Datasheet

ADP1046A Data Sheet
Rev. 0 | Page 10 of 88
PIN CONFIGURATION AND FUNCTION DESCRIPTIONS
1VS2
2AGND
3VS1
4CS2–
5CS2+
6ACSNS
7CS1
8PGND
24 SHAREi
23 SHAREo
22 PGOOD1
21 PGOOD2
20 FLAGIN
19 PSON
18 SDA
17 SCL
9SR1
10SR2
11OUTA
12OUTB
13OUTC
14OUTD
15OUTAUX
16GATE
32
VS3+
31
VS3–
30
RES
29
ADD
28
RTD
27
VDD
26
VCORE
25
DGND
ADP1046A
TOP VIEW
(Not to Scale)
NOTES
1. THE ADP1046A HAS AN EXPOSED THERMAL PAD ON THE UNDERSIDE OF
THE PACKAGE. FOR INCREASED RELIABILITY OF THE SOLDER JOINTS
AND MAXIMUM THERMAL CAPABILITY, IT IS RECOMMENDED THAT THE
PAD BE SOLDERED TO THE PCB AGND PLANE.
11012-003
Figure 3. Pin Configuration
Table 4. Pin Function Descriptions
Pin No. Mnemonic Description
1 VS2 Power Supply Output Voltage Sense Input. This signal is referenced to PGND and is the input to a low frequency
Σ-Δ ADC. Nominal voltage at this pin should be 1 V. The resistor divider on this input must have a tolerance
specification of 0.5% or better to allow for trimming.
2 AGND Analog Ground. This pin is the ground for the analog circuitry and the return for the VDD pin of the ADP1046A.
3 VS1 Local Output Voltage Sense Input. This signal is referenced to PGND. Nominal voltage at this pin should be 1 V.
The resistor divider on this input must have a tolerance specification of 0.5% or better to allow for trimming.
4 CS2− Inverting Differential Current Sense Input. Nominal voltage at this pin should be 1 V for best operation. When
using low-side current sensing, place a 5 kΩ resistor between the sense resistor and this pin. When using high-
side current sensing in a 12 V application, place a 5.5 kΩ resistor between the sense resistor and this pin. When
using high-side current sensing with a voltage other than 12 V, use the following formula to calculate the
resistor value: R = (V
OUT
− 1)/2 mA. A 0.1% resistor must be used to connect this circuit. If this pin is not used,
connect it to PGND and set CS2± to high-side current sense mode (set Bit 2 of Register 0x27). It is recommended
that a 500 pF to 1000 pF capacitor be connected either across the resistor or from this pin to AGND.
5 CS2+ Noninverting Differential Current Sense Input. Nominal voltage at this pin should be 1 V for best operation.
When using low-side current sensing, place a 5 kΩ resistor between the sense resistor and this pin. When using
high-side current sensing in a 12 V application, place a 5.5 kΩ resistor between the sense resistor and this pin.
When using high-side current sensing with a voltage other than 12 V, use the following formula to calculate the
resistor value: R = (V
OUT
− 1)/2 mA. A 0.1% resistor must be used to connect this circuit. If this pin is not used,
connect it to PGND and set CS2± to high-side current sense mode (set Bit 2 of Register 0x27). It is recommended
that a 500 pF to 1000 pF capacitor be connected either across the resistor or from this pin to AGND.
6
ACSNS
AC Sense Input. This input is connected upstream of the main output inductor through a resistor divider
network. The nominal voltage for this circuit is 0.45 V. This pin is also connected to the voltage feedforward
ADC (nominal voltage 1 V). This signal is referenced to PGND.
7 CS1 Primary Side Current Sense Input. This pin is connected to the primary side current sensing ADC and to the fast
OCP comparator. This signal is referenced to PGND. The resistors on this input must have a tolerance specification
of 0.5% or better to allow for trimming. If this pin is not used, connect it to PGND.
8 PGND Power Ground. This pin is the ground connection for the main power rail of the power supply and is the
reference for all voltage and current sensing other than CS2± and VS3±. Star connect to AGND.
9 SR1 Synchronous Rectifier Output. This PWM output connects to the input of a FET driver. This signal is referenced
to AGND. This pin can be disabled when not in use.
10 SR2 Synchronous Rectifier Output. This PWM output connects to the input of a FET driver. This signal is referenced
to AGND. This pin can be disabled when not in use.
11 OUTA PWM Output for Primary Side Switch. This signal is referenced to AGND. This pin can be disabled when not in use.
12 OUTB PWM Output for Primary Side Switch. This signal is referenced to AGND. This pin can be disabled when not in use.
13 OUTC PWM Output for Primary Side Switch. This signal is referenced to AGND. This pin can be disabled when not in use.