
011 … 1.5A
100 … 2A (default)
101 … 2.5A
110 … 3A
111 … 3.5A
8A Supercap Flash Driver
Addr
Name
Charge / Low
Voltage
<D7>
<D6>
<D5>
<D4>
<D3>
<D2>
<D1>
bal_force_on
end_of_charge_voltage
vin_low_v
Access
RW
RW
RW
Reset Value
0b
5h
5h
Define Supercap end of charge
Note: In pre-charge the Supercap is always charged close to VVIN;
therefore end_of_charge_voltage ≥ VVIN
05h
0h … 4.61V
1h … 4.7V
2h … 4.79V
3h … 4.88V
4h … 4.97V
5h … 5.06V (default)
6h … 5.15V
7h … 5.24V
8h … 5.33V
9h … 5.42V
Ah … 5.51V
Bh … 5.61V
Ch … 5.7V
Dh … 5.79V
Eh … 5.88V
Fh … 5.97V
<D0>
Reduce coil1_peak current if the VIN voltage
falls below vin_low_v 0h function is disabled
1h 3.0V
2h 3.07V
3h 3.14V
4h 3.22V
5h 3.3V - default
6h 3.38V
7h 3.47V
0 … balancing circuit is enabled according to the operating mode
1 … balancing circuit is always enabled
8A Supercap Flash Driver
AS3630 – 49
Addr
Name
Flash Timer
Access
Reset Value
<D7>
<D6>
<D5>
<D4>
<D3>
<D2>
ind_rampup_s
mooth
ind_rampdo
wn_smooth
flash_timeout
RW
RW
RW
1
1
0Fh
<D1>
<D0>
Flash timeout timer - define maximum flash time
4ms steps from 0…15h; 16ms steps from 16h to 63h
06h
Smooth
rampup during
indicator
blinking if
ind_on=1
0... none
1...smooth
(380ms)
AS3630 – 50
Smooth
rampdown
during
indicator
blinking if
ind_on=1
0... none
1...smooth
(380ms)
00h … 4ms
01h … 8ms
02h … 12ms
03h … 16ms
04h … 20ms
05h … 24ms
06h … 28ms
07h … 32ms
08h … 36ms
09h … 40ms
0Ah … 44ms
0Bh … 48ms
0Ch … 52ms
0Dh … 56ms
0Eh … 60ms
0Fh … 64ms
10h … 68ms
11h … 72ms
12h … 76ms
13h … 80ms
14h … 84ms
15h … 88ms
16h … 104ms
17h … 120ms
18h … 136ms
19h … 152ms
1Ah … 168ms
1Bh … 184ms
1Ch … 200ms
1Dh … 216ms
1Eh … 232ms
1Fh … 248ms
20h … 264ms
21h … 280ms
22h … 296ms
23h … 312ms
24h … 328ms
25h … 344ms
26h … 360ms
27h … 376ms
28h … 392ms
29h … 408ms
2Ah … 424ms
2Bh … 440ms
2Ch … 456ms
2Dh … 472ms
2Eh … 488ms
2Fh … 504ms
30h … 520ms
31h … 536ms
32h … 552ms
33h … 568ms
34h … 584ms
35h … 600ms
36h … 616ms
37h … 632ms
38h … 648ms
39h … 664ms
3Ah … 680ms
3Bh … 696ms
3Ch … 712ms
3Dh … 728ms
3Eh … 744ms
3Fh … 760ms
8A Supercap Flash Driver
Addr
Name
<D7>
<D6>
<D5>
<D4>
<D3>
<D2>
<D1>
<D0>
Control
ind_on
mode_after_flash
keep_sc_ch
arged
ntc_on
mode_setting
Access
RW
RW
RW
RW
RW
Reset Value
0b
11b
0b
0b
001b
Hardware
NTC
protection
of LED_OUT
0…off
1…on
000 ... shutdown or external torch mode (leave
Supercap charged)
001 ... shutdown or external torch mode and
discharge Supercap with RDIS_CHARGE - default
010 ... pre charge Supercap (to VIN)
011 ... charge Supercap
100 ... torch operation (wo/ Supercap) - max.
led_current ≤ 460mA
101 ... PWM Operation (main LED); max.
led_current ≤ 303.9mA; led_current_range is
set to 00b
110 ... torch operation sync to STROBE
(STROBE=1: LED on; STROBE=0: LED off ) max.
