AAT4292

AAT4292 ANALOGICTECH

Document overview

• Manufacturer or author: Provided By www.digicamel.com(FREE DATASHEET DOWNLOAD SITE)
• PDF pages: 16

Technical content

Features

• V IN Range: 1.8V – 5.5V
• 7 Independent Output Channels
• 1.1 Ω RDS(ON) per Channel
• User Programmable AS 2Cwire Interface
• Low Quiescent Current ▪ 6.3 μA Operational ▪ 0.1 μA in shutdown
• -40°C to +85°C Temperature Range
• Available in SC70JW-10 Package

Applications

• Cell Phone Keypad, Backlight And Fashion Lighting Control
• I/O Expander
• Media Players
• Multiple Channel Low Power Switching
• Portable Electronic Devices Typical Application OUT1 GND AAT4292 OUT2 OUT3 OUT4 OUT5 OUT6 OUT7 EN/SET CIN VINInput Voltage Supply Control Logic Output 1 Output 2 Output 3 Output 4 Output 5 Output 6 Output 7 1μF

Seven Channel High-Side I/O ExpanderSmartSwitch TM PRODUCT DATASHEET AAT4292 Seven Channel High-Side I/O ExpanderSmartSwitch TM PRODUCT DATASHEET Pin Descriptions Symbol Pin # Function OUT4 1 P-channel MOSFET drain; Channel 4 output pin. OUT5 2 P-channel MOSFET drain; Channel 5 output pin. OUT6 3 P-channel MOSFET drain; Channel 6 output pin. OUT7 4 P-channel MOSFET drain; Channel 7 output pin. GND 5 Ground connection. EN/SET 6 Input control pin using AS 2Cwire serial interface. The device records rising edges of the clock, and decodes them into 128 states controlling the ON/OFF states of the outputs. See Table 1 and Table 2 for output settings. In addition, a logic low forces the device into shutdown mode, reducing the supply cur- rent to less than 1μA. This pin should not be left fl oating. OUT1 7 P-channel MOSFET drain; Channel 1 output pin. OUT2 8 P-channel MOSFET drain, Channel 2 output pin. OUT3 9 P-channel MOSFET drain, Channel 3 output pin. VIN 10 Input supply voltage. VIN is connected to the P-channel MOSFET common sources. Connect a 1μF ce- ramic capacitor from VIN to GND. Pin Configuration SC70JW-10 (Top View) OUT4 OUT5 OUT6 OUT7 GND VIN OUT3 OUT2 OUT1 EN/SET

Seven Channel High-Side I/O ExpanderSmartSwitch TM PRODUCT DATASHEET AAT4292 Seven Channel High-Side I/O ExpanderSmartSwitch TM PRODUCT DATASHEET Absolute Maximum Ratings1 Symbol Description Value Units VIN VIN to GND -0.3 to 6.0 V VOUT OUT to GND -0.3 to V IN + 0.3 V VEN/SET EN/SET to GND -0.3 to 6.0 V IMAX Maximum Continuous Switch Current 250 mA TJ Operating Junction Temperature Range -40 to 150 °C VESD ESD Rating – HBM 2 4000 V Thermal Information Symbol Description Value Units ΘJA Thermal Resistance3 225 °C/W PD Maximum Power Dissipation 4 (TA = 25°C) 440 mW 1. Stresses above those listed in Absolute Maximum Ratings may cause permanent damage to the device. Functional operation at co nditions other than the operating conditions specified is not implied. Only one Absolute Maximum rating should be applied at any one time. 2. Human body model is a 100pF capacitor discharged through a 1.5k Ω resistor to each pin. 3. Mounted on a FR4 board. 4. Derate 4.4mW/°C above 25°C.

