23A256/23K256 256K SPI Bus Low-Power Serial SRAM Device Selection Table Part Number VCC Range Page Size Temp. Ranges Packages 23K256 2.7-3.6V 32 Byte I P, SN, ST 23A256 1.7-1.95V 32 Byte I P, SN, ST Features: Description: Max. Clock 20 MHz The Microchip Technology Inc. 23X256 are 256 Kbit Serial SRAM devices. The memory is accessed via a Low-Power CMOS Technology: simple Serial Peripheral Interface (SPI) compatible - Read Current: 3 mA at 1 MHz serial bus. The bus signals required are a clock input - Standby Current: 4 A Max. at 3.6V (SCK) plus separate data in (SI) and data out (SO) 32,768 x 8-bit Organization lines. Access to the device is controlled through a Chip 32-Byte Page Select (CS) input. HOLD pin Communication to the device can be paused via the Flexible Operating modes: hold pin (HOLD). While the device is paused, transitions on its inputs will be ignored, with the - Byte read and write exception of Chip Select, allowing the host to service - Page mode (32 Byte Page) higher priority interrupts. - Sequential mode The 23X256 is available in standard packages Sequential Read/Write including 8-lead PDIP and SOIC, and advanced High Reliability packaging including 8-lead TSSOP. Temperature Ranges Supported: - Industrial (I): -40Cto +85C Package Types (not to scale) Pb-Free and RoHS Compliant, Halogen Free Pin Function Table Name Function CS Chip Select Input PDIP/SOIC/TSSOP SO Serial Data Output (P, SN, ST) VSS Ground SI Serial Data Input CS 1 8 VCC SCK Serial Clock Input SO 2 7 HOLD Hold Input HOLD NC 3 6 SCK VCC Supply Voltage VSS 4 5 SI 2009 Microchip Technology Inc. Preliminary DS22100C-page 123A256/23K256 1.0 ELECTRICAL CHARACTERISTICS () Absolute Maximum Ratings VCC.............................................................................................................................................................................4.5V All inputs and outputs w.r.t. VSS ......................................................................................................... -0.3V to VCC +0.3V Storage temperature .................................................................................................................................-40C to 125C Ambient temperature under bias.................................................................................................................-40C to 85C ESD protection on all pins...........................................................................................................................................2kV NOTICE: Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating only and functional operation of the device at those or any other conditions above those indicated in the operational listings of this specification is not implied. Exposure to maximum rating conditions for an extended period of time may affect device reliability. TABLE 1-1: DC CHARACTERISTICS Industrial (I): TA = -40C to +85C DC CHARACTERISTICS Param. (1) Sym. Characteristic Min. Typ Max. Units Test Conditions No. D001 VCC Supply voltage 1.7 1.95 V 23A256 D001 VCC Supply voltage 2.7 3.6 V 23K256 D002 VIH High-level input .7 VCC VCC V voltage +0.3 D003 VIL Low-level input -0.3 0.2xVCC V voltage D004 VOL Low-level output 0.2 VIOL = 1 mA voltage D005 VOH High-level output VCC -0.5 V IOH = -400 A voltage D006 ILI Input leakage 0.5 ACS = VCC, VIN = VSS OR VCC current D007 ILO Output leakage 0.5 ACS = VCC, VOUT = VSS OR VCC current D008 ICC Read CLK = 1 MHz SO = O 3 mA F 6 mA FCLK = 10 MHz SO = O Operating current 10 mA FCLK = 20 MHz SO = O D009 ICCS 200 500 nA CS = VCC = 1.8V, Inputs tied to VCC Standby current or VSS 1 4 A CS = VCC = 3.0V, Inputs tied to VCC or VSS D010 CINT Input capacitance 7 pF VCC = 0V, f = 1 MHz, Ta = 25C (Note 1) D011 VDR RAM data retention 1.2 V (2) voltage Note 1: This parameter is periodically sampled and not 100% tested. Typical measurements taken at room temperature (25C). 2: This is the limit to which VDD can be lowered without losing RAM data. This parameter is periodically sampled and not 100% tested. DS22100C-page 2 Preliminary 2009 Microchip Technology Inc.