led_current ≤ 931mA
111 ... Flash Operation
07h
8A Supercap Flash Driver
Iindicator
current source
on IND_OUT
0 … off
1… on, (current
set by
ind_current)
Set the operating mode after
flash (see Figure 23 on page 27):
00... shutdown (leave Supercap
charged)
01... shutdown and discharge
Supercap
10... pre charge Supercap (to VIN)
11... charge Supercap
If set during
PWM,Torch
or Charge
operation
keep
Supercap
charged
with 10mA
current
AS3630 – 51
Addr
Name
<D7>
<D6>
strobe_on
strobe_type
ADC_convert
ADC_channel
Access
RW
RW
RW
RW
Reset Value
1b
1b
00b
0h
Strobe and ADC
control
08h
Enable STROBE
input
STROBE
input is
0 … edge
sensitive
1 … level
sensitive
<D5>
<D4>
Control ADC conversion register is automatically reset to
00 after the conversion is
finished
<D3>
<D2>
<D1>
<D0>
Select ADC channel for conversion
0h … VDCDC
1h … LED_OUT
2h ... Tjunc (DIE Junction temperature)
3h … VSUPERCAP
4h ... don’t use
5h ... BAL
6h … VIN
7h ... NTC
8h … IND_OUT
9h ... don’t use
Ah ... PGND.
Bh ... don’t use
Ch ... STROBE
Dh ... INT
Eh ... ON
Fh ... don’t use
00 … ADC shutdown (no conversion performed or end of conversion)
01 … start ADC conversion immediately
10 … do ADC conversion 1.5ms after current rampup (beginning of flash)
11 … do ADC conversion just before current rampdown (at end of flash; flash duration is extended
by 100μs)
AS3630 – 52
8A Supercap Flash Driver
Addr
Name
Fault / Status
Access
Reset Value
<D7>
<D6>
<D5>
<D4>
<D3>
<D2>
<D1>
<D0>
status_eoc
status_adc_e
oc
fault_led
fault_overte
mp
fault_timeo
ut
fault_sc_short
fault_ntc
fault_current
_reduced
SS_RC1
SS_RC
SS_RC
SS_RC
SS_RC
SS_RC
SS_RC
SS_RC
0b
0b
0b
0b
0b
0b
0b
0b
Shorted or open
LED (LED_OUT)
detected (see
page 35)
Overtemper
ature
(Tjunction)
triggered
(see
page 36)
Timeout has
triggered
(see
page 36)
Detect a
shorted
Supercap
(BAL-GND) or
(VSUPERCAPBAL) during
charging (see
page 36)
LED
Overtemper
ture
detection
hit
(monitored
by NTC) (see
page 36)
LED Current
has been
reduced and
register
09h
End Of
Supercap
Charge (see
page 35)
ADC end of
conversion
reached (see
page 35)
led_current_min reports min. led current during flash cycle (see page 37)
status_eoc_mas
k
status_adc_e
oc_mask
fault_led_mask
fault_overte
mp_mask
fault_timeo
ut_mask
fault_sc_short
_mask
fault_ntc_m
ask
fault_current
_reduced_m
ask
Access
RW
RW
RW
RW
RW
RW
RW
RW
Reset Value
0b
0b
0b
0b
0b
0b
0b
0b
If set,
overtemper
ature
(Tjunction)
triggers INT
If set
timeout
triggers INT
If set
fault_sc_short
triggers INT
If set
fault_ntc
triggers INT
If set
fault_current
_reduced
triggers INT
Interrupt Mask
0Ah
If set, end of
Supercap
charge triggers
INT
8A Supercap Flash Driver
If set ADC
end of
conversion
triggers INT
If set, a shorted
or open LED
(LED_OUT)
triggers INT
AS3630 – 53
Addr
Name
PWM and
Indicator
<D7>
<D6>
<D4>
<D3>
<D2>
<D1>
ind_blink_delay
ind_current
led_out_pwm
Access
RW
RW
RW
Reset Value
01b
000b
000b
Control indicator blinking
function delay between blinks if
ind_on=1
0Bh
00 ... continuously on (no
blinking)
01 ... 512ms
10 ... 1024ms
11 ... 2048ms
Minimum LED
Current
0Ch
<D5>
IND_OUT current setting if ind_on=1