Seven Channel High-Side I/O ExpanderSmartSwitch TM PRODUCT DATASHEET AAT4292 Seven Channel High-Side I/O ExpanderSmartSwitch TM PRODUCT DATASHEET Electrical Characteristics1 VIN = 5.0V, TA = -40°C to 85°C unless otherwise noted. Typical values are T A = 25°C. Symbol Description Conditions Min Typ Max Units Power Supply and MOSFETs VIN Operation Voltage 1.8 5.5 V IQ Quiescent Current EN/SET = VIN = 5V, IOUTn = 0, All Switches ON 6.3 10 μA ISD(OFF) Shutdown Current EN/SET = GND, V IN = 5V, OUTn = 0 0.1 1.0 μA RDS(ON) P-Channel High-Side MOSFET On-State Resistance VIN = 5.0V, IOUTn = 100mA, TA = 25oC 1.1 1.7 ΩVIN = 4.2V, IOUTn = 100mA, TA = 25oC 1.2 1.8 VIN = 3.0V, IOUTn = 100mA, TA = 25oC 1.5 2.2 VIN = 1.8V, IOUTn = 100mA, TA = 25oC 2.5 3.8 TCRDS On-State Resistance Temperature Coeffi cient 2800 ppm/ °C Switch Timing tD(ON) Output Turn-On Delay Time2 VIN = 5V, RLOAD = 500Ω, COUT = 100nF 40 nstR Turn-On Rise Time VIN = 5V, RLOAD = 500Ω, COUT = 100nF 270 tD(OFF) Output Turn-Off Delay Time3 VIN = 5V, RLOAD = 500Ω 40 Control Logic (EN/SET) VEN(L) Enable Threshold Low V IN = 1.8V 0.4 V VEN(H) Enable Threshold High V IN = 5.5V 1.6 V tLO EN/SET Low Time V EN/SET < 0.4V 100 ns tHI Minimum EN/SET High Time VIN ≤ 2.5V 500 nsVIN > 2.5V 250 tOFF EN/SET Off Timeout 1.3 4.0 μs tLAT EN/SET Latch Timeout 1.15 4.0 μs ISINK EN/SET Input Leakage Current V EN/SET = 5.5V 0.01 1.0 μA 1. The AAT4292 is guaranteed to meet performance specification over the –40°C to +85°C operating temperature range, and is assu red by design, characterization and correla- tion with statistical process controls. 2. tD(ON) is the time after latch timeout to 90% of the output voltage. 3. tD(OFF) is the time after off timeout to 10% of the output voltage.

Seven Channel High-Side I/O ExpanderSmartSwitch TM PRODUCT DATASHEET AAT4292 Seven Channel High-Side I/O ExpanderSmartSwitch TM PRODUCT DATASHEET Typical Characteristics Unless otherwise noted, VIN = 5.0V, CIN = 1μF, COUTn = 0.1μF, TA = 25°C. Quiescent Current vs. Input Voltage Input Voltage (V) Quiescent Current (µA) Quiescent Current vs. Temperature Temperature (°C) Quiescent Current (µA) -40 -15 10 35 60 85 VIN = 5.0V VIN = 3.3V VEN(H) and VEN(L) vs. Input Voltage Input Voltage (V) VEN(H) and VEN(L) (V) 0.5 0.6 0.7 0.8 0.9 1.1 1.2 1.3 1.4 1.5 VEN(H) VEN(L) RDS(ON) vs. Input Voltage (IOUT1-7 = 100mA) Input Voltage (V) RDS(ON) (ΩΩ) 0.7 0.9 1.1 1.3 1.5 1.7 1.9 2.1 2.3 2.5 2.7 RDS1 RDS2 RDS3 RDS4 RDS5 RDS6 RDS7 RDS(ON) vs. Temperature (VIN = 5.0V; IOUT1-7 = 100mA) Temperature (°C) RDS(ON) (ΩΩ) -40 -15 10 35 60 85 0.5 0.6 0.7 0.8 0.9 1.1 1.2 1.3 1.4 RDS1 RDS2 RDS3 RDS4 RDS5 RDS6 RDS7 RDS(ON) vs. Temperature (VIN = 5.0V; IOUT1-7 = 10mA) Temperature (°C) RDS(ON) (ΩΩ) -40 -15 10 35 60 85 0.5 0.6 0.7 0.8 0.9 1.1 1.2 1.3 1.4 RDS1 RDS2 RDS3 RDS4 RDS5 RDS6 RDS7

