Pin description, Typical operating characteristics (continued) – Rainbow Electronics MAX15001 User Manual
Page 7
MAX15000/MAX15001
Current-Mode PWM Controllers with
Programmable Switching Frequency
_______________________________________________________________________________________
7
Pin Description
PIN
NAME
FUNCTION
1
UVLO/EN
Externally Programmable Undervoltage Lockout. UVLO/EN programs the input start voltage. Connect
UVLO/EN to GND to disable the device. NDRV stops switching approximately 210µs after the UVLO/EN
voltage falls below 1.17V.
2
UFLG
Open-Drain Undervoltage Flag Output. UFLG is asserted low as soon as the UVLO/EN voltage falls below its
threshold.
3
FB
Error-Amplifier Inverting Input
4
COMP
Error-Amplifier Output
5
CS
Current-Sense Input. Current-sense connection for PWM regulation and cycle-by-cycle current limit.
Connect to the high side of the sense resistor. An RC filter may be necessary to eliminate leading-edge
spikes. Current-limit trip voltage is 1V.
6
RT
Oscillator Timing Resistor Input. An RC network may be required to reduce jitter (see the Typical Application
Circuit).
7
GND
Ground Connection
8
NDRV
External n-Channel MOSFET Gate Connection
9
V
CC
Gate-Drive Supply. Internally generated supply from IN. Decouple V
CC
with a 10nF or larger capacitor
to GND.
10
IN
IN Supply. Decouple with a 10nF or larger capacitor to GND. For bootstrapped operation (MAX15000),
connect a startup resistor from the input supply line to IN. Connect the bias winding supply to IN also (see
the Typical Operating Circuit). For the MAX15001, connect IN directly to the 9.5V to 24V supply.
NDRV HIGH OUTPUT IMPEDANCE
vs. TEMPERATURE
MAX15000 toc21
TEMPERATURE (
°C)
R
ON
(Ω
)
60
35
10
-15
3.4
3.8
4.2
4.6
5.0
3.0
-40
85
SOURCING 20mA
ERROR AMPLIFIER OPEN-LOOP GAIN
AND PHASE vs. FREQUENCY
FREQUENCY (Hz)
GAIN (dB)
PHASE (DEGREES)
100
-60
80
60
40
20
0
-20
-40
120
-200
80
40
0
-40
-80
-120
-160
1
0.1
10 100
1k
10k 100k 1M 10M 100M
MAX15000 toc22
GAIN
PHASE
Typical Operating Characteristics (continued)
(V
UVLO/EN
= +1.4V, V
FB
= +1V, COMP = open, V
CS
= 0V, T
A
= +25°C, unless otherwise noted.)