000 … 1mA
001 … 2mA
010 … 3mA
011 … 4mA
100 … 5mA
101 … 6mA
110 … 7mA
111 … 8mA
<D0>
PWM modulate LED_OUT current if
mode_setting=PWM operation; automatically
uses led_current_range=00 (10mA...2500mA)
but limits current to 303.9mA (codes 00h...1Fh
for led_current)
000 1/32 PWM at 15.625kHz- subharmonic
oscillation are possible - not recommended to
use
001 don’t use - use 1/16 instead
010 3/32 PWM at 15.625kHz
011 don’t use - use 2/16 instead
100 1/16 PWM at 31.25kHz
101 2/16 PWM at 31.25kHz
110 3/16 PWM at 31.25kHz
111 4/16 PWM at 31.25kHz
led_current_min
Access
RO
Reset Value
00h
At the beginning of a flash pulse, led_current_min is set to led_current then it is reduced upon following condition: (coil1_peak hit
and coil2_peak hit and curr_limit_curr_red=1); led_current_min has the same coding used as led_current (the current reduction
happens in steps as the coding of led_current is done)
AS3630 – 54
8A Supercap Flash Driver
Addr
Name
<D7>
<D6>
ADC MSB
<D5>
<D4>
<D3>
<D2>
<D1>
<D0>
ADC_D9-D2
Access
RO
Reset Value
NA
0Dh
ADC MSB results bit 9 to bit 2
ADC LSB
led_current_rampdown
ADC_D1-D0
Access
RW
RO
Reset Value
00
NA
Automatically ramp-down of
LED current register led_current
during flash
00 ... no ramp-down
01 ...1LSB every 100μs
10 ...1LSB every 200μs
11 ...1LSB every 500μs
ADC LSB results bit 1 to bit 0
0Eh
8A Supercap Flash Driver
AS3630 – 55
Addr
Name
<D7>
<D6>
NTC
test6
skip_enable
ind_blink_on_time
NTC_current
Access
R/W
RW
RW
RW
0
1
10
8h
Reset Value
0Fh
Test bit - don’t
use
Allow
pulse-skip
operation or
force 4MHz
operation
0...4MHz
operation
1...pulse-skip
<D5>
<D4>
<D3>
Control indicator blinking
on-time if ind_on=1 (excluding
rampup/down)
00 ... 0ms (immediate
ramp-down after ramp-up)
01 ... 128ms
10 ... 256ms - default
11 ... 512ms
<D2>
<D1>
<D0>
Current through the NTC when overtemperature protection of
the LEDs (LED_OUT) is monitored
0h … off; use for an external drive of NTC
1h … 40μA
2h … 80μA
3h … 120μA
4h … 160μA
5h … 200μA
6h … 240μA
7h … 280μA
8h … 320μA - default
9h … 360μA
Ah … 400μA
Bh … 440μA
Ch … 480μA
Dh … 520μA
Eh … 560μA
Fh … 600μA
OTP1
OTP_data1
Access
RO
Reset Value
NA
10h
Data of OTP
AS3630 – 56
8A Supercap Flash Driver
Addr
Name
<D7>
<D6>
<D5>
<D4>
<D3>
OTP2
OTP_data2
Access
RO
Reset Value
NA
<D2>
<D1>
<D0>
11h
Data of OTP
OTP3
OTP_data3
Access
RO
Reset Value
NA
12h
Data of OTP
13h
OTP4
OTP_lock
OTP_data4
Access
RO
RO
Reset Value
NA
NA
Data of OTP
0 ... OTP is program-able (unlocked)
1... OTP is locked and no further programming of OTP is possible
1. SS_RC = automatically cleared upon readout
8A Supercap Flash Driver
AS3630 – 57
Register Map
Figure AS3630 – 44:
Register Map
Addr
Name
Default
00h
Fixed ID
17h
01h
Version
XXh
02h
Current Set
LED
15h
03h
Boost/TXMas
k Current
0Ch
led_current_range
04h
Coil and
Charge
Current
54h
charge_current
05h
Charge / Low
Voltage
2Dh
bal_force_on
06h
Flash Timer
CFh
ind_rampup_s
mooth
07h
Control
61h
ind_on
08h
Strobe and
ADC control
C0h
strobe_on
strobe_type
09h
Fault /
Status1
00h
status_eoc
status_adc_
eoc
AS3630 – 58
<D7>
<D6>
<D5>
<D4>
<D3>
<D2>
<D1>
<D0>
fixed_id