Seven Channel High-Side I/O ExpanderSmartSwitch TM PRODUCT DATASHEET AAT4292 Seven Channel High-Side I/O ExpanderSmartSwitch TM PRODUCT DATASHEET Typical Characteristics Unless otherwise noted, VIN = 5.0V, CIN = 1μF, COUTn = 0.1μF, TA = 25°C. EN/SET Latch Timeout vs. Temperature Temperature (°C) Latch Timeout, tLAT (µs) -40 -15 10 35 60 85 1.1 1.2 1.3 1.4 VIN = 5.0V VIN = 3.3V EN/SET Off Timeout vs. Temperature Temperature (°C) Off Timeout, tOFF (µs) -40 -15 10 35 60 85 1.1 1.2 1.3 1.4 1.5 VIN = 5.0V VIN = 3.3V EN/SET Timeout vs. Input Voltage Input Voltage (V) Timeout (µs) 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 Off Timeout Latch Timeout Turn-On Characteristic (VIN = 5V; RL2 = RL6 = RL7 = 50ΩΩ; CO2 = CO6 = CO7 = 0.1µF) Time (2µs/div) VOUT2 (5V/div) VOUT7 (5V/div) VOUT6 (5V/div) EN/SET (5V/div) Turn-On Characteristic (VIN = 5V; RL2 = RL6 = RL7 = 50ΩΩ; CO2 = CO6 = CO7 = 0.1µF) Time (10µs/div) VOUT2 (5V/div) VOUT7 (5V/div) VOUT6 (5V/div) EN/SET (5V/div) Turn-On Characteristic (VIN = 5V; RL2 = RL6 = RL7 = 50ΩΩ; CO2 = CO6 = CO7 = 0.1µF) Time (10µs/div) VOUT2 (5V/div) VOUT7 (5V/div) VOUT6 (5V/div) EN/SET (5V/div)

Seven Channel High-Side I/O ExpanderSmartSwitch TM PRODUCT DATASHEET AAT4292 Seven Channel High-Side I/O ExpanderSmartSwitch TM PRODUCT DATASHEET Typical Characteristics Unless otherwise noted, VIN = 5.0V, CIN = 1μF, COUTn = 0.1μF, TA = 25°C. Turn-On Characteristic (VIN = 5V; RL2 = RL6 = RL7 = 50ΩΩ; CO2 = CO6 = CO7 = 0.1µF) Time (10µs/div) VOUT2 (5V/div) VOUT7 (5V/div) VOUT6 (5V/div) EN/SET (5V/div) Turn-On Characteristic (VIN = 5V; RL2 = RL6 = RL7 = 50ΩΩ; CO2 = CO6 = CO7 = 0.1µF) Time (10µs/div) VOUT2 (5V/div) VOUT7 (5V/div) VOUT6 (5V/div) EN/SET (5V/div) Transition of Outputs (VIN = 5V; RL2 = RL6 = RL7 = 50ΩΩ; CO2 = CO6 = CO7 = 0.1µF) Time (10µs/div) VOUT2 (5V/div) VOUT7 (5V/div) VOUT6 (5V/div) EN/SET (5V/div) Turn-Off Characteristic (VIN = 5V; RL2 = RL6 = RL7 = 50ΩΩ; CO2 = CO6 = CO7 = 0.1µF) Time (10µs/div) VOUT2 (5V/div) VOUT7 (5V/div) VOUT6 (5V/div) EN/SET (5V/div)

Seven Channel High-Side I/O ExpanderSmartSwitch TM PRODUCT DATASHEET AAT4292 Seven Channel High-Side I/O ExpanderSmartSwitch TM PRODUCT DATASHEET Functional Description The AAT4292 consists of seven P-channel MOSFET power switches designed for I/O expansion applications. The device operates with input voltages ranging from 1.8V to 5.5V which, along with its extremely low operating cur- rent, makes it ideal for battery-powered applications. In cases where the input voltage drops below 1.8V, the AAT4292 MOSFETs are protected from entering the linear region of operation by automatically shutting down. In addition, the TTL-compatible EN/SET pin makes the AAT4292 an ideal level-shifted load switch. An optional slew rate controlling feature eliminates inrush current when a MOSFET is turned on, allowing the AAT4292 to be implemented with a small input capacitor or no capacitor at all, while maintaining isolation between channels. During slewing, the current ramps linearly until it reaches the level required for the output load condition. The proprietary control method works by careful control and monitoring of the MOSFET gate volt- Functional Block Diagram AS2Cwire Interface ROM Logic Control and Level ShiftUVLO GND OUT7 OUT6 OUT5 OUT4 OUT3 OUT2 OUT1VIN EN/SET

