Datasheet

Connection Diagram
30030802
Top View
eTSSOP-16 Package
Ordering Information
Order Number Package Type NSC Package Drawing Package Marking Supplied As
LM20154MH eTSSOP-16 MXA16A 20154MH 92 Units of Rail
LM20154MHE 250 Units of Tape and Reel
LM20154MHX 2500 Units of Tape and Reel
Pin Descriptions
Pin # Name Description
1 SS/TRK Soft-Start or Tracking control input. An internal 5 µA current source charges an external capacitor to
set the Soft-Start ramp rate. If driven by a external source less than 800 mV, this pin overrides the
internal reference that sets the output voltage. If left open, an internal 1ms Soft-Start ramp is activated.
2 FB Feedback input to the error amplifier from the regulated output. This pin is connected to the inverting
input of the internal transconductance error amplifier. An 800 mV reference connected to the non-
inverting input of the error amplifier sets the closed loop regulation voltage at the FB pin.
3 PGOOD Power good output signal. Open drain output indicating the output voltage is regulating within
tolerance. A pull-up resistor of 10 to 100 kΩ is recommend for most applications.
4 COMP External compensation pin. Connect a resistor and capacitor to this pin to compensate the device.
5,16 NC These pins must be connected to GND to ensure proper operation.
6,7 PVIN Input voltage to the power switches inside the device. These pins should be connected together at the
device. A low ESR capacitor should be placed near these pins to stabilize the input voltage.
8,9 SW Switch pin. The PWM output of the internal power switches.
10,11 PGND Power ground pin for the internal power switches.
12 EN Precision enable input for the device. An external voltage divider can be used to set the device turn-
on threshold. If not used the EN pin should be connected to PVIN.
13 VCC Internal 2.7V sub-regulator. This pin should be bypassed with a 1 µF ceramic capacitor.
14 AVIN Analog input supply that generates the internal bias. Must be connected to VIN through a low pass
RC filter.
15 AGND Quiet analog ground for the internal bias circuitry.
16 SYNCOUT Frequency synchronization output. This NMOS open drain output provides a signal that has the same
frequency as the internal oscillator, but is shifted by 180 degrees.
EP Exposed Pad Exposed metal pad on the underside of the package with a weak electrical connection to ground. It is
recommended to connect this pad to the PC board ground plane in order to improve heat dissipation.
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