reserved
version
led_current
curr_limit_curr
_red
coil1_txmask_curr_red
txmask_torch_mode
coil2_peak
coil1_peak
end_of_charge_voltage
ind_rampdo
wn_smooth
vin_low_v
flash_timeout
mode_after_flash
keep_sc_ch
arged
ntc_on
ADC_convert
fault_led
fault_overt
emp
mode_setting
ADC_channel
fault_timeo
ut
fault_sc_shor
t
fault_ntc
fault_curren
t_reduced
8A Supercap Flash Driver
Addr
Name
Default
<D7>
<D6>
<D5>
<D4>
<D3>
<D2>
<D1>
<D0>
0Ah
Interrupt
Mask
00h
status_eoc_m
ask
status_adc_
eoc_mask
fault_led_mask
fault_overt
emp_mask
fault_timeo
ut_mask
fault_sc_shor
t_mask
fault_ntc_
mask
fault_curren
t_reduced_
mask
0Bh
PWM and
Indicator
40h
0Ch
Minimum
LED Current
NA
led_current_min
0Dh
ADC MSB
NA
ADC_D9-D2
0Eh
ADC LSB
0Xh
0Fh
NTC
68h
10h
OTP1
NA
OTP_data12
11h
OTP2
NA
OTP_data2
12h
OTP3
NA
OTP_data3
13h
OTP4
NA
ind_blink_delay
led_current_rampdown
test6
skip_enable
OTP_lock
Read-Only Register
R/W Register
ind_current
0
led_out_pwm
0
0
ind_blink_on_time
0
ADC_D1-D0
NTC_current
OTP_data4
if writing to read-only register is required, write ‘0’ to read-only positions
(e.g. ADC LSB)
1. The register Fault / Status is a read only register, which is automatically cleared after readout. Therefore only a single I²C access is required to poll the status of the AS3630.
2. If OTP data are fused in-circuit, expect a small yield loss.
8A Supercap Flash Driver
AS3630 – 59
Application Information
External Components
Supercap
The Supercap performance is critical for the performance of
AS3630. As the Supercap is affected by aging, the flash
performance has to be checked at end of life conditions.
Figure AS3630 – 45:
Recommended Supercap’s
Part
Number
C
ESR
Rated
Voltage
Peak
Rated1
Voltage
Match
ing2
Temp
Range3
Size
DME2Z5R5K43
4M3BT
430mF
±20%
50mΩ
5.5V
4.2V
<5%
-30ºC...
+70ºC
20.5x18.5
x3.2mm
DME2U5R5L35
4M3BT
350mF
±20%
60mΩ
5.5V
4.2V
<5%
-30ºC...
+70ºC
20.5x18.5
x3.0mm
DMF3R5R5L35
4M3DTA0
350mF
±20%
60mΩ
5.5V
4.2V
<5%
-30ºC...
+70ºC
21.0x14.0
x2.5mm
-20ºC...
+70ºC
26x44
x0.8mm
Manufact
urer
Murata
www.murat
a.com
TDK
EDLC082644-3
31-2F-11
330mF
80mΩ
5.5V
3.2V
www.tdkcomponent
s.com
1. Can be applied constantly
2. Difference of Capacitance of top capacitor (between VSUPERCAP/BAL) to capacitance of bottom capacitor (between BAL/GND).
3. Operating temperature range
AS3630 – 60
8A Supercap Flash Driver
LEDs
The LED with its optics and its performance are a key element
in a Supercap LED flash. Therefore use 2 high power LEDs with
lowest forward voltage.
Figure AS3630 – 46:
Recommended LEDs
Part
Number
Vf
@ 1A
Brightness
@ 1A
ILED
@ 25ºC
ILED peak
@ 25ºC
Size
CUW CFUP
3.5V
(max. 4.2V)
250-355lm
30mA-120
0mA
2500mA, t ≤
10ms,
duty=0.005
2x1.64x0.6
3mm, max
H 0.74mm
2.24x1.84x
0.75mm
CL-778
Manufacturer
Osram-OS
www.osram-os.com
Citizen Electronics
ce.citizen.co.jp/lighting
_led/en/index.html
Lumileds
LXCL-LW07
3000mA
www.philipslumileds.c
om
Input Capacitor C VIN
Low ESR input capacitors reduce input switching noise and
reduce the peak current drawn from the battery. Ceramic
capacitors are required for input decoupling and should be
located as close to the device as is practical.
