MAXIM MAX8830EWET

19-0782; Rev 0; 4/07
LED Light Management IC in
2.5mm x 2.5mm UCSP
Features
The MAX8830 light management IC integrates a 280mA
PWM DC-DC step-up converter, a 200mA white LED
camera flash current sink, and four programmable LED
current sinks. The internal 1MHz step-up converter features an internal switching MOSFET and synchronous
rectifier to improve efficiency and minimize external
component count. The camera flash output current and
maximum timer is programmable through I2C. Each LED
current is individually regulated to a programmable level
(from off to 10mA in 32 steps) and is completely independent of each other.
♦ Step-Up DC-DC Converter
280mA Guaranteed Output Current
Over 90% Efficiency
On-Chip FET and Synchronous Rectifier
Fixed 1MHz PWM Switching
Small 2.2µH to 10µH Inductor
I2C-Programmable VOUT (3.8V to 5.2V and Off in
16 Steps)
An I2C interface controls individual on/off of all outputs,
step-up output voltage setting, movie/flash current,
flash timer duration settings, and individual LED current
sink settings.
The MAX8830 is available in a 16-bump UCSP™ package (2.5mm x 2.5mm).
Applications
Cell Phones and Smartphones
PDAs and MP3 Players
Typical Operating Circuit
2.2μH TO
10μH
INPUT
2.7V TO 5.5V
PROGRAMMABLE
OUTPUT
3.8V TO 5.2V
UP TO 280mA
LX
OUT
IN
CIN
COUT
GND
♦ Flash LED Current Sink
I2C-Programmable Flash Output Current (Off to
200mA in 16 Steps)
I2C-Programmable Flash Maximum Timer (0.5s,
1.0s, 1.5s, or 2.0s)
I2C-Programmable Movie Output Current (Off to
200mA in 16 Steps)
Movie Enabled by I2C or Logic Input
Flash Enabled by Logic Input
Low Dropout (75mV typ)
♦ Four LED Current Sinks
Individually I2C-Programmable Output Current
Off to 10mA in 32 Steps
Low LED Sink Current Dropout Voltage (30mV typ)
♦ I2C Interface
Write Address (0x94), Read Address (0x95)
Individual On/Off and LED Current Settings
Simple Register Mapping
♦ < 1µA Shutdown Current
♦ Open/Short LED Detection
♦ Thermal-Shutdown Protection
♦ 16-Bump, 2.5mm x 2.5mm UCSP Package
PGND
MAX8830
COMP
Ordering Information
200mA FLASH
FLED
MOVIE ON
FLASH ON
MVON
FLEN
LED1
SCL
LED2
IC
TEMP
RANGE
PIN-PACKAGE
MAX8830EWE+T
-40°C to
+85°C
16-bump 2.5mm x
2.5mm UCSP
PKG
CODE
W162A2-1
+Denotes a lead-free package.
SDA
VLOGIC
PART
LED3
VDD
LED4
Pin Configuration appears at the end of data sheet.
UCSP is a trademark of Maxim Integrated Products, Inc.
________________________________________________________________ Maxim Integrated Products
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
1
MAX8830
General Description
MAX8830
LED Light Management IC in
2.5mm x 2.5mm UCSP
ABSOLUTE MAXIMUM RATINGS
IN, OUT to GND………………………....…………..-0.3V to +6.0V
IN, OUT to GND (maximum of 1µs) ....................................+7.0V
VDD to GND ...........................................................-0.3V to +4.0V
SCL, SDA, MVON, FLEN to GND..................-0.3V to VDD + 0.3V
COMP, FLED, LED_ to GND .......................-0.3V to VOUT + 0.3V
PGND to GND .......................................................-0.3V to +0.3V
Continuous ILX Current...............................................600mARMS
Continuous Power Dissipation (TA = +70°C)
16-Bump 2.5mm x 2.5mm UCSP
(derate 105.7mW/°C above +70°C) .............................750mW
Operating Temperature Range ...........................-40°C to +85°C
Junction Temperature ......................................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Bump Temperature* (soldering) ......................................+235°C
*This device is constructed using a unique set of packaging techniques that impose a limit on the thermal profile the device can be
exposed to during board level solder attach and rework. This limit permits only the use of the solder profiles recommended in the
industry-standard specification, JEDEC 020A, paragraph 7.6, Table 3 for IR/VPR and Convection reflow. Preheating is required.
Hand or wave soldering is not allowed.
