Micrel MIC2196 User Manual
MIC2196 Micrel
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MIC2196
400kHz SO-8 Boost Control IC
Final Information
General Description
Micrel’s MIC2196 is a high efficiency PWM boost control IC
housed in a SO-8 package. The MIC2196 is optimized for low
input voltage applications. With its wide input voltage range
of 2.9V to 14V, the MIC2196 can be used to efficiently boost
voltages in 3.3V, 5V, and 12V systems, as well as 1- or 2-cell
Li Ion battery powered applications. Its powerful 2Ω output
driver allows the MIC2196 to drive large external MOSFETs.
The MIC2196 is ideal for space-sensitive applications. The
device is housed in the space-saving SO-8 package, whose
low pin-count minimizes external components. Its 400kHz
PWM operation allows a small inductor and small output
capacitors to be used. The MIC2196 can implement allceramic capacitor solutions.
Efficiencies over 90% are achievable over a wide range of
load conditions with the MIC2196’s PWM boost control
scheme. Its fixed frequency PWM architecture also makes
the MIC2196 is ideal for noise-sensitive telecommunications
applications.
MIC2196 features a low current shutdown mode of 1µA and
programmable undervoltage lockout.
The MIC2196 is available in an 8-pin SOIC package with a
junction temperature range from –40°C to +125°C.
Features
• 2.9V to 14V input voltage range
• >90% efficiency
• 2Ω output driver
• 400kHz oscillator frequency
• PWM current mode control
• 0.5µA micro power shutdown
• Programmable UVLO
• Front edge blanking
• Cycle-by-cycle current limiting
• Frequency foldback short-circuit protection
• 8-pin SOIC package
Applications
• Step-up conversion in telecom/datacom systems
• SLIC power supplies
• SEPIC power supplies
• Low input voltage flyback and forward converters
• Wireless modems
• Cable modems
• ADSL line cards
• Base stations
• 1-and 2-cell Li Ion battery operated equipment
T ypical Application
V
1µF
5V
47µF
16V
IN
10nF
10k
4.7µH
MIC2196BM
VIN
EN/
UVLO
VDD
COMP
OUTN
CS
GND
FB
Si4884
(×2)
0.01Ω
B530
10k
1.15k
Adjustable Output Boost Converter
Micrel, Inc. • 1849 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
August 2004 1 MIC2196
V
OUT
12V, 3A
120µF
20V
(×3)
MIC2196
5V to 12V Efficiency
100
95
90
85
80
75
70
65
EFFICIENCY (%)
60
55
50
0 0.5 1 1.5 2 2.5 3 3.5 4
OUTPUT CURRENT (A)
VIN = 5V
MIC2196 Micrel
Ordering Information
Part Number Output Voltage Frequency Junction Temp. Range Package
Standard Pb-Free
MIC2196BM MIC2196YM Adjustable 400KHz –40°C to +125°C 8-lead SOIC
Pin Configuration
FB
EN/UVLO
CS
Pin Description
Pin Number Pin Name Pin Function
1 COMP Compensation (Output): Internal error amplifier output. Connect to a
2 FB Feedback (Input): Regulates FB to 1.245V.
3 EN/UVLO Enable/Undervoltage Lockout (input): A low level on this pin will power down
4 CS The (+) input to the current limit comparator. A built in offset of 100mV
5 VDD 3V internal linear-regulator output. VDD is also the supply voltage bus for the
6 GND Ground.
7 OUTN High current drive for N channel MOSFET. Voltage swing is from ground to
8 VIN Input voltage to the control IC. This pin also supplies power to the gate drive
1COMP
2
3
4
8 VIN
OUTN
7
GND
6
VDD
5
8 Lead SOIC (M)
capacitor or series RC network to compensate the regulator’s control loop.
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 100mV
hysteresis.
between CS and GND in conjunction with the current sense resistor sets the
current limit threshold level. This is also the (+) input to the current amplifier.
chip. Bypass to GND with 1µF.