Figure AS3630 – 47:
Recommended Input Capacitor
Part Number
C
TC Code
Related
Voltage
Size
GRM188R60J106ME47
10μ
>[email protected]
>[email protected]
X5R
6V3
0603
LMK107BBJ106MA
10μ
>[email protected]
X5R
6V3
0603
Manufacturer
Murata
www.murata.com
Taiyo Yuden
www.t-yuden.com
If a different input capacitor is chosen, ensure similar ESR value
and at least 3μF capacitance at the maximum input supply
voltage. Larger capacitor values (C) may be used without
limitations.
Optionally add a smaller capacitor in parallel to the input pin
VIN (e.g. Murata GRM155R61C104, >50nF @ 3V, 0402 size).
8A Supercap Flash Driver
AS3630 – 61
Output Capacitor C DCDC1 , C DCDC2
Low ESR capacitors should be used to minimize VDCDC ripple
and therefore current ripple on the LED. Multi-layer ceramic
capacitors are recommended since they have extremely low
ESR and are available in small footprints. The capacitor should
be located as close to the device as is practical.
X5R dielectric material is recommended due to their ability to
maintain capacitance over wide voltage and temperature
range.
Figure AS3630 – 48:
Recommended DCDCs Capacitor
Part Number
GRM219R61A106ME47
GRM219R61A106ME441
2 x C2012X5R1A106M2
C
TC Code
Related
Voltage
Size
X5R
10V
0805
(2.0x1.25x0.85mm
max 1mm height)
10V
2x0805
(2.0x1.25x0.85mm
max 0.95mm
height)
10μF ±20%
>[email protected]
10μF ±10%
>[email protected]
10μF ±20%
X5R
Manufacturer
Murata
www.murata.com
TDK
www.tdk.com
1. If TAMB<70ºC or higher output voltage ripple can be tolerated.
2. Use 2 in parallel for CDCDC1 and CDCDC2 to reach the required output capacitor of >4.2μF capacitance at 5V.
If a different output capacitor is chosen, ensure similar ESR
values and at least 4.2μF capacitance at 5V output voltage and
for CDCDC1 10V voltage rating, C DCDC2 6.3V voltage rating.
Inductor L DCDC1
LDCDC1 is used for charging of the Supercap, operate the LED in
torch and PWM operation and in parallel to L DCDC2 to power the
LED during flash. Due to the different durations of the operation
modes, different peak current limits apply (see Figure 49).
The fast switching frequency (4MHz) of the AS3649 allows for
the use of small SMDs for the external inductor. The saturation
current ISATURATION should be chosen to be above the
maximum value of ILDCCD1 13. The inductor should have very
low DC resistance (DCR) to reduce the I2R power losses - high
DCR values will reduce efficiency.
13. Can be adjusted in I²C mode with register coil1_peak
AS3630 – 62
8A Supercap Flash Driver
Figure AS3630 – 49:
Recommended Inductor
Part Number
L
max. coil1_peak
setting for
DCR
Other modes
Size
Flash
3.2x2.5x0.9mm
max 1.0mm
height
LQM32PN1R0MG0
1.0μH
>0.6μH @
3.0A
60mΩ
2.0A
3.0A
SPM3012T-1R0M
1.0μH
±20%
57mΩ
±10%
2.5A
3.0A
(3.5A2)
3.2x3x1.2
mm
height is max
CIG32W1R0MNE
1.0μH
>0.7μH @
2.7A
>0.6μH @
3.0A
60mΩ
±25%
2.0A
3.0A
3.2x2.5mm
max 1.0mm
height
CKP3225N1R0M
1.0μH
>0.6μH @
3.0A
<60mΩ
1.0A
3.0A3
3.2x2.5x0.9mm
max 1.0mm
height
MAMK2520T1R0M
1.0μH
>0.6μH@
2.75A
Manufacturer
1
Murata
www.murata.com
TDK
www.tdk.com
Samsung
Electro-Mechancs
www.sem.samsun
g.co.kr
Taiyo Yuden
www.t-yuden.com
45mΩ
2.5A
2.5A
2.5x2.0x1.2mm
height is max
1. Flash pattern: 200ms/3A, 200ms pause, 200ms/3A, 2s then repeat again (no limit on the number of total cycles)
Alternative pattern with 1000ms/1.6A, 200ms pause, 200ms/3A, 200ms pause, 200ms/3A, 2s then repeat again. (no limit on the number of
total cycles)
2. Check with coil supplier
3. Check with coil supplier for worst case flash pattern.
If a different inductor is chosen, ensure similar DCR values and
at least0.6μH inductance at ILDCCD1 set by coil1_peak.