Seven Channel High-Side I/O ExpanderSmartSwitch TM PRODUCT DATASHEET age. When the device is switched ON, the gate voltage is quickly increased to the threshold level of the MOSFET. Once at this level, the current begins to slew as the gate voltage is slowly increased until the MOSFET becomes fully enhanced. Once it has reached this point, the gate is quickly increased to the full input voltage and R DS(ON) is minimized. The ON/OFF states of the seven MOSFET switches are controlled by the EN/SET serial clock input. An internal control counter is clocked on the rising edges of the EN/ SET pin and is decoded into 128 possible states of the MOSFET (see Table 1 and Table 2). The counter can be clocked at speeds up to 1MHz, but the count value is not latched until clocking has stopped and the EN/SET pin has remained high for the t LAT timeout (approximate 1.15μs typical). The first rising edge of EN/SET enables the AAT4292 and is counted as the first clock. There are four address switch bank in AAT4292, which is selected by the corresponding rising edges 33 to 36, after remaining the EN/SET high for the t LAT timeout, then the clock number is latched and the relevant address switch bank (0 to 3) is asserted. Next, the cor- responding rising edges of Data from 1 to 32 can be serial submitted, and closed by the EN/SET remaining high for t LAT timeout. After the timeout t LAT, the outputs status is updated accordingly. The AAT4292 is disabled after the EN/SET pin has tran- sitioned and remained in a logic low for tOFF timeout, and the quiescent current drops to 0.1μA typically. AS2Cwire Serial Interface The ON/OFF states of the seven output channels are con- trolled by the EN/SET serial data input. An internal con- trol counter is clocked on the rising edge of the EN/SET pin and is decoded into one of 128 possible states using a short address and data word (see Tables 1 and 2). AS 2Cwire relies on the number of rising edges of the EN/ SET pin to address and load the registers, as illustrated in Figure 1. AS 2Cwire latches data (1 to 32 edges) or address (33 to 36 edges) after the EN/SET pin has been held high for time t LAT. The interface records rising edges of the EN/SET pin and decodes them into one of four addresses corresponding to the address table (Table 1), or 1 of 32 data settings corresponding to the switch code table (Table 2). The combined address and data is used to decode one of 128 possible switch states. Address and Data are differentiated by the number of rising edges on the EN/SET pin. 1 to 32 rising edges signifies Data, and 33 to 36 rising edges signifies Address. The counter can be clocked at speeds up to 1MHz, such that intermediate states are not visible. The first rising edge of EN/SET enables the IC and turns the switches OUT3-OUT7 on. Once the final clock cycle is received, the EN/SET pin is held high to maintain the device setting. The device is disabled after the EN/SET pin transitions to a logic low state for t OFF timeout (approximate 1.3μs typical). Address Code Address Switch Bank Code EN/SET Rising Edges 03 3 13 4 23 5 33 6 Table 1: AS2Cwire Address Table.