VIN. RON is typically 3Ω @ 5VIN.
circuit.
MIC2196 2 August 2004
MIC2196 Micrel
Absolute Maximum Ratings (Note 1)
Supply Voltage (V
Digital Supply Voltage (VDD) ...........................................7V
Comp Pin Voltage (V
Feedback Pin Voltage (VFB) .......................... –0.3V to +3V
Enable Pin Voltage (V
) .....................................................15V
IN
)............................ –0.3V to +3V
COMP
EN/UVLO
) ..................... –0.3V to 15V
Operating Ratings (Note 2)
Supply Voltage (V
Junction Temperature ....................... –40°C ≤ TJ ≤ +125°C
Package Thermal Resistance
θJA 8-lead SOIC ................................................140°C/W
) .................................... +2.9V to +14V
IN
Current Sense Voltage (VCS) ......................... –0.3V to +1V
Power Dissipation (PD) ..................... 285mW @ TA = 85°C
Ambient Storage Temperature................. –65°C to +150°C
ESD Rating, Note3 ....................................................... 2kV
Electrical Characteristics
VIN = 5V, V
Parameter Condition Min Typ Max Units
Regulation
Feedback Voltage Reference (±1%) 1.233 1.245 1.258 V
Feedback Bias Current 50 nA
Output Voltage Line Regulation 3V ≤ VIN ≤ 9V +0.08 % / V
Output Voltage Load Regulation 0mV ≤ VCS ≤ 75mV –1.2 %
Output Voltage Total Regulation 3V ≤ VIN ≤ 9V ; 0mV ≤ VCS ≤ 75mV (±3%) 1.208 1.282 V
Input & VDD Supply
VIN Input Current (IQ) (excluding external MOSFET gate current) 1 2 mA
Shutdown Quiescent Current V
Digital Supply Voltage (VDD)I
Digital Supply Load Regulation IL = 0 to 5mA 0.1 V
Undervoltage Lockout VDD upper threshold (turn on threshold) 2.65 V
UVLO Hysteresis 100 mV
Enable/UVLO
Enable Input Threshold 0.6 0.9 1.2 V
UVLO Threshold 1.4 1.5 1.6 V
Enable Input Current V
Current Limit
Current Limit Threshold Voltage (Voltage on CS to trip current limit) 90 110 130 mV
Error Amplifier
Error Amplifier Gain 20 V/V
Current Amplifier
Current Amplifier Gain 3.7 V/V
Oscillator Section
Oscillator Frequency (fO) 360 400 440 kHz
Maximum Duty Cycle VFB = 1.0V 85 %
Minimum On Time VFB = 1.5V 165 ns
Frequency Foldback Threshold Measured on FB 0.3 V
Frequency Foldback Frequency 90 kHz
= 12V, TA = 25°C. Bold values indicate –40°C<TJ<+125°C; unless otherwise specified.
OUT
(±2%) 1.220 1.245 1.270 V
EN/UVLO
= 0 2.82 3.0 3.18 V
L
EN/UVLO
= 0V 0.5 5 µA
= 5V 0.2 5 µA
August 2004 3 MIC2196
MIC2196 Micrel
Parameter Condition Min Typ Max Units
Gate Drivers
Rise/Fall Time CL = 3300pF 25 ns
Output Driver Impedance Source, VIN = 12V 2 6 Ω
Sink, VIN = 12V 2 6 Ω
Source, V
Sink, VIN = 5V 3 7 Ω
= 5V 3 7 Ω
IN
Note 1. Absolute maximum ratings indicate limits beyond which damage to the component may occur. Electrical specifications do not apply when
Note 2. The device is not guaranteed to function outside its operating rating.
Note 3. Devices are ESD sensitive, handling precautions required. Human body model, 1.5kΩ in series with 100pF.
operating the device outside of its operating ratings. The maximum allowable power dissipation is a function of the maximum junction
temperature, T
, the junction-to-ambient thermal resistance, θJA, and the ambient temperature, TA.
J(Max)
MIC2196 4 August 2004
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