Inductor L DCDC2
LDCDC2 is used in parallel to L DCDC1 to power the LED during
flash. The whole current from the Supercap flows through
LDCDC2 therefore a high power inductor is required.
The fast switching frequency (4MHz) of the AS3649 allows for
the use of small SMDs for the external inductor. The saturation
current ISATURATION should be chosen to be above the
maximum value of ILDCCD2 14. The inductor should have very
low DC resistance (DCR) to reduce the I2R power losses - high
DCR values will reduce efficiency
14. Can be adjusted in I²C mode with register coil2_peak
8A Supercap Flash Driver
AS3630 – 63
Figure AS3630 – 50:
Recommended Inductor
Part Number
L
MPI4040R2-1R0-R
1.0μH
>0.6μH @ 6.0A
DCR
25mΩ
max.
coil2_peak
setting
Size
6.0A
(max. value)
4.06x4.45x1
.5mm
height is
max
1
MPI4040R1-1R0-R
1.0μH
>0.6μH @ 6.0A
40mΩ
check with
coiltronics
4.06x4.45x1
.2mm
height is
max
XAL4020-102ME_
1.0μH
>0.6μH @ 6.0A
13.25mΩ
6.0A
(max. value)
4x4x2mm
max 2.1mm
height
XFL4020-102ME_
SPM4012T-1R0M
1.0μH
>0.6μH @
5.29A
1.0μH ± 20%
14.4mΩ
38mΩ
57mΩ
±10%
5.29A
4x4x2mm
max 2.1mm
height
4.57A
4.4x4.1x1.2
mm
height is
max
3.0A
(3.5A2)
3.2x3x1.2
mm
height is
max
SPM3012T-1R0M
1.0μH ± 20%
LQM32PN1R0MG0
1.0μH
>0.6μH @ 3.0A
60mΩ
3.0A3
3.2x2.5x0.9
mm
max 1.0mm
height
CIG32W1R0MNE
1.0μH
>0.7μH @ 2.7A
>0.6μH @ 3.0A
60mΩ
±25%
3.0A
3.2x2.5mm
max 1.0mm
height
CKP3225N1R0M
1.0μH
>0.6μH @ 3.0A
<60mΩ
3.0A4
3.2x2.5x0.9
mm
max 1.0mm
height
Manufacturer
Coiltronics (Cooper
Bussmann)
www.cooperbussmann.c
om
Coilcraft
www.coilcraft.com
TDK
www.tdk.com
Murata
www.murata.com
Samsung
Electro-Mechancs
www.sem.samsung.co.kr
Taiyo Yuden
www.t-yuden.com
1. Flash profile and max. TAMB to be checked with coil manufacturer.
2. Check with coil supplier
3. Flash pattern: 200ms/3A, 200ms pause, 200ms/3A, 2s then repeat again (no limit on the number of total cycles)
Alternative pattern with 1000ms/1.6A, 200ms pause, 200ms/3A, 200ms pause, 200ms/3A, 2s then repeat again. (no limit on the number of
total cycles)
4. Check with coil supplier for worst case flash pattern.
If a different inductor is chosen, ensure similar DCR values and
at least0.6μH inductance at ILDCCD2 set by coil2_peak.
AS3630 – 64
8A Supercap Flash Driver
Thermistor (NTC)
The NTC is used to protect the LED against overheating
(hardware protection inside the AS3649, which works without
any software - see “NTC - Flash LED Overtemperature Protection
- fault_ntc” on page 37.
The thermistor has to be thermally coupled to the LED (and
therefore as close as possible to the LED) and it shall not share
the same ground connection as the LED return ground (if they
share the same ground connection the high current through
the LED will offset the measurement of the NTC).
