DS9535A Datasheet, PDF (3/18 Pages) Richtek Technology Corporation – High Efficiency Switching Mode Battery Charge

RT9535A
Functional Pin Description
Pin No.
Pin Name
Pin Function
1
EN
Enable Control Input (Active High). It must be connected to a logical voltage or
pulled up to VIN with a 100k resistor.
2
SS
Soft-Start Control Input. SS controls the soft-start time. Connect a capacitor
from SS pin to GND to set the soft-start time.
3
ISET
Charge Current Setting and System Loop Compensation Pin. Connect a
resistor from this pin to ground to set the charge current.
4
VC
Control Signal of the Inner Loop of the Current Mode PWM. A capacitor of at
least 0.1F with a serial resistor to GND filters out the current ripple.
5
NTC
Input for an external NTC thermistor for battery temperature monitoring.
6
VFB
Battery Voltage Feedback. Using an external resistor divider to set battery full
charge voltage.
To supply the current sense amplifier CA for very low dropout condition. It must
7
VHH
be connected as shown in the typical application circuit or connected to VIN if
VIN is always larger than BATT by at least 1.8V.
8
BATT
Battery Voltage Sensing Input. A 10F or larger X5R ceramic capacitor is
recommended for filtering charge current ripple and stability purpose.
9
SNSL
Negative Terminal for Sensing Charge Current.
10
SNSH
Positive Terminal for Sensing Charge Current.
11
PGND
12
SW
13
HSD
14
BOOT
15
VIN
16
V5V
17
(Exposed Pad)
GND
Power Ground.
Switch Node. This pin switches between ground and VIN with high dv/dt rates.
Care needs to be taken in the PCB layout to keep this node from coupling to
other sensitive nodes.
Drain of Internal High-Side Power N-MOSFET Switch. Connect a low ESR
capacitor of 10F or higher from this pin to ground for good bypass.
Bootstrap Supply for the High-Side Power Switch Gate Driver and Control
Circuitry. In normal operation, VBOOT ≈ VSW + 5V.
Input Power Supply. Connect a low ESR capacitor of 10F or higher from this
pin to ground for good bypass.
Output of Internal 5V LDO. Connect a 1F ceramic capacitor from this pin to
GND for stability.
Exposed Pad. Connect the exposed pad to PGND.
Copyright © 2016 Richtek Technology Corporation. All rights reserved.
DS9535A-04 February 2016
is a registered trademark of Richtek Technology Corporation.
www.richtek.com
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