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS
(VIN = 3.6V, VGND = VPGND = 0V, VDD = 3.0V, TA = -40°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1)
PARAMETER
DESCRIPTION
IN Operating Voltage
1.7
VDD falling
1.35
VDD UVLO Hysteresis
IN UVLO Threshold
TYP
2.7
VDD Operating Range
VDD Undervoltage Lockout (UVLO) Threshold
MIN
1.5
MAX
UNITS
5.5
V
3.6
V
1.65
V
50
VIN rising
2.25
IN UVLO Hysteresis
2.45
mV
2.65
50
VDD Standby Supply Current
SCL = SDA = VDD,
I2C ready
TA = +25°C
3
TA = +85°C
4
IN Standby Supply Current
SCL = SDA = VDD,
I2C ready
TA = +25°C
5
TA = +85°C
5
IN Shutdown Supply Current
All outputs off,
VDD = 0
TA = +25°C
0.1
TA = +85°C
1
Thermal-Shutdown Hysteresis
Thermal-Shutdown
V
mV
10
15
5
µA
µA
µA
20
°C
+160
°C
LOGIC AND I2C INTERFACE
MVON, FLEN
Logic Input-High Voltage
VDD = 1.7V to 3.6V
Logic Input-Low Voltage
VDD = 1.7V to 3.6V
Logic Input Current
VIL = 0V or VIH = 3.6V
SDA Output Low Voltage
ISDA = 3mA
SCL, SDA
1.6
V
0.7 x
VDD
MVON, FLEN
0.4
0.3 x
VDD
SCL, SDA
TA = +25°C
-1
TA = +85°C
0.01
+1
0.1
0.03
I2C Clock Frequency
V
µA
0.4
V
400
kHz
Bus-Free Time Between START and STOP
tBUF
1.3
Hold Time Repeated START Condition
tHD_STA
0.6
0.1
µs
SCL Low Period
tLOW
1.3
0.2
µs
2
µs
_______________________________________________________________________________________
LED Light Management IC in
2.5mm x 2.5mm UCSP
(VIN = 3.6V, VGND = VPGND = 0V, VDD = 3.0V, TA = -40°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1)
PARAMETER
DESCRIPTION
MIN
TYP
MAX
UNITS
SCL High Period
tHIGH
0.6
0.2
µs
Setup Time Repeated START Condition
tSU_STA
0.6
0.1
µs
µs
SDA Hold Time
tHD_DAT
0
-0.01
SDA Setup Time
tSU_DAT
100
50
ns
Setup Time for STOP Condition
tSU_STO
0.6
0.1
µs
STEP-UP DC-DC CONVERTER
IN Supply Current
1MHz switching, VOUT = 5V
OUT Voltage Range
100mV steps
OUT Voltage Accuracy
IOUT = 100mA
Line Regulation
VIN = 2.7V to 4.2V
Load Regulation
IOUT = 0 to 280mA
Maximum OUT Current
VIN ≥ 3.2V, VOUT = 5.0V
4
3.8
TA = +25°C
-1.5
TA = +85°C
-3
280
nFET Current Limit
±0.3
7.5
mA
5.2
V
+1.5
+3
%
0.1
%/V
0.5
%/A
500
mA
2.2
A
LX nFET On-Resistance
LX to PGND, ILX = 100mA
0.1
Ω
LX pFET On-Resistance
LX to OUT, ILX = 100mA
0.15
Ω
LX Leakage
VLX = 5.5V
Operating Frequency
TA = -40°C to +85°C
TA = +25°C
0.1
TA = +85°C
1
Maximum Duty Cycle
0.75
1.00
65
75
Minimum Duty Cycle
4
5
1.25
µA
MHz
%
8
%
COMP Transconductance
VCOMP = 1.5V
60
µS
COMP Discharge Resistance
During shutdown or UVLO, from COMP to GND
180
Ω
OUT Discharge Resistance
During shutdown or UVLO, from OUT to IN
10
kΩ
FLED CURRENT SINK DRIVER
IN Supply Current
Maximum Current Setting
Current Accuracy
Step-up off, FLED on
0.35
Flash (enabled by FLEN)
100
Movie (enabled by MVON or I2C)
50
50mA setting, Movie
Current-Regulator Dropout
FLED Leakage in Shutdown
TA = +25°C
TA = -40°C to +85°C
-3.0
±0.5
-5
50mA setting (Note 2)
0.6
mA
+3.0
+5
75
TA = +25°C
0.01
TA = +85°C
0.1
0.5
mA
%
mV
5
2.0
µA
Flash Duration Timer Range
In 500ms steps (Note 3)
Open-LED Detection Threshold
FLED enabled
100
mV
s
Shorted-LED Detection Threshold
FLED enabled
VOUT 1V
V
_______________________________________________________________________________________
3
MAX8830
ELECTRICAL CHARACTERISTICS (continued)
MAX8830
LED Light Management IC in
2.5mm x 2.5mm UCSP
ELECTRICAL CHARACTERISTICS (continued)
(VIN = 3.6V, VGND = VPGND = 0V, VDD = 3.0V, TA = -40°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1)
PARAMETER
DESCRIPTION
MIN
TYP
MAX
UNITS
0.2
0.5
mA
LED1–LED4 CURRENT SINK DRIVER
IN Supply Current
Step-up off, all current sinks on
Maximum Current Setting
Current Accuracy
10
LED1–LED4 = 10mA
setting, VOUT = VIN
3/32 setting, TA = +25°C
Current Regulator Dropout
Leakage in Shutdown
Open-LED Detection Threshold
Shorted-LED Detection Threshold
10mA setting (Note 2)
±0.3
mA
TA = +25°C
-2
+2
TA = 0°C to +85°C
-5
+5
TA = -40°C to +85°C
-8
+8
%
±7
30
125
TA = +25°C
0.01
5
TA = +85°C
0.1
mV
µA
LED_ enabled
100
mV
LED_ enabled
VOUT 1V
V
Note 1: All devices are 100% production tested at TA = +25°C. Limits over the operating temperature range are guaranteed by design.