Figure AS3630 – 51:
Recommended Thermistors
Part Number
Resistance @ 25ºC
B-constant 25/50ºC
Size
NCP02WF104F05RH
100kΩ ±1%
4250k ±1%
01005 (inch)
NCP02XH103F05RH
10kΩ ±1%
3380k ±1%
01005 (inch)
NCP03WL224E05RL
220kΩ ± 3%
4485K ± 1%
0201 (inch)
NCP03WL104E05RL
100kΩ ± 3%
4485K ± 1%
NCP15WF104F03RC
100kΩ
NCP15WL683J03RC
68kΩ
NTCG104QH224HT
220kΩ ± 3%
4750k ± 3%
NTCG104EF104FT
100kΩ ± 1%
4250k ± 1%
Manufacturer
Murata
www.murata.com
0402 (inch)
1.0x0.5mm
NTCG104LH683JT
4550k ± 3%
TDK
www.tdk.com
68kΩ ± 5%
NTCG104BF683JT
4085k ± 1%
It is recommended to use 220kΩ resistance for a detection
threshold of 125ºC, 100kΩ for 110ºC and 68kΩ for 80ºC LED
temperature detection threshold.
8A Supercap Flash Driver
AS3630 – 65
The high speed operation requires proper layout for optimum
performance. Route the power traces first and try to minimize
the area and wire length.
PCB Layout Guideline
At the pin GND a single via (or more vias, which are closely
combined) connects to the common ground plane. This via(s)
will isolate the DCDC high frequency currents from the common
ground - see the ‘ground via’ in Figure 52.
Figure AS3630 – 52:
Layout Recommendation Using a 3225 Coil for LDCDC1 and LDCDC2
1
*
*+
, (&)&
*2%*
"'
"'
)"-./
#'" !/0"/
%&!"
!""
#$
Note:
If component placement rules allow, move all components close to the AS3630.
The NTC ground connection shall be separated from the main ground and directly connected to AGND (Ball A5).
The recommended PCB pad size for the AS3630 is 250μm.
AS3630 – 66
8A Supercap Flash Driver
Drive 4 LEDs
In order to drive 4 LEDs at a maximum current of up to 4x3A =
12A 15 using a single Supercap, two AS3630 can be used. The I²C
connections can be combined as the AS3630 supports two I²C
addresses (see “I²C Address Selection” on page 43). Use the
circuit shown in the figure below- to synchronize the flash
pulses use the STROBE input:
Figure AS3630 – 53:
Combining Two AS3630 Using a Single Supercap
1&77
-&Z7
17
2*#
!
!
2*#
!
!$
/"
3
#
!$
3
456
!
)*+
%&'(
3
&.
,(
!
!$
!
"-"
3
)0&1
,(&
(
$
171
$
"
!
3
)
3
1&77
17Z,1&77
-&
&.
,(
#
6
)
456
!
)*+
%&'(
!$
!
!$
/"
3
2*#
!
"-"
!
6
!$
)0&1
&&
&&
$
171
6
$
3
!3
)
755)
&1&&
77&Z!3
/&&'%&
3&&5
15. Will depend on the Supercap and LEDs VF which flash current / flash duration can be used.
8A Supercap Flash Driver
AS3630 – 67
Package Drawings and Markings
Figure AS3630 – 54:
25pin WL-CSP Marking
Notes:
1. Line 1 : ams AG logo
2. Line 2 : AS3630
3. Line 3 : <Code> (Encoded Datecode - 4 characters)
Figure AS3630 – 55:
25pin WL-CSP Package Dimensions
!"
#!$
%
&
%
"
"&
"%
"
"%
"%
"&
"
"
&
%
%
%
&
'
'
'&
'%
'
'%
'%
'&
'
'
&
*
(
(
(&
(%
(
(%
(%
(&
(
(
)
)
)&
)%
)
)%
)%
)&
)
)
Note:
AS3630 – 68
"
+&
The coplanarity of the balls is 40μm
8A Supercap Flash Driver
The devices are available as standard products as shown below.
Ordering Information
Figure AS3630 – 56:
Ordering Information
Ordering Code
Description
Delivery
AS3630-ZWLT
8A Supercap Flash Driver
with Torch and Indicator
Tape & Reel
Package
25-pin WL-CSP
5x5 balls 0.5mm pitch, 2.5x2.5x0.6mm size
RoHS compliant / Pb-Free
AS3630-ZWLT:
AS3630Z : Temperature Range: -30ºC - 85ºC
WL : Package: Wafer Level Chip Scale Package (WL-CSP)
T : Delivery Form: Tape & Reel
Note:
All products are RoHS compliant and ams green.
