MIC2870 Datasheet, PDF (3/25 Pages) Micrel Semiconductor – 1.5A Synchronous Boost Flash LED Driver with I2C Interface

Micrel, Inc.
MIC2870
Pin Description (Continued)
Pin Number
7, 15
8
9
10
11
12
13
14
16
EP
Pin Name
PGND
TRSET
LED2
LED1
TEN
OUT
EN
SW
SDA
ePad
Pin Function
Power Ground. PGND is used for the switching NMOS and PMOS of boost converter, and power
ground for LED current sinks.
Torch-Mode Current Level Programming. Connect a resistor from TRSET to AGND to set the
maximum current in the torch mode. For example, a 10kΩ resistor sets the LED sink current to its
maximum value of 187.5mA per channel. TRSET can be grounded if the default maximum torch-
mode current (187.5mA) is desired. TRSET, however, cannot be left floating and the maximum
resistance is limited to 80kΩ.
Channel 2 LED Current Sink. Connect the LED anode to OUT and cathode to LED2.
Channel 1 LED Current Sink. Connect the LED anode to OUT and cathode to LED1.
Torch-Mode Enable. Initiates torch mode when TEN is HIGH. If TEN is left floating, it is pulled-
down internally by a built-in 1µA current source when the device is enabled.
Boost Converter Output.
Enable (IC). The MIC2870 is in standby mode when EN is asserted HIGH. If EN is driven low for
more than 1s, the IC is shut down. Alternatively, the I²C interface can be used for
enabling/disabling the IC through the master control/status register. EN is pulled down by an
internal resistor.
Inductor Connection. It is connected to the internal power MOSFETs.
High-Speed Mode (3.4MHz) I²C Data Input/Output.
Exposed Heat Sink Pad. Connect to PGND ground plane for best thermal performance. This pin
is internally connected to PGND.
September 5, 2013
3
Revision 1.0