Note 2: LED current sink dropout voltage is defined as the voltage at which current drops 10% from the current level measured at 0.6V.
Note 3: Flash duration is from rising edge of FLEN until IFLED turns off (or returns to the movie current setting if MVON is high).
4
_______________________________________________________________________________________
LED Light Management IC in
2.5mm x 2.5mm UCSP
98
100
90
VOUT = 5V
92
90
INPUT CURRENT (μA)
EFFICIENCY (%)
94
70
60
50
0
30
3.5
3.9
4.3
4.7
5.5
5.1
10
1
INPUT VOLTAGE (V)
100
2.7
1000
3.1
INPUT STANDBY SUPPLY
CURRENT vs. TEMPERATURE
3.5
3.9
4.3
4.7
5.1
5.5
INPUT VOLTAGE (V)
OUTPUT CURRENT (mA)
SWITCHING WAVEFORMS
(VOUT = 3.8V, IOUT = 280mA)
MAX8830 toc05
30
MAX8830 toc04
VOUT = VIN
ALL LEDs OFF
I2C READY
25
20
ILX
200mA/div
VLX
2V/div
15
10
5
0
-40
-15
10
35
60
400ns/div
85
TEMPERATURE (°C)
SWITCHING WAVEFORMS
(VOUT = 5V, IOUT = 280mA)
OSCILLATOR FREQUENCY
vs. TEMPERATURE
MAX8830 toc06
200mA/div
ILX
VLX
2V/div
MAX8830 toc07
1.20
OSCILLATOR FREQUENCY (MHz)
3.1
10
40
86
2.7
15
5
L1 = 10μH
TOKO 1098AS-100M
DE2812C SERIES
88
VOUT = VIN
ALL LEDs OFF
I2C READY
20
80
INPUT CURRENT (μA)
EFFICIENCY (%)
96
25
MAX8830 toc02
IOUT = 200mA
MAX8830 toc01
100
VOUT = 3.8V
INPUT STANDBY SUPPLY CURRENT
vs. INPUT VOLTAGE
STEP-UP CONVERTER EFFICIENCY
vs. OUTPUT CURRENT
MAX8830 toc03
STEP-UP CONVERTER EFFICIENCY
vs. INPUT VOLTAGE
1.15
1.10
1.05
1.00
0.95
0.90
400ns/div
-40
-15
10
35
60
85
TEMPERATURE (°C)
_______________________________________________________________________________________
5
MAX8830
Typical Operating Characteristics
(VIN = 3.6V, VOUT = 3.8V, VDD = 3.0V, circuit of Figure 1, TA = +25°C, unless otherwise noted.)
Typical Operating Characteristics (continued)
(VIN = 3.6V, VOUT = 3.8V, VDD = 3.0V, circuit of Figure 1, TA = +25°C, unless otherwise noted.)
