MAX6947ATE+ Maxim Integrated Products, MAX6947ATE+ Datasheet - Page 12
![IC LED DRIVER LINEAR 16-TQFN](/photos/6/66/66625/16-tqfn_exp_pad_21-0136_sml.jpg)
MAX6947ATE+
Manufacturer Part Number
MAX6947ATE+
Description
IC LED DRIVER LINEAR 16-TQFN
Manufacturer
Maxim Integrated Products
Type
Linear (I²C Interface)r
Datasheet
1.MAX6947ATE.pdf
(24 pages)
Specifications of MAX6947ATE+
Constant Current
Yes
Topology
Open Drain, PWM
Number Of Outputs
10
Internal Driver
Yes
Type - Primary
Backlight
Type - Secondary
RGB, White LED
Frequency
400kHz
Voltage - Supply
2.25 V ~ 3.6 V
Voltage - Output
7V
Mounting Type
Surface Mount
Package / Case
16-TQFN Exposed Pad
Operating Temperature
-40°C ~ 125°C
Current - Output / Channel
20mA
Internal Switch(s)
Yes
Number Of Segments
3
Low Level Output Current
21.12 mA
Operating Supply Voltage
2.25 V to 3.6 V
Maximum Supply Current
60 uA
Maximum Power Dissipation
1176 mW
Maximum Operating Temperature
+ 125 C
Mounting Style
SMD/SMT
Minimum Operating Temperature
- 40 C
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Efficiency
-
Lead Free Status / Rohs Status
Details
Table 7. Input Ports Registers
10-Port, Constant-Current LED Driver and
I/O Expander with PWM Intensity Control
Configure a port as a logic input by writing 0x01 to the
port’s output register (Table 4). Reading an input port
register returns the logic levels from the I/O ports con-
figured as a logic input (Table 7). The input port regis-
ter returns logic 0 in the appropriate bit position for a
port not configured as a logic input.
The input port’s registers are read only. The MAX6946/
MAX6947 ignore a write to input ports register.
The active-low RST input operates as a reset that voids
any current I
MAX6947, forcing the devices into the I
tion. Use the D6 bit in the configuration register to con-
figure RST to reset all the internal registers to the
power-on reset state (Tables 2 and 3). The RST input is
overvoltage tolerant to 6V.
The MAX6946/MAX6947 ignore all I
RST remains low. The MAX6946/MAX6947 use this fea-
ture to minimize supply current in power-critical applica-
tions by effectively disconnecting the MAX6946/
MAX6947 from the bus during idle periods. RST also
operates as a bus multiplexer, allowing multiple
MAX6946/MAX6947s to use the same I
Drive only one MAX6946/MAX6947 RST input high at any
time to use RST as a bus multiplexer.
Figure 3. Staggered PWM Waveform
12
DESCRIPTION
______________________________________________________________________________________
Input ports
Input ports
P9 and P8
0
P7–P0
32
OUTPUTS P0, O8 IN-PHASE PWM PERIOD
7.8125ms NOMINAL PWM PERIOD
64
2
C transaction involving the MAX6946/
OUTPUT P1, O9 STAGGERED PWM PERIOD
96
OUTPUT P2 STAGGERED PWM PERIOD
Ports Configured as Inputs
128
CODE (HEX)
ADDRESS
OUTPUT P3 STAGGERED PWM PERIOD
0x0E
0x0F
160
OUTPUT P4 STAGGERED PWM PERIOD
192
OUTPUT P5 STAGGERED PWM PERIOD
224
2
C bus activity while
OUTPUT P6 STAGGERED PWM PERIOD
Port P7
2
C slave address.
256
D7
0
2
OUTPUT P7 STAGGERED PWM PERIOD
C stop condi-
RST Input
OUTPUTS P0, O8 IN-PHASE PWM PERIOD
Port P6
OUTPUT P1, O9 STAGGERED PWM PERIOD
D6
0
NEXT PWM PERIOD
OUTPUT P2 STAGGERED PWM PERIOD
Port P5
OUTPUT P3 STAGGERED PWM PERIOD
D5
0
The MAX6946/MAX6947 feature a Reset Run option so
that simply taking the RST input high brings the driver
out of shutdown in addition to its normal function of
enabling the devices’ I
Configuring all the ports as logic inputs or outputs (all
output registers set to value 0x00 or 0x01) or LED off
(output register set to value 0xFF) puts the MAX6946/
MAX6947 into standby mode. Put the MAX6946/
MAX6947 into standby mode for lowest supply-current
consumption.
Setting a port as a constant-current output increases
the operating current (output register set to a value
between 0x02 and 0xFE), even if a load is not applied
to the port. The MAX6946/MAX6947 enable an internal
current mirror to provide the accurate constant-current
sink. Enabling the internal current mirror increases the
devices’ supply current. Each output contains a gated
mirror, and each mirror is only enabled when required.
In PWM mode, the current mirror is only turned on for
the output’s on-time. This means that the operating cur-
rent varies as constant-current outputs are turned on
and off through the serial interface, as well as by the
PWM intensity control.
OUTPUT P4 STAGGERED PWM PERIOD
OUTPUT P5 STAGGERED PWM PERIOD
Port P4
Standby Mode and Operating Current
REGISTER BIT
D4
0
OUTPUT P6 STAGGERED PWM PERIOD
OUTPUT P7 STAGGERED PWM PERIOD
Port P3
OUTPUTS P0, O8 IN-PHASE PWM PERIOD
D3
0
OUTPUT P1, O9 STAGGERED PWM PERIOD
2
C interface.
NEXT PWM PERIOD
Port P2
D2
0
Port P1
Port P9
D1
Port P0
Port P8
D0