Seven Channel High-Side I/O ExpanderSmartSwitch TM PRODUCT DATASHEET Data Code Address Data OUT1 OUT2 OUT3 OUT4 OUT5 OUT6 OUT7 Address Data OUT1 OUT2 OUT3 OUT4 OUT5 OUT6 OUT7 1o no no no no no no n 1 off on on on on on on 2 on on on on on on off 2 off on on on on on off 3 on on on on on off on 3 off on on on on off on 4 on on on on on off off 4 off on on on on off off 5 on on on on off on on 5 off on on on off on on 6 on on on on off on off 6 off on on on off on off 7 on on on on off off on 7 off on on on off off on 8 on on on on off off off 8 off on on on off off off 9 on on on off on on on 9 off on on off on on on 10 on on on off on on off 10 off on on off on on off 11 on on on off on off on 11 off on on off on off on 12 on on on off on off off 12 off on on off on off off 13 on on on off off on on 13 off on on off off on on 14 on on on off off on off 14 off on on off off on off 15 on on on off off off on 15 off on on off off off on 16 on on on off off off off 16 off on on off off off off 17 on on off on on on on 17 off on off on on on on 18 on on off on on on off 18 off on off on on on off 19 on on off on on off on 19 off on off on on off on 20 on on off on on off off 20 off on off on on off off 21 on on off on off on on 21 off on off on off on on 22 on on off on off on off 22 off on off on off on off 23 on on off on off off on 23 off on off on off off on 24 on on off on off off off 24 off on off on off off off 25 on on off off on on on 25 off on off off on on on 26 on on off off on on off 26 off on off off on on off 27 on on off off on off on 27 off on off off on off on 28 on on off off on off off 28 off on off off on off off 29 on on off off off on on 29 off on off off off on on 30 on on off off off on off 30 off on off off off on off 31 on on off off off off on 31 off on off off off off on 32 on on off off off off off 32 off on off off off off off Address Data OUT1 OUT2 OUT3 OUT4 OUT5 OUT6 OUT7 Address Data OUT1 OUT2 OUT3 OUT4 OUT5 OUT6 OUT7 1 on off on on on on on 1 off off on on on on on 2 on off on on on on off 2 off off on on on on off 3 on off on on on off on 3 off off on on on off on 4 on off on on on off off 4 off off on on on off off 5 on off on on off on on 5 off off on on off on on 6 on off on on off on off 6 off off on on off on off 7 on off on on off off on 7 off off on on off off on 8 on off on on off off off 8 off off on on off off off 9 on off on off on on on 9 off off on off on on on 10 on off on off on on off 10 off off on off on on off 11 on off on off on off on 11 off off on off on off on 12 on off on off on off off 12 off off on off on off off 13 on off on off off on on 13 off off on off off on on 14 on off on off off on off 14 off off on off off on off 15 on off on off off off on 15 off off on off off off on 16 on off on off off off off 16 off off on off off off off 17 on off off on on on on 17 off off off on on on on 18 on off off on on on off 18 off off off on on on off 19 on off off on on off on 19 off off off on on off on 20 on off off on on off off 20 off off off on on off off 21 on off off on off on on 21 off off off on off on on 22 on off off on off on off 22 off off off on off on off 23 on off off on off off on 23 off off off on off off on 24 on off off on off off off 24 off off off on off off off 25 on off off off on on on 25 off off off off on on on 26 on off off off on on off 26 off off off off on on off 27 on off off off on off on 27 off off off off on off on 28 on off off off on off off 28 off off off off on off off 29 on off off off off on on 29 off off off off off on on 30 on off off off off on off 30 off off off off off on off 31 on off off off off off on 31 off off off off off off on 32 on off off off off off off 32 off off off off off off off Table 2: AS2Cwire Data Code Table.

