MAX15003 Datasheet, PDF (10/32 Pages) Maxim Integrated Products – Triple-Output Buck Controller with Tracking/Sequencing

Triple-Output Buck Controller with
Tracking/Sequencing
Pin Description
PIN
NAME
FUNCTION
RESET Timeout Capacitor Connection. Connect a timing capacitor from CT to SGND to set the RESET
1
CT
delay. CT sources 2µA into the timing capacitor. When the voltage at CT passes 2V, open-drain RESET
goes high impedance.
2
IN
Supply Input Connection. Connect to an external voltage source from 5.5V to 23V. For 4.5V to 5.5V input
application, connect IN and REG together.
3
REG
5V Regulator Output. Bypass with a 2.2µF ceramic capacitor to SGND.
Track/Sequence Select Input. Connect SEL to REG to configure as a triple tracker at startup or connect SEL
4
SEL
to SGND to configure as a triple sequencer or leave SEL unconnected to configure as a dual tracker and
independent sequencer. Note: When configured as a triple sequencer, each rail is independently enabled
using the EN_.
Controller 1 Power-Ground Connection. Connect the input filter capacitor’s negative terminal, the source of
5
PGND1 the synchronous MOSFET, and the output filter capacitor’s return to PGND1. Connect externally to SGND at
a single point near the input capacitor return terminal.
6
DL1
Controller 1 Low-Side Gate Driver Output. DL1 is the gate driver output for the synchronous MOSFET.
7
DREG1
Controller 1 Low-Side Gate Driver Supply. Connect externally to REG and the anode of the boost diode.
Connect a minimum of 0.1µF ceramic capacitor from DREG1 to PGND1.
8
LX1
Controller 1 High-Side MOSFET Source Connection/Synchronous MOSFET Drain Connection. Connect the
inductor and the negative side of the boost capacitor to LX1.
9
DH1
Controller 1 High-Side Gate Driver Output. DH1 drives the gate of the high-side MOSFET.
10
BST1
Controller 1 High-Side Gate Driver Supply. Connect BST1 to the cathode of the boost diode and to the
positive terminal of the boost capacitor.
Controller 1 Negative Current-Sense Input. Connect CSN1 to the synchronous MOSFET drain (connected to
11
CSN1
LX1). When using a current-sense resistor, connect CSN1 to the junction of a low-side MOSFET’s source
and the current-sense resistor. See Figure 11.
Controller 1 Positive Current-Sense Input. Connect CSP1 to the synchronous MOSFET source (connected to
12
CSP1
PGND1). When using a current-sense resistor, connect CSP1 to the PGND1 end of the current-sense
resistor.
Controller 1 Valley Current-Limit Set Output. Connect a 25kΩ to 150kΩ resistor, R_ILIM1, from ILIM1 to SGND
13
ILIM1
to program the valley current-limit threshold from 50mV to 300mV. ILIM1 sources 20µA out to R_ILIM1. The
resulting voltage divided by 10 is the valley current-limit threshold. When using a precision current-sense
resistor, connect a resistive divider from REG to ILIM1 to SGND to set the valley current limit. See Figure 11.
14
COMP1 ^{Controller1 Error Transconductance Amplifier Output. Connect COMP1 to the compensation feedback}
network.
Controller 1 Enable Input. EN1 must be above 1.24V, V_EN-TH, for the PWM controller to start Output 1.
15
EN1
Controller 1 is the master. Use the master as the highest output voltage in a coincident tracking
configuration.
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