MIC2184

Features:

• Input voltage range: 2.9V to 14V
• >90% efficiency
• Oscillator frequency of 400kHz
• Frequency divide-by-two pin
• Frequency sync to 600kHz
• FrequOut oscillator output allows simple charge pump implementation in low voltage systems
• 1.245V reference output
• Front edge blanking
• 5 output driver
• Soft start
• PWM current mode control
• 1A shutdown current
• Cycle-by-cycle current limiting
• Frequency foldback short circuit protection
• Adjustable under-voltage lockout
• 16 pin narrow-body SOIC and QSOP package options




Application

• 3.3V to 2.5V/1.8V/1.5V conversion
• DC power distribution systems
• Wireless Modems
• ADSL line cards
• 1-and 2-cell Li Ion battery operated equipment
• Satellite Phones




Pinout






Specifications

Supply Voltage (V_INA, V_INP) ......................................15V
Digital Supply Voltage (V_DD) .......................................7V
Comp Pin Voltage (V_COMP) ....................... 0.3V to +3V
Feedback Pin Voltage (V_FB) ...................... 0.3V to +3V
Enable Pin Voltage (V_EN/UVLO) .................. 0.3V to 15V
Current Sense Voltage (V_CSHV_CSL) .......... 0.3V to 1V
Sync Pin Voltage (V_SYNC) ............................ 0.3V to 7V
Freq/2 Pin Voltage (V_FREQ/2) ........................ -0.3V to 7V
Power Dissipation (P_D)
16 lead SOIC ............................... 400mW @ T_A = 85°C
16 lead QSOP .............................. 245mW @ T_A = 80°C
Ambient Storage Temp ................... 65°C to +150°C
ESD Rating, ......................................................... Note 3




Description

Micrel's MIC2184 is a high efficiency PWM buck control IC. With its wide input voltage range of 2.9V to 14V, the MIC2184 can be used to efficiently step voltages down in 1- or 2-cell Li Ion battery powered applications, as well as in fixed 3.3V, 5V, or 12V systems.

Efficiencies over 90% are achievable over a wide range of load conditions with the MIC2184's PWM control scheme. The operating frequency can be divided by two by raising the FREQ/2 pin to VDD. This allows the user to optimize efficiency versus board space. It also allows the MIC2184 to be externally synchronized to frequencies below its nominal 400KHz.

The MIC2184 features an oscillator output, FreqOut, which can be used to implement a simple charge pump in low voltage applications. The output of the charge pump MIC2184 can be fed into the gate drive power circuitry via the VINP pin, allowing enhanced gate drive, hence higher efficiencies, despite low input voltages.

MIC2184 features a 1A shutdown mode, and a programmable undervoltage lockout, making it well suited for portable applications.

The MIC2184 is available in 16 pin SOP and QSOP package options with a junction temperture range range from 40°C to +125°C.