Seven Channel High-Side I/O ExpanderSmartSwitch TM PRODUCT DATASHEET

Application Information

The AAT4292 is designed to deliver continuous output load currents. Due to its high integration, care must be taken in designing for higher load conditions. If greater loads are required, outputs can be tied together to deliver higher power to a given load. For the thermal calculation, assuming that the total cur- rent capability of the seven channels is I TOTAL, each chan- nel has the same current which is IOUT = ITOTAL 7 , then PTOTAL = 7IOUT 2RDS(ON) = 7 RDS(ON) = PD - PDERATE(TA - 25) ITOTAL Where: PD = 440mW when TA = 25°C PDERATE = 4.4mW/°C RDS(ON) = 1.7Ω (maximum) when VIN = 5.0V For example, at 25oC ambient, the AAT4292 power capa- bility is PTOTAL = 440mW, then ITOTAL ≅ 1.35A at VIN = 5.0V. The current capability for each channel is IOUT = 192mA. At 85oC ambient, the AAT4292 power capability is P TOTAL = 440 - (85 - 25)4.4 = 176mW, then ITOTAL ≅ 0.85A at VIN = 5.0V. The current capability for each channel is IOUT = 121mA. Output Sequencing If output sequencing is not necessary, then a pulse burst of 33 address clocks followed by 1 data clock will switch on all of the outputs simultaneously. Alternately, the OUT3 to OUT7 will be switched on simultaneously on the first rising edge of the EN/SET pin after the t LAT timeout. Output sequencing is accomplished via a series of pulses on the EN/SET pin. Each time a new pulse burst is asserted on EN/SET, the AAT4292 internal clock counter starts to count and sends the counted clock number to the register. After the t LAT timeout, the internal clock counter is reset and waits for the next pulse burst. For example, to sequence the outputs in order from OUT1 to OUT7, seven clock bursts are input on the EN/SET pin. From Table 1 and Table 2, the first bust of 34 address clocks followed by 32 data clocks turns on OUT1. The next burst of 33 address clocks followed by 32 data clocks will add OUT2. Then the burst of 33 address clocks followed by 16 data clocks will add OUT3; the burst of 33 address clocks followed by 8 data clocks will add OUT4; the burst of 33 address clocks followed by 4 data clocks will add OUT5; the burst of 33 address clocks followed by 2 data clocks will add OUT6; the burst of 33 address clocks followed by 1 data clock will add OUT7. Likewise, the outputs can be turned on/off in any order by adding the corresponding clock bursts. Input Capacitor Normally, the input capacitor value could be ten times that of the total load capacitors. If the device outputs OUT1 to OUT7 have capacitor loads, depending on the load capacitor value, it is recommended that a 1 μF to 10μF 0603 or 0805 ceramic capacitor be placed as close as possible between VIN and GND. For example, if the capacitor load at each output is 0.1 μF, the Murata GRM21BR61C106K ceramic capacitor (10 μF/16V/0805/ X5R) or a similar capacitor could be used. This helps to provide a low impendence loop to charge the load capac- itors during the MOSFET switches' turn-on transient and keep the V IN voltage stable.

Seven Channel High-Side I/O ExpanderSmartSwitch TM PRODUCT DATASHEET AAT4292 Seven Channel High-Side I/O ExpanderSmartSwitch TM PRODUCT DATASHEET Evaluation Board Layout Figure 5: AAT4292 Evaluation Board Layout Figure 6: AAT4292 Evaluation Board Layout Top Layer (not to scale). Bottom Layer (not to scale).

Seven Channel High-Side I/O ExpanderSmartSwitch TM PRODUCT DATASHEET AAT4292 Seven Channel High-Side I/O ExpanderSmartSwitch TM PRODUCT DATASHEET

Ordering Information

Package Marking 1 Part Number (Tape & Reel)2 SC70JW-10 4WXYY AAT4292IJQ-T1 All AnalogicTech products are offered in Pb-free packaging. The term “Pb-free” means semiconductor products that are in compliance with current RoHS standards, including the requirement that lead not exceed 0.1% by weight in homogeneous materials. For more information, please visit our website at http://www.analogictech.com/about/quality.aspx. Packaging Information SC70JW-10 0.45 ± 0.10 0.05 ± 0.05 2.10 ± 0.30 4° ± 4° 0.15 ± 0.05 2.00 ± 0.20 7° ± 3° 0.85 ± 0.15

1.10 MAX

0.100 0.225 ± 0.075 1.75 ± 0.10 2.20 ± 0.20

0.40 BSC

All dimensions in millimeters. 1. XYY= assembly and date code. 2. Sample stock is generally held on part numbers listed in BOLD.

Seven Channel High-Side I/O ExpanderSmartSwitch TM PRODUCT DATASHEET AAT4292 Seven Channel High-Side I/O ExpanderSmartSwitch TM PRODUCT DATASHEET Advanced Analogic Technologies, Inc.

3230 Scott Boulevard, Santa Clara, CA 95054

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