RT9277A Datasheet, PDF (5/12 Pages) Richtek Technology Corporation – High Performance, Low Noise Boost Converter

Preliminary
RT9277A/B
Absolute Maximum Ratings (Note 1)
z Supply Voltage (V_IN) -------------------------------------------------------------------------------------------------- −0.3 to 6V
z LX to GND --------------------------------------------------------------------------------------------------------------- − 0.3V to 16V
z The other pins ---------------------------------------------------------------------------------------------------------- − 0.3V to 6V
z Power Dissipation, P_D @ T_A = 70°C
MSOP-8 ----------------------------------------------------------------------------------------------------------------- 625mW
z Package Thermal Resistance (Note 4)
MSOP-8, θ_JA ------------------------------------------------------------------------------------------------------------ 160°C/W
z Junction Temperature ------------------------------------------------------------------------------------------------- 150°C
z Lead Temperature (Soldering, 10 sec.) --------------------------------------------------------------------------- 260°C
z Storage Temperature Range ---------------------------------------------------------------------------------------- − 65°C to 150°C
z ESD Susceptibility (Note 2)
HBM (Human Body Mode) ------------------------------------------------------------------------------------------ 2kV
MM (Machine Mode) -------------------------------------------------------------------------------------------------- 200V
Recommended Operating Conditions (Note 3)
z Junction Temperature Range ---------------------------------------------------------------------------------------- −40°C to 125°C
z Ambient Temperature Range ---------------------------------------------------------------------------------------- −40°C to 85°C
Electrical Characteristics
(V_IN = 3V, FREQ left floating, T_A = 25°C, Unless Otherwise specification)
Parameter
Symbol
Test Condition
Min
System Supply Input
Operation voltage Range
V_IN
2.5
Under Voltage Lock Out
UVLO
1.9
Power On Reset Hysteresis
--
Quiescent Current
I_Q
Shut Down Current
Soft start Current (RT9277B)
Switching Regulator Oscillator
I_SHDN
I_SS
V_FB = 1.3V, No switching
--
V_FB = 1.0V, Switching, No load --
EN = GND
--
V_SS = 1.2V
1.5
FREQ = GND
540
Free Run Frequency
f_OSC
FREQ = V_IN
--
Maximum Duty Cycle
82
Reference Voltage
Feedback Reference Voltage
Error Amplifier
V_REF
V_COMP = 1.24V
1.222
Transconductance
G_m
70
Voltage Gain
A_V
--
Typ Max Units
--
5.5
V
2
2.1
V
100
--
mV
250 350 μA
2
5
mA
--
1
μA
4
7
μA
640 740 kHz
1200
--
kHz
90
96
%
1.24 1.258 V
140 240 μΩ
700
--
V/V
To be continued
DS9277A/B-02 March 2007
www.richtek.com
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