1.05
1.00
0.95
0.90
3.80
5.05
3.79
5.04
VOUT = 3.8V
3.78
5.03
3.77
5.02
3.76
5.01
VOUT = 5V
3.75
5.00
3.74
4.99
3.73
4.98
3.72
3.1
3.5
3.9
4.3
4.7
5.1
ILED1
-0.5
ILED4
-1.0
-1.5
ILED2
-2.5
2.7
10 25 35 50 60 70 85
3.1
3.5
3.9
4.7
5.1
5.5
TEMPERATURE (°C)
INPUT VOLTAGE (V)
LED CURRENT ACCURACY
vs. TEMPERATURE
FLED CURRENT-REGULATOR
DROPOUT VOLTAGE vs. FLED CURRENT
LED_ CURRENT-REGULATOR
DROPOUT VOLTAGE vs. LED_ CURRENT
160
0.2
0
-0.2
-0.4
45
40
DROPOUT VOLTAGE (mV)
0.4
50
140
120
100
80
60
35
30
25
20
15
-0.6
40
10
-0.8
20
5
-1.0
0
-15
10
35
60
85
MAX8830 toc13
180
DROPOUT VOLTAGE (mV)
0.6
200
MAX8830 toc12
ILED = 10mA
0.8
0
0
TEMPERATURE (°C)
50
100
150
200
0
4
2
FLED CURRENT (mA)
STARTUP WAVEFORMS
SOFT-START
MAX8830 toc15
5V/div
VIN
VIN
2V/div
VOUT = 5V
500mV/div
VOUT = 3V
500mV/div
5V/div
VOUT
2V/div
VLX
VCOMP
20.0μs/div
6
LED_ CURRENT (mA)
MAX8830 toc14
6
4.3
INPUT VOLTAGE (V)
1.0
-40
ILED3
0
-2.0
4.97
-40 -25 -15 0
5.5
MAX8830 toc11
2.7
0.5
5.06
LED CURRENT ACCURACY (%)
1.10
5.07
3.81
OUTPUT VOLTAGE (V)
1.15
MAX8830 toc09
3.82
MAX8830 toc08
1.20
OSCILLATOR FREQUENCY (MHz)
LED CURRENT ACCURACY AND MATCHING
vs. INPUT VOLTAGE (ILED_ = 10mA)
OUTPUT VOLTAGE vs. TEMPERATURE
MAX8830 toc10
OSCILLATOR FREQUENCY
vs. INPUT VOLTAGE
LED CURRENT ACCURACY (%)
MAX8830
LED Light Management IC in
2.5mm x 2.5mm UCSP
100ms/div
_______________________________________________________________________________________
8
10
LED Light Management IC in
2.5mm x 2.5mm UCSP
UCSP
BUMP
NAME
FUNCTION
A1
FLED
Flash LED Current-Sink Regulator. Current flowing into FLED is based on the internal I2C registers.
Connect FLED to the cathode of an external flash LED or LED module. FLED is high impedance during
shutdown. If unused, FLED may be shorted to ground or left unconnected.
A2
PGND
Power Ground. Connect PGND to GND and to the input capacitor ground. Connect PGND to the PCB
ground plane.
A3
LX
Inductor Connection. Connect LX to the switched side of the inductor. LX is internally connected to the
drains of the internal MOSFETs. LX is high impedance in shutdown.
A4
OUT
Regulator Output. Connect OUT to the anodes of the external LEDs. OUT can also be used to supply
other circuits, such as audio amplifiers. Bypass OUT to PGND with a 10µF or larger ceramic capacitor.
During shutdown, VOUT is one diode drop below the VIN.
C1
B1
B2
D1
LED1
LED2
LED3
LED4
LED Current-Sink Regulators. Current flowing into LED_ is based on the internal I2C registers. Connect
LED_ to the cathodes of external LEDs. LED_ is high impedance during shutdown. If unused, LED_ can
be shorted to ground or left unconnected.
B3
MVON
Movie On Logic Input. Connect to VDD or drive with logic 1 to enable the movie mode. The FLED movie
current is set in the I2C registers. Connect to GND or drive with logic 0 to turn off the movie mode. The
movie mode is also enabled through the I2C interface.
B4
IN
Analog Supply Voltage Input. The input voltage range is 2.7V to 5.5V. Bypass IN to GND and PGND with
a 10µF ceramic capacitor as close as possible to the IC. IN is high impedance during shutdown.
C2
FLEN
Flash Enable Logic Input. A transition from logic 0 to logic 1 on FLEN initiates the flash mode. The flash
duration and FLED flash current are set in I2C registers. The flash mode terminates when either FLEN
transitions back to logic 0 or after the flash-duration timer expires.
C3
SCL
I2C Clock Input. Data is read on the rising edge of SCL.
C4
COMP
D2
GND
Analog Ground. Connect GND to PGND and to the input capacitor ground. Connect GND to the PCB
ground plane.
D3
SDA
I2C Data Input. Data is read on the rising edge of SCL.
D4
VDD
Logic Input Supply Voltage. Connect VDD to the logic supply driving SCL, SDA, MVON, and FLEN.
Bypass VDD to GND with a 0.1µF ceramic capacitor. Setting VDD = 0 places the part in shutdown.
Compensation Input. See the COMP Network Selection section for details.
