MIC23099_14 Datasheet, PDF (2/26 Pages) Micrel Semiconductor – Single AA/AAA Cell Step-Up/Step-Down Regulators with Battery Monitoring

Micrel, Inc.
MIC23099
Ordering Information
Part Number
Output
Voltages
Marking⁽¹⁾
Junction
Temperature Range
Package⁽²⁾
MIC23099YFT Adjustable
23099
–40°C to +125°C 14-Pin 2.5mm × 2.5mm × 0.55mm Thin QFN
Notes:
1. Pin 1 identifier = “▲”.
2. Thin QFN is a Green RoHs-compliant package. Lead finish is NiPdAu. Mold compound is Halogen Free.
Lead
Finish
Pb-Free
Pin Configuration
14-Pin 2.5mm × 2.5mm QFN (FT)
(Top View)
Pin Description
Pin
Number
1
2
3
4
5
6
Pin Name Pin Function
PGND1
VIN
FB1
NC
PG
EN
Power Ground 1: The power ground for the synchronous boost DC/DC converter power stage.
Battery Voltage Supply (Input): The internal circuitry operates from the battery voltage during start up.
Once VOUT1 exceeds VIN, the bias current comes from VOUT1. The start-up sequence is initiated once the
battery voltage is above 0.9V. The boost output (VOUT1) is power-up first, then the buck output (VOUT2)
follows. If the battery voltage falls below 0.85V for more than 15 cool-off cycles, both outputs are
simultaneously turned off and an internal resistor discharges the output capacitors to 0V.
Feedback 1 (Input): Connect a resistor divider network to this pin to set the output voltage for the
synchronous boost regulator. Resistors should be selected based on a nominal VFB1 = 0.6V.
No Connect Pin (NC): Leave open, do not connect to ground.
Power Good (Output): This is an open drain, active high output. When VIN, VFB1 or VFB2 are below their
nominal voltages the Power Good output gets pulled low after a de-glitch period. The PG pin will be
pulled low without delay when the enable is set low.
Enable (input): A logic level control of both outputs. The EN pin is CMOS-compatible. Logic high =
enable, logic low = shutdown. In the off state, supply current of the device is greatly reduced (typically
1µA). When the EN pin goes high, the start-up sequence is initiated. The boost output (VOUT1) is
powered up first then the buck output (VOUT2) follows. When EN goes low, both outputs are immediately
turned off and the boost output (VOUT1) is completely disconnected from the input voltage. Then both
converters output capacitors are discharged to ground through an internal pull down circuit. The EN pin
has a 4MΩ resistance to AGND.
August 6, 2014
2
Revision 1.3