Fairchild FEB137-002 User Manual - page 3
www.fairchildsemi.com
© 2007 Fairchild Semiconductor Corporation
3
FEB137/138_FAN2001/FAN2002 1 • Rev. 0.0.2
The following user guide supports the evaluation kit for the FAN2001 and FAN2002. It
should be used in conjunction with the device datasheet as well as Fairchild application
notes and technical support team. Visit Fairchild’s website at www.fairchildsemi.com.
1. Features
2.5 to 5.5V Input Range
Up to 1A Output Current
Adjustable Output from 0.8V to V
IN
Thermal Shutdown, Short-Circuit Protection, Soft Start, Output Over-Voltage Protection
1.3MHz Fixed-Frequency PWM Operation at Heavy Load and Burst Operation at Light Load
Up to 96% Efficiency, Synchronous Operation
Pb-Free, 6-lead 3x3mm MLP Package
2. Description
The FAN2001/2 Evaluation Board is a compact circuit including either the FAN2001
MPX or the FAN2002 MPX in a 3x3mm MLP package. Both models feature an external
resistor divider for varying output voltage and differ only in pin out. The FAN2001/2
demo board, a completely assembled and tested surface mount board, provides easy
probe access points to all inputs and outputs so that electrical characteristics and
waveforms can be easily measured.
3. Operation
1. Connect V
IN
(2.5 to 5.5V) and GND (0V).
2. Use a jumper to toggle the circuit between "ON" and "OFF" modes.
3. Observe that, for varying input levels, if V
IN
> V
OUT
+ 0.6V and I
LOAD
< 1A, V
OUT
remains
constant.
4. The output voltage level is V
OUT
= V
REF
(1 + (R1/R2)) where V
REF
= 0.8V (typical) and R2 =
10K. For V
OUT
= 1.2V, R1 is preset to 5K and for V
OUT
= 3.3V, R1 is preset to 31.25K.
Note: R2 and R1 values are reversed for FAN2002MPX.
5. To verify supply current in “ON” and “OFF” modes; observe that, in shutdown mode, supply
current drops below 1µA and in "ON" mode, I
Q
< 50µA.
6. If quiescent current is a key design parameter, a higher value feedback resistor R2 can be
used, along with a small bypass capacitor C
F
(e.g. R2 = 100K and C
F
= 10pF).
Figure 1.
FAN2001MPX Board
Figure 2.
FAN2002MPX Board