_______________________________________________________________________________________
7
MAX8830
Pin Description
MAX8830
LED Light Management IC in
2.5mm x 2.5mm UCSP
L1*
10μH
VIN
2.7V TO 5.5V
OUT
nFET
IN
CIN
10μF
GND
CHIP POWER
AND
REFERENCE
COUT
10μF
pFET
PWM
BOOST
CONVERTER
+
PGND
RCOMP
VREF
COMP
4
1MHz
CCOMP
4
MOVIE ON /OFF
IOUT
280mA
MAX8830
LX
MVON
FLED
200mA
FLASH
LED
5
FLASH ON /OFF
FLEN
FLASH
MAX TIMER
(0.5/1.0/1.5/2.0s)
LED1
2
5
REGISTERS
AND
LOGIC
SCL
SERIAL
INTERFACE
VLOGIC
SDA
I2C
PORT
8
LED2
5
LED3
VDD
5
CVDD
0.1μF
LED4
*L1 = TOKO 1098AS-100M
Figure 1. Block Diagram and Typical Application Circuit
Detailed Description
The MAX8830 light management IC integrates a 280mA
PWM step-up DC-DC converter, a 200mA white LED
camera flash current sink, and four programmable LED
current sinks. An I2C interface controls individual on/off
of all outputs, step-up output voltage setting, movie/
flash current and flash timer-duration settings, and individual current sink settings. Figure 1 shows the block
diagram and typical application circuit.
8
Step-Up Converter (LX, OUT, COMP, PGND)
The MAX8830 includes a fixed-frequency, PWM step-up
converter that supplies power to the LEDs and additional
loads, such as audio amplifiers. The output voltage is
programmable from 3.8V to 5.2V (in 100mV steps)
through the I2C port. If the output voltage is not programmed, the step-up converter remains off; however, if
any of the current regulators are programmed, the boost
converter p-channel synchronous rectifier is turned on.
The step-up converter switches an internal power
MOSFET and synchronous rectifier at a constant 1MHz
frequency with varying duty cycle up to 75% to maintain
constant output voltage as VIN and load vary. Internal
circuitry prevents any unwanted subharmonic switching
by forcing a minimum 4% duty cycle.
_______________________________________________________________________________________
LED Light Management IC in
2.5mm x 2.5mm UCSP
A low-dropout linear current regulator from FLED to
PGND sinks current from an external flash LED cathode
terminal. The FLED current is regulated to I2C-programmable levels for movie mode (up to 200mA) and flash
mode (up to 200mA). The movie mode provides continuous lighting when enabled through I2C (see Table 1).
The flash mode is enabled only when FLEN goes high.
A flash maximum timer, programmable from 0.5s to
2.0s through I2C, limits the duration of the flash mode in
case FLEN remains high. The flash mode has priority
over the movie mode.
Current-Sink Regulators (LED1–LED4)
Four low-dropout linear current regulators from LED_ to
GND sink current from external LED cathode terminals.
The LED_ currents are individually regulated to an I2Cprogrammable level from off to 10mA in 32 steps, independently set for each LED_.
Undervoltage Lockout
The IC contains undervoltage lockout (UVLO) circuitry
that disables the device until VIN is greater than 2.45V
(typ). Once VIN rises above 2.45V (typ), the UVLO circuitry does not disable the IC until VIN falls below the
UVLO threshold hysteresis.
Soft-Start
The MAX8830 soft-starts by charging CCOMP with a
100µA current source. During this time, the internal
MOSFET is switching at the minimum duty cycle. Once
VCOMP rises above 1V, the duty cycle increases until the
output voltage reaches the desired regulation level.
COMP is pulled to GND with a 80Ω internal resistor during UVLO or shutdown. See the Typical Operating
Characteristics for an example of soft-start operation.
Shutdown and Standby
The MAX8830 is in shutdown when VDD = 0. In shutdown, supply current is reduced to 0.1µA (typ). The
MAX8830 is in standby when the step-up converter and
all LED outputs are turned off through I 2C (and by
keeping MVON and FLEN at logic 0). During this time,
the I2C port remains in standby (ready) state as long as
logic-high voltage is supplied to VDD.
CCOMP is discharged whenever the step-up converter is
turned off, allowing the device to reinitiate soft-start when
it is enabled. The internal MOSFET and synchronous rectifier are also high impedance when the step-up converter
is off; however, OUT is one diode drop below the input.
FLED and LED_ are high impedance in shutdown, so the
external LEDs are all off, but any external circuitry on OUT
(such as an audio amplifier) is not disconnected, and
therefore, should include its own shutdown capability.
Parallel Connection of
Current-Sink Regulators
The LED current-sink regulators (FLED and LED_) can
be connected in parallel in any combination to allow the
use of higher current LEDs or any other desired effects.
Unused current regulators may be left unconnected or
shorted to ground. The LED regulators must be disabled through I2C to avoid a fault detection from an
open or short.
