Control IC. MIC2186 Datasheet
Low Voltage PWM Control IC
Micrel’s MIC2186 is a high efficiency boost PWM control IC.
With its wide input voltage range of 2.9V to 14V, the MIC2186
can be used to efficiently boost voltages in 1- or 2-cell Li Ion
battery powered applications, as well as to boost voltages in
fixed 3.3V, 5V, or 12V systems. Its powerful 1.6Ω output
driver allows the MIC2186 to supply large output currents with
the selection of proper external MOSFETs.
The MIC2186 can be configured to operate at 100kHz,
200kHz, or 400kHz. With it’s fixed frequency PWM architec-
ture, and easily synchronized drive, the MIC2186 is ideal for
noise-sensitive telecommunications applications.
MIC2186 also features a low current shutdown mode of
0.5µA and programmable undervoltage lockout. A manually
selectable SKIP Mode allows high efficiencies in light load
The MIC2186 is available in 16 pin SOIC and QSOP package
options with an operating range from –40°C to 125°C.
• Input voltage range: 2.9V to 14V
• 1.6Ω output driver
• Oscillator frequency of 100kHz/200kHz/400kHz
• Frequency sync to 600kHz
• Front edge blanking
• PWM Current Mode Control
• Selectable light load SKIP mode
• 600µA quiescent current (SKIP-Mode)
• 0.5µA shutdown current
• Cycle-by-Cycle current limiting
• Frequency foldback protection
• Adjustable under-voltage lockout
• Precision 1.245V reference output
• 16 pin SOIC and QSOP package options
• Selectable 50% maximum duty cycle for flyback applica-
• DC power distribution systems
• Wireless Modems
• ADSL line cards
• SLIC power supplies
• 1-and 2-cell Li Ion battery operated equipment
100 / 200 / 400
100 / 200 / 400
–40°C to +125°C
–40°C to +125°C
VIN = 3.3V
VOUT = 12V
12V Output Efficiency
VIN = 3.3V
600 0.5 1 1.5 2 2.5 3
OUTPUT CURRENT (A)
Adjustable Output Boost Converter
Micrel, Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
16-pin Narrow Body SOP (M)
16-pin QSOP (QS)
Input voltage to control circuitry (2.9V to 14V).
SKIP (Input): Regulator operates in PWM mode (no pulse skipping) when
pin is pulled low, and skip mode when raised to Vdd. There is no automatic
switching between PWM and skip mode available on this device.
Soft start reduces the inrush current and delays and slows the output voltage
rise time. A 5µA current source will charge the capacitor up to Vdd.
Compensation (Output): Internal error amplifier output. Connect to a
capacitor or series RC network to compensate the regulator’s control loop.
Small signal ground: must be routed separately from other grounds to the (-)
terminal of Cout.
Feedback Input - regulates FB to 1.245V.
Enable/Undervoltage Lockout (input): A low level on this pin will power down
the device, reducing the quiescent current to under 0.5µA. This pin has two
separate thresholds, below 1.5V the output switching is disabled, and below
0.9V the device is forced into a complete micropower shutdown. The 1.5V
threshold functions as an accurate undervoltage lockout (UVLO) with 135mV
The 1.245V reference is available on this pin. A 0.1µF capacitor should be
connected form this pin to SGnd.
The (+) input to the current limit comparator. A built in offset of 100mV
between CSH and SGnd in conjunction with the current sense resistor sets
the current limit threshold level. This is also the (+) input to the current
3V internal linear-regulator output. Vdd is also the supply voltage bus for the
chip. Bypass to SGND with 1µF. Maximum source current is 0.5mA.
Frequency Synchronization (Input): Connect an external clock signal to
synchronize the oscillator. Leading edge of signal above 1.5V starts switch-
ing cycle. Connect to SGND if not used.
MOSFET driver power ground, connects to the bottom of the current sense
resistor and the (–) terminal of CIN.
High Duty Cycle. Sets duty cycle and frequency along with Freq/2. Logic
HIGH sets 85% maximum duty cycle. Logic LOW sets 50% maximum duty
cycle. See applications section for more information.
High current drive for N channel MOSFET. Voltage swing is from ground to
VIN. RON is typically 1.6Ω.
Sets duty cycle and frequency along with HiDC. See applications section for
Power input voltage to the gate drive circuitry (2.9V to 14V). This pin is
normally connected to the output voltage.
2 April 2005