Buy our products or get free samples online at www.ams.com/ICdirect
Technical Support is available at www.ams.com/Technical-Support
For further information and requests, email us at [email protected]
(or) find your local distributor at www.ams.com/distributor
8A Supercap Flash Driver
AS3630 – 69
The PCB assembly should be instrumented and the reflow
oven’s process parameters established to ensure the solder
paste manufacturer’s reflow profile specification is met during
the assembly process. See Figure below.
Soldering Information
The maximum PCB temperature recommended by the supplier
must not be exceeded.
Figure AS3630 – 57:
Solder Reflow Profile
Profile Feature
Lead-free Assembly
Average ramp-up rate (Tsmax to TP)
3 °C/second max.
Preheat
• Temperature Min (Tsmin)
• Temperature Max (Tsmax)
• Time (tL)
150 °C
200 °C
60 – 120 seconds
Time maintained above:
• Temperature (TL)
• Time (tL)
217 °C
60 – 150 seconds
Peak/classification temperature (TP)
260 °C
Time within 5 °C of actual peak temperature (TP)
30 seconds
Ramp-down rate
6 °C/second max.
Time 25 °C to peak temperature
8 minutes max.
JEDEC standard Lead-free reflow profile: According to J-STD-020D.
Temperature [°C]
Figure AS3630 – 58:
Recommended Reflow Soldering Profile
tP
TP
Critical
Zone
TL to TP
Ramp
Up
TL
TL
Tsmax
Ramp Down
Tsmin
TL
25
AS3630 – 70
t 25°C to Peak Temperature
Time [s]
8A Supercap Flash Driver
RoHS Compliant and ams Green
Statement
The term RoHS compliant means that ams products fully comply
with current RoHS directive. Our semiconductor products do
not contain any chemicals for all 6 substance categories,
including the requirement that lead not exceed 0.1% by weight
in homogeneous materials. Where designed to be soldered at
high temperatures, RoHS compliant products are suitable for
use in specified lead-free processes. ams Green means RoHS
compliant and no Sb/Br). ams defines Green that additionally
to RoHS compliance our products are free of Bromine (Br) and
Antimony (Sb) based flame retardants (Br or Sb do not exceed
0.1% by weight in homogeneous material).
Important Information and Disclaimer The information
provided in this statement represents ams knowledge and
belief as of the date that it is provided. ams bases its knowledge
and belief on information provided by third parties, and makes
no representation or warranty as to the accuracy of such
information. Efforts are underway to better integrate
information from third parties. ams has taken and continues to
take reasonable steps to provide representative and accurate
information but may not have conducted destructive testing or
chemical analysis on incoming materials and chemicals. ams
and ams suppliers consider certain information to be
proprietary, and thus CAS numbers and other limited
information may not be available for release.
8A Supercap Flash Driver
AS3630 – 71
Copyrights
Copyright © 1997-2013, ams AG, Tobelbaderstrasse 30, 8141
Unterpremstaetten, Austria-Europe. Trademarks Registered ®.
All rights reserved. The material herein may not be reproduced,
adapted, merged, translated, stored, or used without the prior
written consent of the copyright owner.
Disclaimer
Devices sold by ams AG are covered by the warranty and patent
indemnification provisions appearing in its Term of Sale. ams
AG makes no warranty, express, statutory, implied, or by
description regarding the information set forth herein or
regarding the freedom of the described devices from patent
infringement. ams AG reserves the right to change
specifications and prices at any time and without notice.
Therefore, prior to designing this product into a system, it is
necessary to check with ams AG for current information. This
product is intended for use in normal commercial applications.
Applications requiring extended temperature range, unusual
environmental requirements, or high reliability applications,
such as military, medical life-support or life-sustaining
equipment are specifically not recommended without
additional processing by ams AG for each application. For
shipments of less than 100 parts the manufacturing flow might
show deviations from the standard production flow, such as test
flow or test location.
The information furnished here by ams AG is believed to be
correct and accurate. However, ams AG shall not be liable to
recipient or any third party for any damages, including but not
limited to personal injury, property damage, loss of profits, loss
of use, interruption of business or indirect, special, incidental
or consequential damages, of any kind, in connection with or
arising out of the furnishing, performance or use of the
technical data herein. No obligation or liability to recipient or
any third party shall arise or flow out of ams AG rendering of
technical or other services.
AS3630 – 72
8A Supercap Flash Driver