Open/Short LED Detection
The MAX8830 includes 10 comparators to detect open
or shorted LEDs on the FLED and LED1–LED4 pins.
One comparator on each pin detects when the voltage
falls below 100mV, indicating an open LED fault.
Another comparator on each pin detects when the voltage rises above VOUT - 1V, indicating a shorted LED
fault. The fault-detection comparators are enabled only
when the corresponding current sink is enabled (and
not set to zero current). Once a fault is detected the two
comparators provide a single bit output (1 = fault, 0 =
no fault) corresponding to the appropriate pin. When a
read command (address 0x95) is issued to the
MAX8830, the status of each pin is latched into the status register (see Table 6) and subsequently written to
the I2C bus by the MAX8830.
Thermal Shutdown
Thermal shutdown limits total power dissipation in the
MAX8830. When the junction temperature exceeds
+160°C, the device turns off, allowing the IC to cool.
The IC turns on and begins soft-start after the junction
temperature cools by 20°C. This results in a pulsed output during continuous thermal-overload conditions.
_______________________________________________________________________________________
9
MAX8830
Flash Current-Sink Regulator
(FLED, MVON, FLEN)
MAX8830
LED Light Management IC in
2.5mm x 2.5mm UCSP
I2C Serial Interface
The I2C serial interface consists of a serial-data line
(SDA) and a serial-clock line (SCL). Standard I2C writebyte commands are used. Figure 2 shows a timing diagram for the I2C protocol. The MAX8830 is a slave-only
device, relying upon a master to generate a clock signal. The master (typically a microprocessor) initiates
data transfer on the bus and generates SCL to permit
data transfer. A master device communicates to the
MAX8830 by transmitting the proper 8-bit address
(0x94) followed by the 8-bit control byte. Each 8-bit
control byte consists of a command code (usually
3-bits) with the remaining bits (usually 5 bits) as data
(see Table 1). Each transmit sequence is framed by a
START (A) condition and a STOP (L) condition. Each
word transmitted over the bus is 8 bits long and is
always followed by an acknowledge clock pulse.
The step-up converter OUT voltage, FLED flash current
and duration, FLED movie current, and LED_ individual
currents are set using the I2C serial interface. Each current level is individually programmable (including off)
with a single command (see Tables 1, 2, and 3). While
the flash current is set through I2C, current does not
flow until the FLEN input is logic 1, as described in the
Flash Current-Sink Regulator (FLED, MVON, FLEN)
section. By default, the movie current is turned on when
a nonzero setting is programmed through I 2 C.
Alternately, by setting a bit in the “other” register, the
movie mode current may also be gated by logic 1 at
the MVON input.
A
tLOW
B
tHIGH
C
D
E
F
G
H
I
J
K
L
M
SCL
SDA
tSU_STA
tHD_STA
A = START CONDITION
B = MSB OF ADDRESS CLOCKED INTO SLAVE
C = LSB OF ADDRESS CLOCKED INTO SLAVE
D = R/W BIT CLOCKED INTO SLAVE
E = SLAVE PULLS SMBDATA LINE LOW
tSU_DAT
tHD_DAT
F = ACKNOWLEDGE BIT CLOCKED INTO MASTER
G = MSB OF DATA CLOCKED INTO SLAVE (OP/SUS BIT)
H = LSB OF DATA CLOCKED INTO SLAVE
I = SLAVE PULLS SMBDATA LINE LOW
tSU_STO
J = ACKNOWLEDGE CLOCKED INTO MASTER
K = ACKNOWLEDGE CLOCK PULSE
L = STOP CONDITION, DATA EXECUTED BY SLAVE
M = NEW START CONDITION
Figure 2. I2C Timing Diagram
10
______________________________________________________________________________________
tBUF
LED Light Management IC in
2.5mm x 2.5mm UCSP
MAX8830
Table 1. Control Data Byte
SDA CONTROL BYTE
FUNCTION
COMMAND
DATA
C2
C1
C0
D4
Step-Up OUT Voltage
0
0
0
0
3.8V to 5.2V and off in 16 steps
D3
Unused
0
0
0
0
Reserved for future use
LED1 Current
0
0
1
0
Off to 10mA in 32 steps
LED2 Current
0
1
0
0
Off to 10mA in 32 steps
LED3 Current
0
1
1
0
Off to 10mA in 32 steps
LED4 Current
1
0
0
0
Off to 10mA in 32 steps
Unused
1
0
1
0
Off to 10mA in 32 steps
Flash Current
1
1
0
0
Off to 200mA in 16 steps
Movie Current
1
1
1
0
Off to 200mA in 16 steps
Other
1
1
1
1
0
D2
MVON
enable
D1
D0
Flash duration
Note: C2 is MSB and D0 is LSB.
