Datasheet

High-Voltage, 2.2MHz, 2A Automotive Step-
Down Converter with Low Operating Current
MAX16974
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Pin Description
PIN NAME FUNCTION
1 CRES
Analog Reset Timer. CRES sources 10FA (typ) of current into an external capacitor to set the reset
timeout period. Reset timeout period is defined as the time between the start of output regulation
and RES going high impedance. Leave unconnected for minimum delay time.
2 FOSC
Resistor-Programmable Switching-Frequency Setting Control Input. Connect a resistor from FOSC
to GND to set the switching frequency.
3 FSYNC
Synchronization Input. The device synchronizes to an external signal applied to FSYNC. The
external signal period must be 10% shorter than the internal clock period for proper operation.
4 I.C. Internally Connected. Connect to GND.
5 COMP
Error Amplifier Output. Connect an RC network from COMP to GND for stable operation. See the
Compensation Network section for more details.
6 FB
Feedback Input. Connect an external resistive divider from OUT to FB and GND to set the output
voltage. Connect to BIAS to set the output voltage to 5V.
7 OUT
Supply Input. OUT provides power to the internal circuitry when the output voltage of the converter
is set between 3V and 5V.
8 GND Ground
9 BIAS
Linear Regulator Output. BIAS powers up the internal circuitry. Bypass with a 1FF capacitor to ground.
10 BST
High-Side Driver Supply. Connect a 0.1FF capacitor between LX and BST for proper operation.
11 SUP
Voltage Supply Input. SUP powers up the internal linear regulator. Connect a minimum of 1FF
capacitor from SUP to GND close to the IC. Connect SUP to SUPSW.
12 LX Inductor Switching Node. Connect a Schottky diode between LX and GND.
13 SUPSW
Internal High-Side Switch Supply Input. SUPSW provides power to the internal switch. For most
applications, connect 4.7FF and 0.1FF capacitors between SUPSW and GND close to the IC. See
the Input Capacitor section for more details.
14 EN
Battery-Compatible Enable Input. Drive EN low to disable the device. Drive EN high to enable the
device.
15
RES
Open-Drain Active-Low Reset Output. RES asserts when V
OUT
is below the reset threshold set by
RESETI.
16 RESETI
Reset Threshold Level Input. Connect to a resistive divider to set the reset threshold for RES.
Connect to GND to enable the internal reset threshold.
— EP
Exposed Pad. Connect EP to a large-area contiguous copper ground plane for effective power
dissipation. Do not use as the only IC ground connection. EP must be connected to GND.