MIC3808/3809 Micrel
MIC3808/3809 4 April 2005
Electrical Characteristics
T
A
= T
J
= –40°C to +85°C, V
DD
= 10V (Note 9), 1µF capacitor from V
DD
to GND, R = 22KΩ, C = 330pF.
Parameter Condition Min Typ Max Units
Oscillator Section
Oscillator Frequency 180 200 220 kHz
Oscillator Amplitude/VDD Note 4 0.44 0.5 0.56 V/V
Error Amp Section
Input Voltage COMP = 2V 1.95 2 2.05 V
Input Bias Current –1 1 µA
Open Loop Voltage Gain (Guaranteed by design) 60 80 dB
COMP Sink Current FB = 2.2V, COMP = 1V 0.3 2.5 mA
COMP Source Current FB = 1.3V, COMP = 3V, Note 5 –0.15 –0.5 mA
COMP Clamp Voltage V
FB
= 0V 3.1 3.6 4.0 V
PWM Section
Maximum Duty Cycle Measured at OUTA or OUTB 48 49 50 %
Minimum Duty Cycle COMP = 0V 0%
Current Sense Section
Gain Note 6 (Guaranteed by design) 1.9 2.2 2.5 V/V
Maximum Input Signal Note 7 0.45 0.5 0.55 V
CS to Output Delay COMP = 3V, CS from 0 to 600mV 70 200 ns
CS Source Current –200 nA
CS Sink Current CS = 0.5V, RC = 5.5V, Note 8 510 mA
Over Current Threshold 0.7 0.75 0.8 V
COMP to CS Offset CS = 0V 0.35 0.8 1.2 V
Output Section
OUT Low Level I = 100mA 0.5 1 V
OUT High Level I = –50mA, V
DD
- OUT 0.5 1 V
Rise Time C
L
= 1nF 25 60 ns
Fall Time C
L
= 1nF 25 60 ns
Absolute Maximum Ratings (Note 1)
Supply Voltage (I
DD
≤ 10mA) ...................................... +15V
Supply Current ........................................................... 20mA
OUTA/OUTB Source Current (peak).......................... –0.5A
OUTA/OUTB Sink Current (peak) ................................ 1.0A
Comp Pin ......................................................................V
DD
Analog Inputs (FB, CS) ........................ –0.3V to V
DD
+0.3V
NOT TO EXCEED 6V
Junction Temperature .............................. –55°C to +150°C
Storage Temperature ............................... –65°C to +150°C
Lead Temperature (soldering, 10 sec.) ................... +300°C
ESD Rating, Note 3 ...................................................... 2kV
Operating Ratings (Note 2)
V
DD
Input Voltage (V
DD
) ........................................ Note 11
Oscillator Frequency (f
OSC
) ....................... 10kHz to 1MHz
Ambient Temperature (T
A
) ......................... –40°C to +85°C
Package Thermal Resistance
SOIC-8 (θ
JA
) ...................................................... 160°C/W
MSOP-8 (θ
JA
) .................................................... 206°C/W