Table 2. Control Register Data Default Settings
SDA CONTROL BYTE
FUNCTION
Step-Up OUT Voltage
COMMAND
DATA
C2
C1
C0
D4
D3
0
0
0
0
Off (0000)
D2
Unused
0
0
0
0
Reserved for future use
LED1 Current
0
0
1
0
Off (00000)
LED2 Current
0
1
0
0
Off (00000)
LED3 Current
0
1
1
0
Off (00000)
LED4 Current
1
0
0
0
Off (00000)
Unused
1
0
1
0
Reserved for future use
Flash Current
1
1
0
0
Off (00000)
Movie Current
1
1
1
0
Off (0000)
Other
1
1
1
1
0
MV by
I2C (0)
D1
D0
0.5s (00)
Note: C2 is MSB and D0 is LSB.
______________________________________________________________________________________
11
MAX8830
LED Light Management IC in
2.5mm x 2.5mm UCSP
Table 3. Step-Up Voltage and LED Current Settings
OUT VOLTAGE (V) OR LED CURRENT (mA)
DATA
OUT
LED1
LED2
LED3
LED4
FLASH
MOVIE
D4
D3
D2
D1
D0
OFF
OFF
OFF
OFF
OFF
OFF
OFF
0
0
0
0
0
3.8
0.63
0.63
0.63
0.63
25.0
25.0
0
0
0
0
1
3.9
0.94
0.94
0.94
0.94
37.5
37.5
0
0
0
1
0
4.0
1.25
1.25
1.25
1.25
50.0
50.0
0
0
0
1
1
4.1
1.56
1.56
1.56
1.56
62.5
62.5
0
0
1
0
0
4.2
1.88
1.88
1.88
1.88
75.0
75.0
0
0
1
0
1
4.3
2.19
2.19
2.19
2.19
87.5
87.5
0
0
1
1
0
4.4
2.50
2.50
2.50
2.50
100.0
100.0
0
0
1
1
1
4.5
2.81
2.81
2.81
2.81
112.5
112.5
0
1
0
0
0
4.6
3.13
3.13
3.13
3.13
125.0
125.0
0
1
0
0
1
4.7
3.44
3.44
3.44
3.44
137.5
137.5
0
1
0
1
0
4.8
3.75
3.75
3.75
3.75
150.0
150.0
0
1
0
1
1
4.9
4.06
4.06
4.06
4.06
162.5
162.5
0
1
1
0
0
5.0
4.38
4.38
4.38
4.38
175.0
175.0
0
1
1
0
1
5.1
4.69
4.69
4.69
4.69
188.0
188.0
0
1
1
1
0
5.2
5.00
5.00
5.00
5.00
200.0
200.0
0
1
1
1
1
5.31
5.31
5.31
5.31
1
0
0
0
0
5.63
5.63
5.63
5.63
1
0
0
0
1
5.94
5.94
5.94
5.94
1
0
0
1
0
6.25
6.25
6.25
6.25
1
0
0
1
1
6.56
6.56
6.56
6.56
1
0
1
0
0
6.88
6.88
6.88
6.88
1
0
1
0
1
7.19
7.19
7.19
7.19
1
0
1
1
0
7.50
7.50
7.50
7.50
1
0
1
1
1
7.81
7.81
7.81
7.81
1
1
0
0
0
8.13
8.13
8.13
8.13
1
1
0
0
1
8.44
8.44
8.44
8.44
1
1
0
1
0
8.75
8.75
8.75
8.75
1
1
0
1
1
9.06
9.06
9.06
9.06
1
1
1
0
0
9.38
9.38
9.38
9.38
1
1
1
0
1
9.69
9.69
9.69
9.69
1
1
1
1
0
10.00
10.00
10.00
10.00
1
1
1
1
1
Note: Defaults in bold italics.
12
______________________________________________________________________________________
LED Light Management IC in
2.5mm x 2.5mm UCSP
For the latest application details on UCSP construction,
dimensions, tape carrier information, PCB techniques,
bump-pad layout, and recommended reflow temperature profile, as well as the latest information on reliability testing results, go to the Maxim website at
www.maxim-ic.com/ucsp for the Application Note:
UCSP-A Wafer-Level Chip-Scale Package.
Table 4. MVON Control Setting
SDA CONTROL BYTE
FUNCTION
COMMAND
C2
C1
DATA
C0
D4
D3
D2
D1
D0
Movie Enabled Through I 2C
1
1
1
1
X
0
X
X
Movie Enabled Through MVON Pin
1
1
1
1
X
1
X
X
Note: Defaults in bold italics.
Table 5. Flash Duration Settings
SDA CONTROL BYTE
FUNCTION
COMMAND
DATA
C2
C1
C0
D4
D3
D2
D1
D0
0.5s Flash
1
1
1
1
X
X
0
0
1.0s Flash
1
1
1
1
X
X
0
1
1.5s Flash
1
1
1
1
X
X
1
0
2.0s Flash
1
1
1
1
X
X
1
1
Note: Defaults in bold italics.
Table 6. Read (0x95) Status Register
SDA READ BYTE
FUNCTION
Fault Status
DATA
D7
D6
D5
D4
D3
D2
D1
D0
X
X
X
FLED
LED4
LED3
LED2
LED1
Note: 1 = fault, 0 = no fault
______________________________________________________________________________________
13
MAX8830
UCSP Applications Information
Table 4 lists the MVON control settings; Table 5 lists
flash duration settings. Table 6 shows the read (0x95)
status register.
MAX8830
LED Light Management IC in
2.5mm x 2.5mm UCSP
Table 7. Suggested Inductors
MANUFACTURER
Cooper (Coiltronics)
FDK
TDK
TOKO
SERIES
INDUCTANCE
(µH)
DCR
(mΩ)
ISAT
(A)
SD3114
2.2
110
1.74
3.0 x 3.0 x 1.45 = 13mm3
MIPF2520
2.2
80
1.3A
2.5 x 2.0 x 1.0 = 5mm3
MIPW3226
2.2
100
1.1
3.2 x 2.6 x 1.0 = 8mm3
VLF3012AT
2.2
10
88
360
1.0
0.49
2.8 x 2.6 x 1.2 = 9mm3
2.7
75
1.8
3.0 x 3.2 x 1.2 = 12mm3
10
325
0.78
3.0 x 3.2 x 1.2 = 12mm3
DE2812C
DIMENSIONS
(LTYP x WTYP x HMAX = VOLUME)
Inductor Selection
PCB Layout
The MAX8830 is designed to use a 2.2µH to 10µH
inductor. To prevent core saturation, ensure that the
inductor-saturation current rating exceeds the peak
inductor current for the application. Calculate the worstcase peak inductor current with the following formula:
Due to fast switching waveforms and high-current
paths, careful PCB layout is required. Connect GND
and PGND directly to the ground plane. The IN bypass
capacitor should be placed as close as possible to the
IC. RCOMP and CCOMP should be connected between
COMP and GND as close as possible to the IC.
Minimize trace lengths between the IC and the inductor, the input capacitor, and the output capacitor; keep
these traces short, direct, and wide. The ground connections of CIN and COUT should be as close together
as possible and connected to PGND. The traces from
the input to the inductor and from the output capacitor
to the LEDs may be longer. A sample layout is available
in the MAX8830 evaluation kit.
IPEAK =
VOUT × IOUT(MAX) VIN(MIN) × 0.5μs
+
0.9 × VIN(MIN)
2 ×L
Table 7 provides a list of suggested inductors.
Capacitor Selection
Bypass the input to GND and PGND using a ceramic
capacitor. A ceramic capacitor with X5R and X7R
dielectrics are recommended for their low ESR and
tighter tolerances over a wide temperature range. Place
the capacitor as close as possible to the IC. The recommended minimum value for the input capacitor is 10µF;
however, larger value capacitors can be used to reduce
input ripple at the expense of size and higher cost.
The output capacitance required depends on the maximum output current. A 10µF ceramic capacitor works
well in most situations, but a 4.7µF capacitor is acceptable for lower load currents.
COMP Network Selection
The step-up converter is compensated for stability through
an external compensation network from COMP to GND.
See Table 8 for recommended compensation components.
Table 8. Suggested Compensation
Networks
MAX8830
1
2
3
4
FLED
PGND
LX
OUT
LED2
LED3
MVON
IN
LED1
FLEN
SCL
COMP
LED4
GND
SDA
VDD
+
A
B
C
D
RCOMP
(kΩ)
CCOMP
(pF)
2.2µH Inductor (Dynamic Loads)
4.3
2200
4.7µH Inductor (Dynamic Loads)
3
4700
10µH Inductor (Dynamic Loads)
3
6800
Only LED Loads (2.2µH to 10µH)
0 (short)
22000
14
Pin Configuration
UCSP
(2.5mm x 2.5mm)
Chip Information
PROCESS: BiCMOS
______________________________________________________________________________________
LED Light Management IC in
2.5mm x 2.5mm UCSP
16L WAFER LEVEL.EPS
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 15
© 2007 Maxim Integrated Products
is a registered trademark of Maxim Integrated Products, Inc.
MAX8830
Package Information
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information
go to www.maxim-ic.com/packages.)